JP2008267358A - Centrifugal impeller and centrifugal pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a centrifugal impeller and a centrifugal pump used as rotating in regular and reverse directions, which radially pushes out liquid when rotating in one direction and does not substantially push out liquid when rotating in another direction. <P>SOLUTION: In the centrifugal impeller 28, a main wing 28b for scraping out the liquid is provided with a wing inner diameter part 28b1 for forming a liquid push out part for pushing out the liquid to an outer diameter side during regular rotation and a wing outer diameter part 28b2 for forming a liquid suppressing part for suppressing a flow of the liquid toward the outer diameter side during reverse rotation. This centrifugal impeller can push out the liquid toward the outer diameter side during the regular rotation and can refrain from pushing out the liquid during the reverse rotation. The pump provided with this centrifugal impeller can switch a discharge method whether delivering the liquid taken in a pump chamber from a delivering port of the pump chamber or not depending on the rotation direction of the impeller. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a centrifugal impeller and a centrifugal pump that are used in a forward and reverse rotation in a centrifugal pump.

  A centrifugal pump includes a reversible pump that can discharge water sucked into a pump chamber from a water suction port from one of two discharge ports in accordance with forward or reverse rotation of an impeller.

  Such a reversible pump is suitable for a liquid circulation device (Patent Document 1) having a structure for circulating a liquid using a pump such as a washing machine or a dishwasher, and circulates water taken into the device. The circulation function and the discharge function for discharging the water can be realized with one pump (Patent Document 2). This reversible pump is equipped with two centrifugal impellers with different liquid pushing forces to push the liquid to the outer diameter side depending on the direction of rotation in one motor that rotates forward and reverse. Liquid is discharged from the reversing outlet of the pump chamber with the forward impeller having a large pushing force, and when the motor is reversed, the liquid is discharged from the reversing outlet of the pump chamber having the reversing impeller having a large pushing force at the time of reversing. To do. For this reason, connecting the normal discharge outlet to the pipe corresponding to the circulation function of the equipment equipped with the pump and connecting the reverse discharge outlet to the pipe corresponding to the discharge function of the equipment, both functions are unified. Can be run with two pumps.

JP 2002-85894 A Japanese Utility Model Publication No. 3-46709

  By the way, in the reversible pump, since the two impellers rotate regardless of the motor rotation, the liquid is pushed out even when the reversing impeller rotates forward, and the liquid is pushed out also when the forward impeller reverses. End up. Therefore, at the time of normal rotation of the motor, a large amount of liquid is discharged from the normal rotation discharge port, but a small amount of liquid may be leaked from the reverse discharge port. Similarly, even when the motor is reversed, a large amount of liquid is discharged from the reversing discharge port, but a small amount of liquid may be leaked from the normal rotation discharging port. Therefore, in the conventional reversible pump, since the impeller has originally pushed out the liquid when it is not necessary to extrude the liquid, the pump efficiency is not good. In addition, since the liquid leaks from the discharge port that does not need to be discharged, a structure such as a sealing valve that prevents the liquid flow from the pump itself or the piping on the equipment side to which the discharge port is connected is necessary. Therefore, the pump or the device on which the pump is mounted becomes a complicated structure and increases in size.

  The present invention has been made in view of the above problems, and the object of the present invention is to use the liquid in a forward and reverse rotation that extrudes radially outward when rotating in one direction and does not substantially extrude when rotated in the other direction. A centrifugal impeller and a centrifugal pump.

  The centrifugal impeller of the present invention has a configuration in which the main wing is provided with a liquid extruding portion that pushes the liquid to the outer diameter side during normal rotation and a liquid suppression portion that suppresses the flow of the liquid toward the outer diameter side during reversal. Thus, the centrifugal impeller can extrude the liquid to the outer diameter side during normal rotation and not extrude the liquid during inversion. A pump equipped with this centrifugal impeller can switch whether or not the liquid can be discharged from the discharge port of the liquid taken into the pump chamber according to the rotation direction of the impeller.

  More specifically, in the centrifugal impeller according to claim 1, in the centrifugal impeller used by rotating forward and reverse in the centrifugal pump, a disk portion provided coaxially with the rotation shaft, and a plane of the disk portion. A plurality of main wings provided radially about the rotation axis, and the main wing includes a liquid extruding portion that pushes liquid to the outer diameter side when the impeller rotates forward, and when the impeller is reversed. And a first liquid suppression unit that suppresses the flow of liquid toward the outer diameter side.

  The centrifugal impeller according to claim 2, wherein the main wing has a blade inner diameter portion that approaches the rotation shaft side toward a normal rotation direction when the impeller rotates in the forward direction, and the liquid pushing portion has the blade inner diameter. It is formed in the outer surface of a part.

  In the centrifugal impeller according to claim 3, the main wing has a blade outer diameter portion extending in a circumferential direction around the rotation axis from an outer diameter end of the blade inner diameter portion, and the first liquid suppressing portion is It is formed in the inner surface of the said blade outer diameter part, It is characterized by the above-mentioned.

  In the centrifugal impeller according to claim 4, the inner diameter end portion of the main wing and the outer diameter end portion of another main wing on the outer diameter side of the main wing are substantially on a straight line in the radial direction centering on the rotation axis. It is characterized by being located.

  The centrifugal impeller according to claim 5, wherein the disk portion is provided with a second liquid suppressing portion that suppresses a flow of liquid toward the outer diameter side of the main wing when the impeller is reversed. To do.

  The centrifugal impeller according to claim 6 is characterized in that the second liquid suppressing portion is a surface formed in a circumferential direction around the rotation axis.

  In the centrifugal impeller according to claim 7, the forward end of the impeller in the forward direction of the impeller in the second liquid suppression portion and the outer diameter end portion of the main wing adjacent to the inner diameter side of the second liquid suppression portion, It is substantially located on a straight line in the radial direction around the rotation axis.

  The centrifugal impeller according to claim 8, wherein an end portion of the second liquid suppression portion on the rear side in the forward rotation direction of the impeller is an outer diameter end of the outer surface of the main wing adjacent to the inner diameter side of the second liquid suppression portion. It is located in the range which does not exceed the tangent line prescribed | regulated when planarly viewed.

  The centrifugal impeller according to claim 9, wherein an end of the second liquid suppressing portion in the forward direction of the impeller is an inner diameter of an outer surface of the blade outer diameter portion adjacent to an inner diameter side of the second liquid suppressing portion. The end is located in a range not exceeding a tangent line defined when viewed in plan.

  A centrifugal pump according to claim 10 houses the centrifugal impeller according to any one of claims 1 to 9, a reversible motor for rotating or reversing the centrifugal impeller, and the centrifugal impeller. A pump chamber, a water suction port for guiding the liquid outside the pump chamber to the pump chamber, and a discharge port for guiding the liquid taken into the pump chamber to the outside of the pump chamber, To do.

  In the centrifugal pump according to claim 11, the first centrifugal impeller according to any one of claims 1 to 9, the second centrifugal impeller according to any one of claims 1 to 9, and the first A reversible motor in which the centrifugal impeller and the second centrifugal impeller are arranged in directions opposite or opposite to each other, and a pump that houses the first centrifugal impeller and the second centrifugal impeller A first suction guide for guiding the liquid outside the pump chamber to the pump chamber and the liquid taken into the pump chamber to the outside of the pump chamber by the first centrifugal impeller. A discharge port and a second discharge port for guiding the liquid taken into the pump chamber to the outside of the pump chamber by the second centrifugal impeller.

  In the centrifugal impeller of the present invention, the pushing force for pushing the liquid to the outer diameter side when rotating in one direction of normal rotation or reversal can be made extremely smaller than the pushing force when rotating in the other direction. In the centrifugal pump according to the present invention, the pump characteristic can be made extremely smaller than the pump characteristic when the centrifugal impeller rotating in the forward / reverse direction rotates in any one direction.

  An embodiment of a centrifugal impeller and a centrifugal pump according to the present invention will be described with reference to FIGS. 1 to 6 using a pump used in a washing machine.

[Washing machine equipped with pump of the present invention]
A washing machine 50 shown in FIG. 1 is provided with a washing tub 52 having a large number of small holes for storing laundry in a washing machine main body 51, and an outer tub 53 for storing the washing tub 52 inside and storing water. ing. The water stored in the outer tub 53 is also stored in the washing tub 52 through a large number of small holes in the washing tub 52. The outer tub 53 and the washing tub 52 are supported by the washing machine body 51 via a vibration isolation mechanism (not shown). The washing tub 52 is rotatably supported in the outer tub 53 by a rotating shaft mechanism 54 fixed at the center. The rotating shaft mechanism 54 is connected to the motor (M). The outer tub 53 is provided with a water supply pipe 56 provided with a water supply valve 55 for supplying tap water. In addition, an operation panel 57 containing a control circuit centering on a microcomputer for controlling the operation of each washing process is provided on the exterior front surface of the washing machine main body 51.

  The washing machine 50 has a function of supplying tap water to the washing tub 52, and circulates water stored in the washing tub 52 and the outer tub 53 during the washing in the washing machine main body 51, thereby dissolving the detergent into the laundry. A circulation function for removing foreign matters such as adhered dirt and lint, and a discharge function for forcibly discharging the water in the washing tub 52 and the outer tub 53 to the outside of the machine are provided. In this case, the circulation function corresponds to a washing process and a rinsing process in the washing machine, and the discharge function corresponds to a draining process and a dehydrating process. A pump 10 according to the present invention, which will be described later, is applied as a circulation / discharge pump that performs the circulation function and the discharge function, and is provided on the bottom rear surface side of the outer tub 53 in the washing machine body 51.

  In the circulation function of the washing machine 50, as indicated by an arrow r1 in FIG. 1, the water in the outer tub 53 including the washing tub 52 is converted into the first circulation pipe 58 and the second circulation pipe 59 by the circulation function of the pump 10. Then, it is supplied again to the outer tank 53 (corresponding to the first flow path). In the discharge function of the washing machine 50, the water in the outer tub 53 including the washing tub 52 is passed through the first circulation pipe 58 and the discharge pipe 60 by the discharge function of the pump 10, as indicated by an arrow r2 in FIG. And discharged to the outside of the machine (corresponding to the second flow path).

[Structure and operation of motor section]
The pump 10 shown in FIG. 2 is a centrifugal type, and has a circulation function for circulating water as in a washing and rinsing process in a washing machine, and a discharge for forcibly discharging water in the apparatus as in a drainage and dehydration process. Used to perform functions. In this pump 10, the motor unit 20 and the pump chamber 30 are integrated, and one pump chamber is provided with one water inlet and two outlets, and the rotation direction of the motor unit 20 is switched. Thus, the operation is performed in two discharge modes including a first discharge mode in which water is discharged from one discharge port and a second discharge mode in which water is discharged from the other discharge port. Further, the pump 10 is provided with a centrifugal impeller of the present invention, which will be described later, in one pump chamber 20 and is rotated forward and backward by the motor unit 20.

  The motor unit 20 is disposed on the outer peripheral surface side of the first casing 21 formed in a substantially bottomed cylindrical shape, and is disposed on the inner peripheral surface side of the first casing 21. And a rotating unit 27 that rotates freely around a predetermined rotation axis J1. The rotating part 27 is arranged in a space communicating with the pump chamber 30, and the pump in which the fixing part 22 is arranged by being cut off from the pump chamber 30 by a member like the first casing 21 is called a can pump. In addition, let the longitudinal direction of the rotating shaft J1 be an axial direction.

  The fixed portion 22 is disposed on the stator 22a in which a coil is formed by winding a winding around a stator core formed by laminating a plurality of electromagnetic steel plates via an insulator, and is disposed on the lower side in the axial direction of the stator 22a. Circuit board 22b to which the part is electrically connected. In addition to the circuit board 22b, a control IC for detecting and controlling the rotational position of the rotating portion 27 by detecting a counter electromotive force generated by the coil of the energized stator 22a, a connector for connecting to an external power source, etc. Has been implemented. The stator 22a and the circuit board 22b of the fixed portion 22 are molded with a resin substantially without a gap, thereby forming a bottomed cylindrical molded resin body. Insulation can be improved.

  Further, the first casing 21 includes a bottomed cylindrical portion 21a attached to the center inner peripheral surface of the fixed portion 22, a boss portion 21b that rises at the center bottom portion of the bottomed cylindrical portion 21a, and a bottomed cylindrical portion 21a. And a flange portion 21c extending to the open end. A concave portion 21b1 is provided on the upper surface of the boss portion 21b, and a lower end portion of a cylindrical shaft 23 coaxial with the rotation axis J1 is fitted therein. The upper end of the shaft 23 is fitted in a recess 25a of a third casing 25 that forms a pump chamber 30 together with the first casing 21 and a second casing 24 described later. Therefore, both ends of the shaft 23 are fixed to the first and third casings 21 and 25, respectively, and pass through the pump chamber 30. When both ends of the shaft 23 are held in this way, the axial rigidity of the pump 10 is improved, and the rotating portion 27 and two impellers described later can be stably rotated.

  The rotating portion 27 includes a substantially cylindrical rotor magnet 27a facing the inner peripheral surface of the stator 22a, a lower sleeve bearing member 27b that is rotatably fitted while sliding on the lower outer peripheral surface of the shaft 23, And a rotor holder portion 27c for integrally holding these members by insert molding. The rotor holder portion 27c further includes a first impeller 28 that is integrally formed as a part thereof. The first impeller 28 has a second impeller 29 disposed on the upper side thereof, and is connected by an engaging portion 289 in which both are engaged. The second impeller 29 integrally holds an upper sleeve bearing member 27d that is rotatably fitted while sliding on the upper outer peripheral surface of the shaft 23 by insert molding.

  As described above, the rotating portion 27 including the first and second impellers 28 and 29 is rotatably supported in the pump chamber 30 with respect to the shaft 23 via the upper and lower sleeve bearing members 27d and 27b. Yes. In addition, annular thrust members 23a and 23b made of a highly-lubricating material are fitted to both ends of the shaft 23, and are respectively attached to the lower end surface of the lower sleeve bearing member 27b and the upper end surface of the upper sleeve bearing member 27d. By abutting slidably, the movement of the rotating portion 27 in the axial direction is restricted. The rotating portion 27 generates a rotational torque due to the interaction between the magnetic flux generated from the stator 22a when the coil is energized and the magnetic flux of the rotor magnet 27a, and rotates around the rotation axis J1. By changing the method, it is possible to rotate in either the forward direction or the reverse direction. Such a motor rotating in both directions is called a reversible motor or a reversible motor.

[Pump chamber structure]
The pump chamber 30 will be described with reference to FIGS. 3 is a cross-sectional view seen from the motor unit 20 side when cut along the cutting line Y1-Y1 in FIG. 2, and FIG. 4 is a view seen from the motor unit 20 side when cut along the cutting line Y2-Y2 in FIG. FIG.

  The second casing 24 includes a cylindrical portion 24a that is combined with the flange portion 21c of the first casing 21, a partition wall portion 24b that divides the internal space of the cylindrical portion 24a vertically into a substantially intermediate portion in the axial direction of the cylindrical portion 24a, Is provided. An engaging portion 289 that connects the first and second impellers 28 and 29 together with the shaft 23 is inserted into the partition wall portion 24b, and a communication portion 24b1 that connects the upper space and the lower space of the cylindrical portion 24a. Is provided. The space formed by the lower surface of the partition wall portion 24b (the surface on the motor portion 20 side), the inner peripheral surface of the cylindrical portion 24a, and the inner surface of the bottomed cylindrical portion 21a of the first casing 21 is a first impeller 28. And the 1st storage chamber 30a which accommodates the rotation part 27 is comprised. On the contrary, the space formed by the upper surface of the partition wall portion 24b, the inner peripheral surface of the cylindrical portion 24a, and the lower surface of the third casing 21 constitutes a second storage chamber 30b that stores the second impeller 28. Furthermore, the space formed by the communication portion 24b1 constitutes a communication chamber 30c. The pump chamber 30 including the first and second storage chambers 30a and 30b and the communication chamber 30c constitutes one closed space that communicates with each other.

  As shown in FIG. 3, the first storage chamber 30a is a spiral space that extends clockwise around the rotation axis J1, and the first accommodation chamber 30a communicates with the external space of the cylindrical portion 24a at a position farthest from the rotation axis J1. One discharge port 24c is provided. The first discharge port 24c has a pipe shape that is orthogonal to the rotation axis J1 and that is inclined upward with respect to the right side in the horizontal direction in FIG. 3, and is connected to a second circulation pipe 59 that forms a circulation function in the washing machine. .

  Further, as shown in FIG. 4, the second storage chamber 30b is a spiral space that spreads counterclockwise around the rotation axis J1, and is located at a position farthest from the rotation axis J1 with the external space of the cylindrical portion 24a. A second discharge port 24d that communicates is provided. The second discharge port 24d has a pipe shape orthogonal to the rotation axis J1 and inclined upward with respect to the left side in the horizontal direction in FIG. 4, and is connected to a discharge pipe 60 that performs a discharge function in the washing machine.

  Furthermore, as shown in FIG. 2, the communication chamber 30c is provided with a water inlet 24e that communicates with the external space of the cylindrical portion 24a. As shown in FIG. 3, the water suction port 24 e has a pipe shape that is orthogonal to the rotation axis J <b> 1 and extends upward in FIG. 3, and is connected to a first circulation pipe 58 in the washing machine. Therefore, the pump 10 is arranged such that the rotation axis J1 is oriented in the horizontal direction and the water inlet 24e is opened in the antigravity direction.

  The water taken into the pump chamber 30 is a gap formed by the inner peripheral surface of the lower sleeve bearing member 27b of the motor unit 20 and the outer peripheral surface of the shaft 23, and the inner peripheral surface of the upper sleeve bearing member 27d and the shaft 23. A gap formed by the outer peripheral surface, a gap formed by the lower end surface of the lower sleeve bearing member 27b and the upper surface of the thrust member 23a, and an upper surface of the upper sleeve bearing member 27d and the lower surface of the thrust member 23b. It also intervenes in the gap. Therefore, water acts as a lubricating fluid, and lubricity between the upper and lower sleeve bearing members 27d and 27b and the shaft 23 and the thrust members 23a and 23b is improved.

[Impeller structure]
The first and second impellers 28 and 29 will be described with reference to FIGS. 5 is a plan view of the first impeller 28 viewed from the opposite side of the motor unit 20, and FIG. 6 is a plan view of the second impeller 29 viewed from the opposite side of the motor unit 20.

  As shown in FIGS. 2 and 5, the first impeller 28 includes a disc portion 28a having a cylindrical insertion hole 28a1 through which the shaft 23 is inserted at the center coaxial with the rotation axis J1, and one of the disc portions 28a. Six auxiliary wings 28b arranged in a plane around the insertion hole 28a1 at equal intervals in the circumferential direction, and six auxiliary wings arranged at equal intervals in the circumferential direction on the radially outer side between the adjacent main wings 28b. A centrifugal impeller that extrudes water absorbed at the center to the outer diameter side. The main wing 28b has a plate shape curved in a letter “V” in a plan view in FIG. 5, and has an arcuate blade inner diameter portion 28b1 approaching the rotation axis J1 toward the rotation direction of the arrow CCW, and the rotation axis It consists of an arcuate blade outer diameter portion 28b2 along the circumferential direction of a circle C1 centered on J1.

  When the first impeller 28 rotates counterclockwise in FIG. 5 (the direction of the arrow CCW, the forward rotation direction of the motor unit 20), the blade inner diameter portion 28b1 of the main wing 28b is formed in a direction intersecting the circle C1. Therefore, the outer surface of the blade inner diameter portion 28b1 scrapes water to the outer diameter side. That is, the outer surface of the blade inner diameter portion 28b1 constitutes a liquid extrusion portion that pushes water to the outer diameter side. The water thus scraped out also acts as a centrifugal force and is pushed out from the main wing 28b to the outer diameter side (see arrow f1). Following this flow, the water on the inner diameter side of the main wing 28b is absorbed by the main wing 28b. The water absorption or pushing action of the main wing 28b is performed by each main wing 28b, whereby the first impeller 28 has a pumping action of sucking water from the center and pushing it radially. At this time, the blade outer diameter portion 28b2 and the auxiliary wing 28c of the main wing 28b are shaped along the circumferential direction of the circle C1, so that the resistance to water is small and there is almost no action of scavenging water. Further, the auxiliary wing 29c is provided at a position deviating from the traveling direction of the water scraped from the main wing 28b (the auxiliary wing 29c is not provided near the tip of the arrow f1 in FIG. 5). The flow of water extruded from the main wing 28b is not obstructed.

  On the other hand, when the first impeller 28 rotates clockwise (in the direction of the arrow CW, the reversal direction of the motor unit 20), the inner side surface of the blade inner diameter portion 28b1 of the main wing 28b acts to scrape water to the outer diameter side. However, since the inner side surface of the blade outer diameter portion 28b2 of the main wing 28b is formed along the circumferential direction, the water toward the outer diameter side returns from the circumferential direction to the inner diameter side (see arrow f2). That is, the inner side surface of the blade outer diameter portion 28b2 constitutes a first liquid suppressing portion that suppresses the flow of water toward the outer diameter side. Even if the water does not return to the inner diameter side and passes through the blade outer diameter portion 28b2 of the main wing 28b, it is blocked by the auxiliary wing 28c, so that there is almost no water pushed out from the impeller. That is, the inner side surface of the auxiliary wing 28c constitutes a second liquid suppressing portion that suppresses the flow of water toward the outer diameter side. That is, the clockwise first impeller 28 is configured to prevent the flow of water toward the outer diameter side by the main wing 28b and the auxiliary wing 28c. Therefore, the first impeller 28 has an extremely small amount of water pushed out to the outer diameter side in the clockwise direction as compared with the counterclockwise direction (that is, the first impeller 28 has a lifting force or The flow rate is larger than when reversing.)

  On the other hand, as shown in FIG. 6, the second impeller 29 has substantially the same configuration as the first impeller 28 except that the upper sleeve bearing member 27d is included in the central insertion hole (for convenience of description). The reference numerals of the respective parts of the second impeller 29 are the disc part 29a, the insertion hole 29a1, the main wing 29b, the blade inner diameter part 29b, the blade outer diameter part 29b2, and the auxiliary blade 29c.) Therefore, among the molds used for molding the first and second impellers 28 and 29, at least the side on which the wings of the disk portions 28a and 29a are provided can be shared, and the mold cost can be reduced. it can. Moreover, if the wing | blade part containing the disk parts 28a and 29a is comprised with another member among the 1st, 2nd impellers 28 and 29, a wing | blade member can also be used as a common component.

  The first and second impellers 28 and 29 are connected so that the end portions of both insertion holes 28a1 and 29a1 constitute an engaging portion 289 so that the surfaces provided with the blades face each other. Therefore, although the first and second impellers 28 and 29 rotate in the same direction as the rotating unit 27, the arrangement direction of the main wing 29 b and the auxiliary wing 29 c of the second impeller 29 is reversed with respect to that of the first impeller 29. Therefore, the pumping action of the second impeller 29 shows the same tendency as that of the first impeller 28, but the presumed rotational direction is opposite (that is, the second impeller 29 is water that is pushed out to the outer diameter side in the counterclockwise direction. The extrusion amount is extremely small compared to the clockwise rotation, and the lifting force or flow rate at the time of reversal is larger than that at the time of normal rotation.)

  As a result, as shown in FIG. 3, the pump 10 is installed so that the rotation axis J1 is directed horizontally and the water suction port 24e faces the antigravity direction, and water is taken into the pump chamber 30, When the motor unit 20 rotates in the forward direction, the first impeller 28 actively scrapes water, so that the scraped water flows along the inner peripheral surface of the first storage chamber 30a and is discharged from the first discharge port 24c. . At this time, the water in the second storage chamber 30b hardly discharges from the second discharge port 24c due to the water absorption action of the first impeller 28 in addition to the fact that the second impeller 29 has almost no pumping action. Therefore, in the pump 10 during normal rotation of the motor unit 20, the pump characteristic of the first discharge port 24c is extremely larger than that of the second discharge port 24d. On the other hand, when the motor unit 20 is reversed under the same conditions, the behavior of water is opposite to that described above, and the water is discharged from the second discharge port 24d and hardly discharged from the first discharge port 24c. Therefore, in the pump 10 when the motor unit 20 is reversed, the pump characteristic of the second discharge port 24d is extremely larger than that of the first discharge port 24c.

  In this way, the pump 10 can switch the water taken into the pump chamber 30 via the water suction port 24e to any one of the first and second discharge ports 24c and 24d only by switching the rotation direction of the motor unit 20. Only one can be selected and discharged.

  On the other hand, the centrifugal impeller 100 used in the conventional reversible pump has an arc shape in which the main wing 71 approaches the rotation axis J1 in the rotation direction of the arrow CCW, as shown in FIG. When the impeller 100 rotates counterclockwise (CCW), water is pushed out by the outer surface of the main wing 71 and flows to the outer diameter side (see f10). When the impeller 100 rotates clockwise (CW), the main wing 71 Water is pushed out by the inner surface and flows to the outer diameter side (f11). That is, although there is a difference in the pushing force for pushing water to the outer diameter side when the main wing 71 rotates forward or reverse, the main wing 71 is pushed to the outer diameter side regardless of the direction of rotation. Thus, the flow of water toward the outer diameter side cannot be suppressed. When such an impeller 100 is applied to the pump 10, water is pushed out regardless of the direction of rotation and discharged from both the discharge ports 24 c and 24 d.

  Incidentally, the first and second impellers 28 and 29 are also devised as follows. Hereinafter, since the blade arrangement of both the impellers 28 and 29 is substantially the same, the description will be made using the first impeller 28.

  In FIG. 5, the inner diameter end of the blade inner diameter portion 28b1 of the main wing 28b in the first impeller 28 and the outer diameter end of the blade outer diameter portion 28b2 of the other main wing 28b adjacent to the outer diameter side of the blade inner diameter portion 28b1 are as follows. It is substantially located on a straight line L1 extending in the radial direction from the rotation axis J1.

  With such a configuration, the flow of water during normal rotation and reverse rotation of the first impeller 28 can be smoothly flowed to both. That is, when at least one of the inner diameter end of the blade inner diameter portion 28b1 of the main wing 28b and the outer diameter end of the blade outer diameter portion 28b2 of the main wing 28b adjacent thereto is formed longer and intersects the straight line L1, A gap 32 formed by the blade inner diameter portion 28b1 of the main wing 28b and the blade outer diameter portion 28b2 of the main wing 28b adjacent thereto is narrowed. Therefore, when the impeller rotates counterclockwise, when water absorbed from the center side flows to the outer diameter side (arrow f1), the flowing water resistance passing through the gap 32 increases, and the amount of water extrusion decreases. To do. Further, when the impeller rotates clockwise, water that attempts to return to the center side by the inner side surface of the blade outer diameter portion 28b2 of the main wing 28b (arrow f2), and other adjacent to the inner diameter side of the blade outer diameter portion 28b2 It is hindered by the outer surface of the blade inner diameter portion 28b1, and is difficult to return to the center side. On the other hand, in the configuration in which the inner diameter end of the blade inner diameter portion 28b1 of the main wing 28b is separated from the straight line L1 (the configuration in which the blade inner diameter portion 28b1 is shortened), the working surface as the liquid extruding portion is reduced. In the configuration in which the pushing force pushed out to the outer diameter side is weak and the blade outer diameter portion 28b2 is away from the straight line L1 (the configuration in which the blade outer diameter portion 28b2 is shortened), the working surface as the first liquid suppressing portion is small. Therefore, the action of returning water to the center side during clockwise rotation is weakened.

  Further, the front end of the auxiliary wing 28c in the counterclockwise direction is located slightly intersecting with the same straight line L1. If the front end of the auxiliary wing 28c is formed longer, the flow (f1) of water that has passed through the outer surface of the blade outer diameter portion 28b2 may be hindered when the impeller rotates counterclockwise. Further, the front end of the auxiliary wing 28c in the counterclockwise direction exceeds a tangent line T1 defined when the inner diameter end of the outer surface 28b2 of the blade adjacent to the inner diameter side of the auxiliary wing 28c is viewed in plan view. Located in no range. When counterclockwise, most of the water flow (f1) extruded from the outer surface of the main wing 28b is pushed out along the outer surface of the blade inner diameter portion 28b1, and therefore flows in the counterclockwise front of the tangent T1. Therefore, if the counterclockwise front end of the auxiliary wing 28c does not exceed the tangent line T1, the flow of water (f1) pushed out from the main wing 28b during the counterclockwise rotation is less likely to be hindered by the auxiliary wing 28c. Flows smoothly.

  On the other hand, if the front end of the auxiliary wing 28c is formed so as not to cross the straight line L1, the flow of water (f3) that has passed through the outer diameter portion 28b2 of the impeller when the impeller rotates clockwise is the same as that of the auxiliary wing 28c. It flows out of the impeller through the gap between them, and the flow of water to the outer diameter side cannot be sufficiently suppressed (that is, the function as the second liquid suppressing portion is reduced).

  Further, if the rear end of the auxiliary wing 28c in the counterclockwise direction is formed longer, the flow (f1) of water pushed out from the blade inner diameter portion 28b1 in the counterclockwise direction of the impeller may be hindered. The rear end is preferably within a range that does not exceed the tangent line T2 defined when the outer diameter end of the outer surface of the blade outer diameter portion 28b2 adjacent to the inner diameter side of the auxiliary blade 28c is viewed in plan view. On the other hand, if the rear end is formed shorter, the flow of water (f3) flowing through the blade outer diameter portion 28b2 and flowing to the outer diameter side when the impeller is rotated clockwise cannot be sufficiently suppressed (that is, The action as the second liquid suppressing portion is reduced.)

  Thus, in the first impeller 28, the pushing force for pushing water to the outer diameter side when rotating in the forward direction is extremely smaller than the pushing force for water when rotating in the reverse direction, and the second impeller 29 is The main wings 28b and 29b and the auxiliary wings 28c and 29c are configured so that the pushing force for pushing water to the outer diameter side during rotation in the reverse direction is extremely smaller than the pushing force for water during rotation in the forward rotation direction. The position and length relationships are optimized. Even if the positional relationship between the adjacent main wings 28b and the positional relationship between the main wings 28b and the auxiliary wings 28c are deviated, the effects of the present invention are exhibited.

[Relationship between pump and washing machine]
The pump 10 is installed on the bottom rear surface side of the outer tub 53 of the washing machine 50 so that the rotation axis J1 faces in the horizontal direction and the water suction port 24e faces in the antigravity direction, and the water suction port 24e is first circulated. Pipe 58, first discharge port 24c is connected to second circulation pipe 59, and second discharge port 24d is connected to discharge pipe 60. Therefore, the water in the outer tub 53 is supplied to the pump chamber 30 through the first circulation pipe 58 and the water inlet 24e by its own weight.

  When the circulation function is executed in the washing machine 50, the motor unit 20 of the pump 10 is rotated forward to discharge water from the first discharge port 24c (corresponding to the first discharge mode). Then, the water in the outer tub 53 of the washing machine 50 is supplied from the first circulation pipe 58 to the pump chamber 30 through the water inlet 24e of the pump 10, and further from the first discharge port 24c to the second circulation pipe. It is supplied again to the outer tub 53 via 59 (see arrow r1 in FIG. 1). On the other hand, when executing the discharge function, the motor unit 20 of the pump 10 is reversed and water is discharged from the second discharge port 24d (corresponding to the second discharge mode). Then, the water in the outer tub 53 of the washing machine 50 is supplied from the first circulation pipe 58 to the pump chamber 30 via the water suction port 24e of the pump 10, and further, the discharge pipe 60 is supplied from the second discharge port 24d. Through the apparatus (see arrow r2 in FIG. 1).

[Features of pump and washing machine]
Since the pump 10 solves a plurality of discharge functions such as a circulation function and a discharge function by a single motor unit 20 which is a reversible motor having two impellers 28 and 29, a motor is provided for each impeller. The pump itself can be reduced in size as compared with the case where a pump provided with a pump or two pumps is used.

  In addition, the pump 10 discharges one discharge port by the first and second impellers 28 and 29 and uses it as a circulation function or a discharge function (from one discharge port). When water is discharged), a discharge mode in which almost no water is discharged from the other discharge port can be realized.

  Further, in order to realize a plurality of discharge functions such as a circulation function and a discharge function, three water suction / discharge ports (water suction port 24e and discharge ports 24c, 24d) are required for one pump chamber 30, so that the pump The structure of the pump chamber 30 in the pump 10 as compared with a pump having four water intake / discharge ports each having one water intake port and one discharge port in each pump chamber divided into two chambers. Can be simplified and miniaturized. With respect to the structure of the pump chamber 30, a switching valve for switching between two discharge ports is not required, and the structure can be simplified because a switching valve is not required or a structure for measures against water leakage from the switching valve is not required. At the same time, it can contribute to downsizing.

  Further, in this pump 30, since the communication chamber 30c is located between the first and second storage chambers 30a and 30b, the water taken in from the water inlet 24e quickly flows into any of the storage chambers. It is possible to smoothly perform various selective discharge forms.

  Furthermore, by installing the pump 10, the washing machine 50 can be reduced in size by reducing the number of pipes connecting the washing tub, the drainage unit, and the pump in addition to downsizing the pump itself. In addition, since the washing machine 50 performs the switching of the water flow for executing the circulation and discharge functions by the pump 50, a switching valve for switching the water flow to each pipe connected to the pump 50 becomes unnecessary. Therefore, the washing machine 50 can be reduced in size and weight, and the cost can be reduced by assembling the washing machine and reducing the number of parts.

[Other Embodiments]
As mentioned above, although it demonstrated using a washing machine as one embodiment of the centrifugal impeller and the centrifugal pump of the present invention, the scope of the present invention is not limited to this, and other liquid circulation devices (for example, tableware) It can also be applied to washing machines. In short, the centrifugal impeller of the present invention is configured to rotate forward and backward due to the structure of the pump, but requires a pumping characteristic when rotating in one direction and does not require a pumping characteristic when rotating in the other direction. It can be applied to such a pump.

The sectional view showing typically one embodiment of the liquid circulation device to which the pump concerning the present invention is applied. Sectional drawing which shows one Embodiment of the pump which concerns on this invention. The side view when it sees from the motor part side when the 2nd casing of the pump shown in FIG. 2 is cut | disconnected by the cutting line Y1-Y1. The side view when it sees from the motor part side when the 2nd casing of the pump shown in FIG. 2 is cut | disconnected by the cutting line Y2-Y2. The top view which shows the 1st impeller of the pump shown in FIG. The top view which shows the 2nd impeller of the pump shown in FIG. The top view which shows the conventional centrifugal impeller.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Pump 20 Motor 24c 1st discharge port 24d 2nd discharge port 24e Water absorption port 28 1st impeller 28a, 29a Disk part 28b, 29b Main blade 28c, 29c Auxiliary blade 28b1, 29b1 Blade inner diameter part 28b2, 29b2 Blade outer diameter part 29 Second impeller 30 Pump room

Claims (11)

In the centrifugal impeller used in forward and reverse rotation in the centrifugal pump,
A disc portion provided coaxially with the rotation axis;
A plurality of main wings provided radially on the rotation axis in the plane of the disc portion;
Have
The main wing has a liquid push-out portion that pushes liquid to the outer diameter side when the impeller rotates forward, and a first liquid suppression portion that suppresses the flow of liquid toward the outer diameter side when the impeller reverses. Centrifugal impeller characterized by The main wing has a blade inner diameter portion that approaches the rotating shaft side in the forward rotation direction when the impeller rotates forward.
The centrifugal impeller according to claim 1, wherein the liquid extruding part is formed on an outer surface of the blade inner diameter part. The main wing has a blade outer diameter portion extending in a circumferential direction around the rotation axis from an outer diameter end of the blade inner diameter portion,
The centrifugal impeller according to claim 1 or 2, wherein the first liquid suppression portion is formed on an inner surface of the blade outer diameter portion.   The inner diameter end of the main wing and the outer diameter end of another main wing on the outer diameter side of the main wing are substantially located on a radial straight line centering on the rotation axis. The centrifugal impeller according to any one of 1 to 3.   5. The disk portion according to claim 1, further comprising a second liquid suppressing portion that suppresses a flow of liquid toward the outer diameter side of the main wing when the impeller is reversed. The centrifugal impeller described in 1.   The centrifugal impeller according to claim 5, wherein the second liquid suppressing portion is a surface formed in a circumferential direction around the rotation axis.   A radial direction centering on the rotation axis is an end portion in the forward direction of the impeller in the forward direction of the impeller in the second liquid suppressing portion and an outer diameter end portion of the main wing adjacent to the inner diameter side of the second liquid suppressing portion. The centrifugal impeller according to claim 5, wherein the centrifugal impeller is substantially located on a straight line.   The forward end of the impeller in the forward direction of the impeller in the second liquid suppressing portion is defined when the outer diameter end of the outer surface of the main wing adjacent to the inner diameter side of the second liquid suppressing portion is viewed in plan view. The centrifugal impeller according to any one of claims 5 to 7, wherein the centrifugal impeller is located in a range not exceeding a tangent line.   The forward end of the impeller in the forward direction of the impeller in the second liquid suppressing portion is defined when the inner diameter end of the outer surface of the blade outer diameter portion close to the inner diameter side of the second liquid suppressing portion is viewed in plan view. The centrifugal impeller according to any one of claims 5 to 8, wherein the centrifugal impeller is located in a range not exceeding a tangent line. The centrifugal impeller according to any one of claims 1 to 9,
A reversible motor for rotating or reversing the centrifugal impeller, and
A pump chamber for housing the centrifugal impeller;
A water inlet for guiding liquid outside the pump chamber to the pump chamber;
A discharge port for guiding the liquid taken into the pump chamber to the outside of the pump chamber;
A centrifugal pump characterized by comprising: A first centrifugal impeller according to any one of claims 1 to 9;
A second centrifugal impeller according to any one of claims 1 to 9,
A reversible motor arranged in a direction in which the first centrifugal impeller and the second centrifugal impeller face each other or face each other;
A pump chamber for housing the first centrifugal impeller and the second centrifugal impeller;
A water inlet for guiding liquid outside the pump chamber to the pump chamber;
A first discharge port for guiding the liquid taken into the pump chamber to the outside of the pump chamber by the first centrifugal impeller;
A second discharge port for guiding the liquid taken into the pump chamber to the outside of the pump chamber by the second centrifugal impeller;
A centrifugal pump characterized by comprising:

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