JP2009057881A - Pump device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump device capable of preventing the application of a useless load to an impeller. <P>SOLUTION: In a pump room 3 of the pump device, a rear shroud 57 of the impeller 50 exists in a rear position distant from a suction port 22 more than a delivery port 26 in the rotational axis L direction of the impeller 50, but a front face 57a of the rear shroud 57 becomes an annular tapered surface 571 of obliquely inclining an outer peripheral side end part forward from a midway position in the radial direction. A plurality of blade-like projections 58 extending in the radial direction in the outer peripheral side end part of a rear surface 57b, are also formed in a plurality of places in the peripheral direction on the rear surface 57b of the rear shroud 57. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a pump device that sucks and discharges liquid by rotation of an impeller in a pump chamber.

Among various pump devices, a so-called centrifugal pump device rotates an impeller in a pump chamber by a motor mechanism, and in the pump chamber, sucks liquid sucked from an inlet opening at a position facing on one side in the rotation central axis direction of the impeller. It discharges from the discharge port opened on the outer peripheral side of the impeller. In such a centrifugal pump device, the impeller is radially extended from the rotation center side to the outer peripheral side on the disk-shaped rear shroud facing the suction port and the front surface located on the suction port side of the rear shroud. And a plurality of blade portions (see, for example, Patent Document 1).
JP 2005-351225 A

  However, when the impeller described in Patent Document 1 is used, a negative pressure is generated near the front of the rear shroud so as to synchronize with the rotation of the impeller, and due to the negative pressure, the impeller has an intake port side in the axial direction. The force to be pulled is added. For this reason, the rotation shaft connected to the impeller is subjected to a force that tends to be pulled toward the suction port in the axial direction or a force that tends to tilt with respect to the axial direction. There are problems such as a decrease in service life.

  In view of the above problems, an object of the present invention is to provide a pump device that can prevent an unnecessary load from being applied to an impeller.

  In order to solve the above-mentioned problems, in the present invention, in a pump device having a drive mechanism, an impeller that is rotationally driven by the drive mechanism, and a casing that defines a pump chamber in which the impeller is disposed, the casing includes A suction port that opens at a position facing one side of the impeller in the rotational center axis direction of the impeller in the pump chamber, and a discharge port that opens radially outward from the impeller in the pump chamber. The impeller includes a disk-shaped rear shroud facing the suction port, and a plurality of radially extending front ends located on the suction port side of the rear shroud from the rotation center side toward the outer peripheral side. The front surface of the rear shroud is bent or curved toward the front side.

  In the present invention, the liquid traveling toward the discharge port generates a negative pressure in the vicinity of the front of the rear shroud so as to synchronize with the rotation of the impeller, and due to the negative pressure, a force for pulling forward is applied to the impeller. However, since the outer peripheral side of the front surface of the rear shroud is bent or curved toward the front, the negative pressure generated near the front of the rear shroud is small. Moreover, since the outer peripheral side of the front surface of the rear shroud is bent or curved forward, the liquid flowing toward the discharge port applies a force that presses the impeller rearward against the outer peripheral side of the rear shroud. The force for pulling the impeller forward due to the negative pressure generated in the vicinity of the front and the force for pushing the outer peripheral side of the rear shroud rearward cancel each other. Therefore, the rotation shaft connected to the impeller is not subjected to a force that tends to be pulled toward the suction port in the axial direction or a force that tends to tilt with respect to the axial direction, thus preventing a decrease in bearing life. can do.

  In the present invention, the front surface of the rear shroud may employ a configuration in which an outer peripheral side end portion is an annular tapered surface inclined obliquely forward from a midway position in the radial direction.

  In the present invention, the outer peripheral edge of the rear shroud is located at a position that overlaps with the outer peripheral ends of the plurality of blade portions in the radial direction, or is positioned radially outward from the outer peripheral ends of the plurality of blade portions in the radial direction. The configuration can be adopted.

  In the present invention, a plurality of blade-like protrusions extending in the radial direction at the outer peripheral side end portion of the rear surface are formed at a plurality of locations in the circumferential direction on the rear surface of the rear shroud opposite to the suction port side. It is preferable. If comprised in this way, it can prevent reliably that a foreign material collects behind the impeller.

  In the present invention, in the impeller, a configuration in which the blade portion and the blade-like protrusion are formed at the same angular position can be employed.

  In the present invention, since the front surface of the rear shroud is bent or curved toward the front at the outer peripheral side, the negative pressure generated near the front of the rear shroud is small. Moreover, since the outer peripheral side of the front surface of the rear shroud is bent or curved forward, the liquid flowing toward the discharge port applies a force that presses the impeller rearward against the outer peripheral side of the rear shroud. The force for pulling the impeller forward due to the negative pressure generated in the vicinity of the front and the force for pushing the outer peripheral side of the rear shroud rearward cancel each other. Therefore, the rotation shaft connected to the impeller is not subjected to a force that tends to be pulled toward the suction port in the axial direction or a force that tends to tilt with respect to the axial direction, thus preventing a decrease in bearing life. can do.

  Embodiments of the present invention will be described below with reference to the drawings. In the following description, for convenience, the side on which the liquid is sucked and discharged by the pump device is the right side (one side in the rotation center axis direction), and the side on which the drive mechanism is disposed is the left side (the other side in the rotation center axis direction). Side).

(overall structure)
1 (a), (b) and (c) are respectively a right side view of a pump device to which the present invention is applied as viewed from the right side connected to the pipe line side, a longitudinal sectional view of the pump device, and a cover of the pump device. FIG. 1B is a left side view seen from the side, and FIG. 1B corresponds to the AA ′ cross-sectional view of FIG. 2 (a) and 2 (b) are perspective views of a cap arranged on the most one side of the rotation center axis of the impeller from the oblique right side of the casing of the pump device to which the present invention is applied, and the cap. It is the perspective view seen from the diagonal left side.

  1 (a), 1 (b), and 1 (c), the pump device 1 of the present embodiment is a centrifugal pump that is attached to a filter case in a washing machine, and liquid is supplied at the right side portion in the axial direction (rotation center axis L). Inhale and discharge. The pump device 1 includes a hollow casing 2. A pump chamber 3 is configured on the right side in the axial direction of the inside of the casing 2, and an impeller 50 in the pump chamber 3 is positioned on the left side of the pump chamber 3. A drive mechanism 70 for rotationally driving is arranged.

  The casing 2 includes a cup-shaped holder 30 (pump chamber side casing member) whose opening is directed to the left side at a substantially central portion in the axial direction, and a disk-shaped plate that is placed on the right side in the axial direction with respect to the cup-shaped holder 30. 20, and the pump chamber 3 is defined between the plate 20 and the bottom plate portion 35 of the cup-shaped holder 30. Accordingly, the plate 20 corresponds to a first casing member that defines a right side surface of the pump chamber 3 in the rotation center axis L direction, and the cup-shaped holder 30 is a left side surface of the pump chamber 3 in the rotation center axis L direction. This corresponds to the second casing member that defines

  The casing 2 includes a cup-shaped cover 40 that is put on the right side of the cup-shaped holder 30, and the cup-shaped cover 40 covers the drive mechanism 70 in the cup-shaped holder 30. That is, in this embodiment, the drive mechanism 70 employs an outer rotor structure in which the rotor 72 is disposed on the outside, and thus the rotor 72 that is a movable part is covered with the cover 40. In the present embodiment, a tray-shaped holder 60 (base member) on which the drive mechanism 70 is mounted is fixed inside the cup-shaped holder 30, and the cover 40 is fixed to the tray-shaped holder 60.

(Configuration of pump chamber 3 and impeller)
As shown in FIGS. 1 (a), 1 (b) and 2 (a), 2 (b), the plate 20 has a disc shape and has a conical surface that is recessed from the right side (outside) to the left side (inside) in the central portion. 21 is formed. For this reason, a frustoconical protrusion 210 is formed on the inner surface of the plate 20, and a suction port 22 that opens in the axial direction is formed at the center of the protrusion 210. Therefore, the plate 20 has a structure provided with a conical surface (conical surface of the protruding portion 210) that dents the peripheral edge of the suction port 22 toward the other side (left side) in the direction of the rotation center axis L. In the plate 20, substantially arc-shaped recesses 23 and 24 that are recessed from the right side (outside) to the left side (inside) are formed around the conical surface 21, and the left side of the plate 20 is formed by forming the recesses 23 and 24. Two arc-shaped convex portions 230 and 240 are formed on the inner surface located at.

  In the plate 20, when the plate 20 and the cup-shaped holder 30 are fixed by two screws 29, a hole 281 in which the head of the screw 29 is accommodated opens to the right side. In addition, when the plate 20 and the cup-shaped holder 30 are fixed to the plate 20 with the screws 29, a hole 282 into which a seat portion 351 that protrudes from the cup-shaped holder 30 toward the right side is fitted is provided at a position where the screw 29 is stopped. A small through hole through which the shaft portion of the screw 29 passes is formed in the bottom wall that partitions the two holes 281 and 282. Further, the seat portion 351 is formed with a screw hole so as to open toward the right side.

  In this embodiment, the pump chamber 3 is configured by a space surrounded by the convex portions 230 and 240, and the casing 2 has a radial direction in the pump chamber 3 due to a discontinuous portion where the two convex portions 230 and 240 are separated in the circumferential direction. Two discharge ports 26 opening on the outside are formed. Here, the two discharge ports 26 are formed at point-symmetric positions around an axis (rotation center axis L) passing through the suction port 22, and liquid is discharged in the direction indicated by the arrow M in FIG. Is done.

  As shown in FIG. 1B, the cup-shaped holder 30 extends from the outer periphery of the disc-shaped bottom plate portion 35 constituting the left side surface of the pump chamber 3 toward the left side in the axial direction. A cylindrical portion 36 and a flange portion 37 that expands outward at the tip edge of the cylindrical portion 36 are provided.

  A conical surface 33 is formed in the bottom plate portion 35 of the cup-shaped holder 30 (the bottom portion of the pump chamber 3). In this embodiment, the conical surface 33 is substantially parallel to the conical surface 21 of the plate 20 and the frustoconical protrusion 210. Due to the formation of the conical surface 33, the bottom plate portion of the cup-shaped holder 30 is formed with a protruding portion that protrudes in a truncated cone shape toward the left side, and the central portion of the protruding portion is a cylindrical portion 34. In the bottom plate portion 35 of the cup-shaped holder 30, the outer peripheral side of the conical surface 33 is an annular flat surface 39, and the seat portion 351 is formed on the annular flat surface 39.

  The cylindrical portion 34 of the cup-shaped holder 30 is provided with a connecting portion between a rotation shaft 721 of the drive mechanism 70 (described later) and the impeller 50. The impeller 50 includes a cylindrical coupling portion 51 in which the right end portion of the rotating shaft 721 is fixed inside, and a plurality of blade portions 52 that extend radially outward from the right end portion of the cylindrical coupling portion 51. A seal member 38 fitted and fixed to the cylindrical portion 34 is interposed between the cylindrical connecting portion 51 and the cylindrical portion 34 of the cup-shaped holder 30. A metal bush 56 is insert-molded on the impeller 50, and the outer diameter of the bush 56 is in contact with the inner diameter of the seal member 38, so that water does not directly touch the rotating shaft 721.

  In this embodiment, the impeller 50 has five blade portions 52, and the blade portions 52 are formed at equiangular intervals from the center of the impeller 50 (cylindrical connecting portion 51).

  In this embodiment, when the cup-shaped holder 30 and the plate 20 are fixed, the seat portion 351 formed on the annular flat surface 39 of the bottom plate portion 35 of the cup-shaped holder 30 is fitted in the hole 282 of the plate 20. In a state where the convex portions 230 and 240 of the plate 20 are in contact with the flange portion 29 of the cup-shaped holder 30, the screw 29 is fixed to the hole 281 of the plate 20. As a result, the cup-shaped holder 30 and the plate 20 are configured to be screwed on the outer peripheral side of the pump chamber 3.

  When the cup-shaped holder 30 and the plate 20 are fixed in this manner, the pump chamber 3 is defined between the cup-shaped holder 30 and the plate 20, and the pump chamber 3 is surrounded by the conical surface 33. The substantially entire blade portion 52 of the impeller 50 is disposed in the mortar-shaped space. Further, the discharge port 26 opens between the annular flat surface 39 of the cup-shaped holder 30 and the plate 20. The discharge port 26 is located on the outer peripheral side of the impeller 50 at a position shifted to the right side in the rotation center axis L direction from the impeller 50, in this embodiment, at a position shifted to the right side in the rotation center axis L direction from the conical surface 33. In FIG. 5, the conical surface 33 is opened at a position on an extension line toward the outer peripheral side.

  In the pump device 1 configured as described above, when the impeller 50 is rotationally driven by the drive mechanism 70, water is sucked into the pump chamber 3 from one side (right side) of the rotation center axis L through the suction port 22, and 2 Water is discharged from each of the two discharge ports 26.

  Here, the two discharge ports 26 are formed at point-symmetrical positions around the rotation center axis L, and the five blade portions 52 are arranged at equiangular intervals from the center of the impeller 50 (cylindrical coupling portion 51). Has been. For this reason, out of the five blade portions 52, none of the blade portions 52 passes through the position where the two blade portions 52 simultaneously face the two discharge ports 26 (the position closest to the discharge ports 26). For this reason, since the force applied to the impeller 50 and the rotating shaft 721 due to the passage of the blade portion 52 through the position facing the discharge port 26 can be reduced, the impeller 50 and the rotating shaft 721 are prevented from greatly vibrating. And generation of noise can be prevented.

  In addition, since the two discharge ports 26 are formed at point-symmetric positions with the rotation center axis L as the center, the impeller 50 and the rotation shaft 721 are brought into contact with the impeller 50 and the rotation shaft 721 due to the blade 52 being closest to the discharge port 26. Since the applied force is canceled on both sides centered on the impeller 50, the impeller 50 and the rotating shaft 721 can be prevented from vibrating greatly, and the generation of noise can be prevented.

  In addition, since the structure that directly prevents the occurrence of vibration of the impeller 50 and the rotating shaft 721 is employed, it is more effective than a secondary vibration prevention measure that reduces the generated vibration with a rubber damper or a weight. In addition, even when such a secondary vibration prevention measure is used in combination, the secondary vibration prevention measure can be simplified, so that the cost can be reduced.

  Note that the number of the blades 52 in each of the plurality of blade portions 52 and the conditions for the positions of the discharge ports 26 so as not to approach the discharge ports 26 at the same time are not limited to the above conditions, and other conditions are adopted. May be.

  Further, in this embodiment, a conical surface 33 is formed to dent the central portion of the pump chamber 3 to the left in the direction of the rotation center axis L, and the impeller 50 is disposed in a bowl-shaped space surrounded by the conical surface 33. Is adopted. For this reason, since the impeller 50 can be disposed close to the drive mechanism 70 by the depth of the mortar-shaped space, the rotation shaft 721 may be short. Therefore, generation of vibration when the impeller 50 rotates can be suppressed, and generation of noise and the like due to the vibration can be prevented.

  In addition, since the impeller 50 is disposed in a bowl-shaped space surrounded by the conical surface 33, the discharge port 26 is shifted to the right side in the rotation center axis L direction from the impeller 50 on the outer peripheral side of the impeller 50. Still, since the periphery of the impeller 50 is a conical surface 33, a sufficiently large centrifugal force can be applied to the water flow by the rotation of the impeller 50, and the impeller 50 is discharged through the discharge port 26 with a sufficient pressure.

  Further, since the discharge port 26 is opened at a position on the extension line to the outer peripheral side of the conical surface 33, the liquid discharge from the pump chamber 3 is smooth.

  Furthermore, in the casing 2, the plate 20 is formed with a conical surface 21 that dents the peripheral edge of the suction port 22 toward the other side (left side / impeller 50 side) in the rotation center axis L direction. The suction of the liquid into the chamber 3 and the discharge of the liquid from the pump chamber 3 are smooth.

[Detailed configuration of impeller 50]
FIGS. 3A and 3B are respectively a perspective view of the pump device to which the present invention is applied and a cover viewed from an oblique right side, and an explanatory view showing an enlarged cross section around the impeller. 4 (a), 4 (b), and 4 (c) are respectively a cross-sectional view of an impeller used in a pump device to which the present invention is applied, a perspective view of the impeller viewed obliquely from the right (obliquely forward), and an oblique view of the impeller to the left It is the perspective view seen from (diagonal back).

  As shown in FIGS. 3A and 3B, the impeller 50 includes a cylindrical connecting portion 51 in which a right end portion of the rotation shaft 721 is fixed inside, and a radial direction from the right end portion of the cylindrical connecting portion 51. And a plurality of blade portions 52 extending radially outward. Further, the impeller 50 includes a disk-shaped rear shroud 57 facing the suction port 22, the cylindrical connecting portion 51 extends rearward from the rear surface 57 b of the rear shroud 57, and the blade portion 52 extends from the front surface of the rear shroud 57. And extending radially from the center of rotation toward the outer periphery. Here, the rear shroud 57 has a function of guiding the water flow to the discharge port 26.

  In this embodiment, the blade portion 52 of the impeller 50 is disposed in a mortar-shaped space surrounded by the conical surface 33 in the pump chamber 3, and the discharge port 26 is an annular flat surface of the cup-shaped holder 30. There is an opening between 39 and the plate 20. For this reason, since the discharge port 26 is disposed at a position shifted to the right side in the rotation center axis L direction from the impeller 50 on the outer peripheral side of the impeller 50, the rear shroud 57 is arranged at the rotation center axis L of the impeller 50. It is in a rear position farther from the suction port 22 than the discharge port 26 in the direction.

  Here, in the impeller 50, the front surface 57a of the rear shroud 57 is bent or curved forward so that the outer peripheral side is close to the discharge port 26. More specifically, the front surface 57a of the rear shroud 57 is an annular tapered surface 571 whose outer peripheral side end portion is inclined obliquely forward from a midway position in the radial direction.

  In the impeller 50, the outer peripheral edge of the rear shroud 57 overlaps with the outer peripheral end portions of the plurality of blade portions 52 in the radial direction, or slightly outside the outer peripheral end portions of the plurality of blade portions 52 in the radial direction. In addition, the outer peripheral ends of the plurality of blade portions 52 do not protrude beyond the outer peripheral edge of the rear shroud 57.

  Further, on the rear surface 57b of the rear shroud 57, a plurality of blade-like projections 58 extending in the radial direction at the outer peripheral side end portion of the rear surface 57b are formed at a plurality of locations in the circumferential direction. In this embodiment, there are five blade portions 52 and blade-like projections 58, and the blade portions 52 and the blade-like projections 58 are formed at the same angular position.

  In the pump device 1 configured as described above, the liquid traveling toward the discharge port 26 generates a negative pressure near the front of the rear shroud 57 so as to synchronize with the rotation of the impeller 50, and the impeller 50 is caused by the negative pressure. Is applied with a force to pull forward. However, in this embodiment, since the outer peripheral side of the front surface of the rear shroud 57 is bent or curved forward, the negative pressure generated near the front of the rear shroud 57 is small. In addition, since the front surface of the rear shroud 57 is bent or curved toward the front, the liquid toward the discharge port 26 applies a force that presses the impeller 50 backward against the outer periphery of the rear shroud 57. Therefore, the force that pulls the impeller 50 forward due to the negative pressure generated near the front of the rear shroud 57 and the force that pushes the outer peripheral side of the rear shroud 57 backward cancel each other. Therefore, the rotation shaft 721 connected to the impeller 50 is not subjected to a force that tends to be pulled toward the suction port 22 in the rotation center axis L direction or a force that tends to tilt with respect to the rotation center axis L direction. Therefore, it is possible to prevent a decrease in the life of a bearing (sintered bearing 729 (see FIGS. 1B and 3B) held inside a bearing holder portion 61 described later).

  Further, the outer peripheral edge of the rear shroud 57 overlaps with the outer peripheral ends of the plurality of blade portions 52 in the radial direction, or is positioned radially outward from the outer peripheral ends of the plurality of blade portions 52 in the radial direction. The outer peripheral end portions of the plurality of blade portions 52 do not protrude outward from the outer peripheral edge of the rear shroud 57. Therefore, no foreign matter is caught in the blade portion 52.

  Further, since a plurality of blade-like projections 58 are formed on the rear surface 57b of the rear shroud 57, a water flow toward the outer peripheral side is generated behind the rear shroud 57, so that foreign matter accumulates behind the impeller 50. This can be surely prevented.

(Configuration of drive mechanism 70 and the like)
5 (a), (b), (c), (d), and (e) are right side views with the cover removed from the pump device to which the present invention is applied, and the rotor from the pump device is removed. The right side view of the state, the sectional view when the rotor is cut along the rotation center axis, the sectional view when the rotor is cut perpendicular to the rotation center axis, and the screw of the tray holder and the cup holder It is sectional drawing which expands and shows a fixed part. 6 (a), (b), (c), (d), (e), (f), (g), and (h) are tray holders used in the pump device to which the present invention is applied. The perspective view seen from diagonally right, the perspective view seen from the diagonal left side of the tray-like holder, the front view of the tray-like holder, the right side view, the left side view, the plan view, the BB ′ sectional view, and the CC ′ sectional view is there.

  In the pump apparatus 1, when viewed from the left side of the rotation center axis L with the cover 40 removed, as shown in FIG. 5A, the tray-shaped holder 60 disposed inside the cup-shaped holder 30, and the cup-shaped holder 30. When the rotor 72 is removed and the rotor 72 is removed, as shown in FIG. 5B, the three-phase stator of the drive mechanism 70 held by the tray-shaped holder 60 appears. 71 appears. The stator 71 and the rotor 72 constitute a brushless motor.

  As shown in FIGS. 1B and 6A to 6F, the tray-shaped holder 60 has a substantially rectangular flat plate portion 62 and a cylindrical shape protruding from the central portion of the flat plate portion 62 toward the left side. Bearing holder portion 61, a rectangular frame-like thin wall portion 63 protruding from the outer peripheral side of the flat plate portion 62 toward the left side, and an annular protrusion 64 protruding toward the right side from the outer peripheral edge of the flat plate portion 62. The tray-shaped holder 60 is fixed in the cylindrical portion 36 of the cup-shaped holder 30 by screws 601 fixed to the flat plate portion 62.

  In the tray-like holder 60, a rib 641 is formed on the right side surface of the flat plate portion 62 inside the annular protrusion 64. In the tray-shaped holder 60, a cylindrical seat portion 621 that protrudes toward the left side around the bearing holder portion 61 is formed in the region surrounded by the thin wall portion 63 on the left surface of the flat plate portion 62. A cylindrical protrusion 622 having a small protrusion on the tip surface is formed at a position spaced from the bearing holder portion 61. In addition, the tray-like holder 60 is formed with a connector mounting portion 66 that projects downward from the flat plate portion 62 into a substantially rectangular shape.

  Further, in the flat plate portion 62, a cylindrical portion 623 having a through hole is formed outside the thin wall portion 63. Further, as shown in FIG. 5 (e), on the annular flat surface 39 of the cup-shaped holder 30, on the side opposite to the side where the pump chamber 3 is formed, a position overlapping the through hole of the cylindrical portion 623 is provided. The bottomed seat portion 390 in which the screw hole 391 is formed is formed, and the screw 601 is screwed from the tray-shaped holder 60 side to the screw of the cylindrical portion 623 in a state where the tray-shaped holder 60 is stacked on the cup-shaped holder 30. If it stops in the hole 391, the tray-shaped holder 60 can be fixed to the cup-shaped holder 30. Here, the tip portion of the screw 601 does not reach the position overlapping the blade portion 52 of the impeller 50 in the rotation center axis L direction, but the screw hole 391 is formed to a position deeper than the tip portion of the screw 601. In the direction of the rotation center axis L, it reaches a position overlapping the blade portion 52 of the impeller 50.

  Thus, in this embodiment, when the tray-shaped holder 60 holding the drive mechanism 70 is fixed to the cup-shaped holder 30, the screw hole 391 and the blade portion 52 of the impeller 50 are partially connected in the direction of the rotation center axis L. Since they are stacked, the length of the pump device 1 in the direction of the rotation center axis L of the impeller 50 can be shortened.

  In the tray-shaped holder 60 configured as described above, around the bearing holder portion 61, the stator core 711 is fixed by screws in a state of being supported by the seat portion 621. In the stator core 711, a plurality of salient poles 710 extending toward the outer peripheral side are formed at equal angular intervals, and a coil 712 is wound around each of the plurality of salient poles 710.

  A pair of cylindrical sintered bearings are press-fitted and fixed inside the bearing holder 61 at spaced positions in the axial direction, and the rotating shaft 721 of the rotor 72 is rotatably supported in the hole of the sintered bearing. Has been. In this embodiment, the rotational speed of the rotor 72 is, for example, about 5000 rpm.

  As shown in FIGS. 1B, 5C, and 5D, in the rotor 72, the left end portion of the rotating shaft 721 is press-fitted and fixed to the center of the bottom of the cup-shaped rotor case 722. A cylindrical permanent magnet 723 is press-fitted and fixed inside the cylindrical portion 722 so as to face the salient pole 710 of the stator core 711 radially outward. Note that a washer is attached to the rotating shaft 721 at each outer position of the two sintered bearings.

  In this embodiment, since the number of blade portions 52 of the impeller 50 is five, the number of salient poles 710 (the number of slots) is set to nine in the three-phase stator 71, and the cylindrical permanent magnet 723. In this case, the total number of magnetic poles (number of magnetic poles) composed of S poles and N poles alternately arranged in the circumferential direction is set to 12. For this reason, the number of the blade portions 52 is the greatest common divisor of the number of magnetic poles and the number of salient poles 710 in the permanent magnet 723, which is a number avoiding an integral multiple of 3. That is, the maximum common divisor of the number of salient poles 710 (number of slots) of the stator 71 and the number of magnetic poles of the permanent magnet 723 is 3, but the number of the blade portions 52 of the impeller 50 is five. The number of 71 salient poles 710 (the number of slots) and the number avoiding an integral multiple of the greatest common divisor of the number of magnetic poles of the permanent magnet 723 are set.

  For this reason, the cycle of switching phases in the stator 71 (the cycle in which the coils 712 of each phase are energized) and the cycle in which the blade portion 52 is closest to the discharge port 26 are deviated. Therefore, with respect to the impeller 50 and the rotating shaft 721, the timing at which force is applied due to the blade 52 being closest to the discharge port 26 and the impeller 50, the rotating shaft 721 and the coil 712 when the phases are switched. The timing when force is applied is off. Therefore, it is possible to prevent vibrations and noise generated in the impeller 50, the rotating shaft 721, and the stator 71 from resonating with each other, so that generation of noise can be prevented.

  In addition, since the structure that directly prevents the occurrence of vibration of the impeller 50 and the rotating shaft 721 is employed, it is more effective than a secondary vibration prevention measure that reduces the generated vibration with a rubber damper or a weight. In addition, even when such a secondary vibration prevention measure is used in combination, the secondary vibration prevention measure can be simplified, so that the cost can be reduced.

  When the number of the blade portions 52 of the impeller 50 is set to a number that avoids an integer multiple of the number of salient poles 710 (number of slots) of the stator 71 and the greatest common divisor of the number of magnetic poles of the permanent magnet 723, The number of combinations is not limited, and other combinations may be employed.

(Configuration of connector 80 and substrate 75)
7 (a), 7 (b), and 7 (c) are perspective views of the connector mounting portion formed on the tray-like holder of the pump device to which the present invention is applied as viewed from the left side of the rotation center axis, and the connector mounting. FIG. 6E is a perspective view of the state where the female connector is mounted on the section when viewed from the left side of the rotation center axis, and the state of mounting the female connector on the tray-shaped holder is cut by HH ′ in FIG. It is a longitudinal cross-sectional view shown in FIG.

  As shown in FIGS. 1B, 5A, 5B, and FIGS. 7A, 7B, and 7C, the tray-shaped holder 60 has a substantially rectangular shape downward from the flat plate portion 62. A connector mounting portion 66 overhangs, and a female connector 80 is mounted on the connector mounting portion 66. Accordingly, the tray-shaped holder 60 corresponds to a support member for the female connector 80. In addition, a substrate 75 for supplying power to the coil 712 of the stator 71 is disposed inside the thin wall portion 63 between the flat plate portion 62 of the tray-shaped holder 60 and the stator core 711. The substrate 75 is welded to the tray-shaped holder 60 by melting the small protrusions with the small protrusions of the protrusions 622 of the tray-shaped holder 60 fitted in the small holes of the substrate 75. The substrate 75 has a motor control IC, a Hall element, and other electronic components mounted on the right side (back side). Further, the end of the coil 712 is soldered to the left surface (front surface) of the substrate 75 and the tip end portion of the lead wire 89 extending from the female connector 80 mounted on the connector mounting portion 66 is soldered. ing. Therefore, the lead wire 89 corresponds to a flexible electrical connection member for the substrate 75 as an electrical component. As the electrical connection member, a flexible substrate or the like can be used in addition to the lead wire 89.

  In the tray-like holder 60, the resin 9 is potted inside the thin wall portion 63 (concave portion) so as to cover the surface of the substrate 75, and the resin 9 is cured to seal the substrate 75. Has been done.

  In realizing such a configuration, the female connector 80 (first connector) used in this embodiment is connected to a male connector (not shown / second connector) as shown in FIG. A portion 82 is provided at the front end portion of the connector housing 81, and a plurality of lead wires 89 are provided from the rear end portion located on the side opposite to the coupling portion 82 in the male connector mounting direction (direction indicated by arrow F) It extends. The plurality of lead wires 89 include a power supply line and a control signal line. The female connector 80 includes a thin plate-like spring portion 85 that projects in a frame shape toward the left and right sides on the front end side of the connector housing 81.

  On the other hand, as shown in FIG. 1B and FIG. 7B, the tray-shaped holder 60 has the leading end of the lead wire 89 connected to the connector mounting portion 66 in the mounting direction of the female connector 80. The substrate 75 is held. Here, the substrate 75 is held by the tray-shaped holder 60 in a position parallel or substantially parallel to the mounting direction at a position where the surface 751 to which the lead wire 89 is connected is lower than the female connector 80 (on the right side of the rotation center axis L). The resin 9 is sealed. Accordingly, the lead wire 89 extends from the rear end surface of the connector housing 81, and then is bent at a substantially right angle toward the substrate 75 to extend to the surface of the substrate 75. Further, each of the plurality of lead wires 89 is curved at one place when viewed from the side, but when the connector mounting portion 66 is viewed from above, the plurality of lead wires 89 extend linearly.

  Here, as shown in FIGS. 6G and 6H and FIGS. 7A and 7B, the tray-shaped holder 60 holds the female connector 80 mounted on the connector mounting portion 66 from both the left and right sides. As a connector holding part, it has a pair of hook parts 67 that elastically deform by pressing the spring part 85 inward from the left and right sides, and a columnar protrusion 68 that positions the rear end side of the female connector 80 from both sides, Each of the pair of hook portions 67 rises on both the left and right sides of the connector mounting portion 66 and has a claw portion that automatically engages the female connector 80 when the female connector 80 is pressed toward the connector mounting portion 66. I have. Further, the tray-shaped holder 60 includes a protrusion 69 extending in the width direction (left-right direction) at a position near the rear end of the connector mounting portion 66, while the protrusion 69 is formed on the surface of the female connector 80 that overlaps the connector mounting portion 66. A recess 88 into which is fitted is formed.

  In order to mount the female connector 80 on the connector mounting portion 66 while being mounted on the tray-shaped holder 60 having such a configuration, first, the base end side of the lead wire 89 is connected to the female connector 80 by soldering, while the lead wire The tip end side of 89 is connected to the surface of the substrate 75 by soldering. Next, the substrate 75 is fixed on the tray-shaped holder 60. Next, as shown by the arrow G in the mounting direction of the female connector 80, when the connector mounting portion 66 is pressed so as to tilt the female connector 80 around the rear end side of the female connector 80, the female connector 80 is connected to the connector mounting portion 66. The spring portion 85 is pressed inward by the hook portion 67 and elastically deformed until the flat posture is reached, and automatically engages with a claw portion formed at the upper end of the hook portion 67. At this time, the connector housing 81 enters and positions inside the columnar protrusion 68, and the protrusion 39 formed on the connector mounting portion 66 fits into the recess 88 of the female connector 80. Thereafter, the resin 9 is potted so as to cover the surface of the substrate 75 in the recess formed inside the thin wall portion 63 of the tray-shaped holder 60, and the resin 9 is cured. As a result, the substrate 75 can be sealed, and the tray-shaped holder 60 can be reinforced with the resin 9.

  As described above, in this embodiment, the substrate 75 is fixed on the tray-like holder 60 with both ends of the lead wire 89 connected to the female connector 80 and the substrate 75, and then the female connector 80 is mounted on the connector mounting portion 66. In this case, the rear end surface of the female connector 80 from which the lead wire 89 is drawn is directed toward the board 75, and the connector mounting portion 66 has a male connector mounting direction (direction indicated by arrow F) and the female connector 80. Since the hook portion 67 for holding the female connector 80 is arranged in the direction (shown by the arrow G) crossing the mounting direction (shown by the arrow G), the female connector 80 is tilted around the rear end side of the female connector 80. Thus, the female connector 80 can be mounted on the connector mounting portion 66 of the tray-shaped holder 60 simply by pressing the female connector 80 against the connector mounting portion 66 from above. Can. Therefore, since the dimension of the lead wire 89 that connects the substrate 75 and the female connector 80 may be short, even when the lead wire 89 is routed in a narrow area around the rotating rotor 72, the rotor 72 and the lead wire 89 are in contact with each other. There is nothing to do. Further, since the female connector 80 disposed on the connector mounting portion 66 is sandwiched by the hook portion 67 on both sides in the mounting direction of the male connector, the female connector 80 can be easily fixed to the tray-shaped holder 60.

  In addition, since the female connector 80 and the board 75 are connected via the lead wires 89, the wiring pattern formed on the surface side of the board 75 and the terminals of the female connector 80 are electrically connected, and the board 75 is connected. Can be realized by simply placing a commercially available female connector 80 horizontally, and the cost of the pump device 1 can be reduced. That is, the female connector includes a horizontal mounting type and a vertical mounting type as mounting terminals that can be directly mounted on the board 75. In the vertical mounting type with mounting terminals, a male connector is provided near the surface of the board 75. On the other hand, there is a problem that it is necessary to secure a space for mounting. On the other hand, in the case of a commercially available horizontal type with mounting terminals, it is possible to seal the substrate 75 with potted resin due to the height dimension. The problem arises that it cannot be done and must be specially manufactured. However, according to the present embodiment, since the board 75 is arranged in a position that is lower than the female connector 80 in a posture in which the mounting direction of the male connector and the surface of the board 75 are parallel or substantially parallel, Even when the lead wire 89 extending from the connector 80 is connected to the substrate 75, even if the resin 9 is potted so as to cover the substrate 75, the female connector 80 is not covered with the resin 9. 75 seals can be performed. Therefore, it is not necessary to use a commercially available female connector, and even when a device that handles water like the pump device 1 is configured, it is not necessary to seal the substrate 75 with a separate member.

  In this embodiment, the spring portion 85 is formed in the connector housing 81 of the female connector 80. However, a structure in which the female connector 80 is clamped from both the left and right sides only by the elasticity of the hook portion 67 of the tray-like holder 60 may be adopted. Good. In this embodiment, the female connector 80 is mounted on the tray-shaped holder 60 as the first connector. However, the male connector may be mounted on the tray-shaped holder 60 as the first connector. In this case, a female connector is used as the second connector.

(Structure of cover 40 etc.)
8 (a), (b), (c), and (d) are perspective views of the cover used in the pump device to which the present invention is applied as seen from the oblique right side, perspective views of the cover as seen from the oblique left side, It is a left side view and a side view when the cover is viewed from the direction indicated by arrow E.

  In this embodiment, as can be seen from FIG. 1B, the drive mechanism 70 employs an outer rotor structure in which the rotor 72 is disposed on the outside, so that the coil 712 can be easily wound and is permanent. While there is an advantage that inexpensive ferrite can be used for the magnet 723, it is necessary to cover the rotor 72 which is a movable part with the cover 40. For this reason, when the stator 71 generates heat due to the motor current, the temperature in the cover 40 increases. In particular, in the case of the outer rotor structure, the stator 71 is covered with the rotor 72, so heat cannot be dissipated and the temperature of the stator 71 is likely to rise. Therefore, in this embodiment, a cover 40 having a structure to be connected as described below is used.

  As shown in FIGS. 8A, 8 </ b> B, 8 </ b> C, and 8 </ b> D, the cover 40 includes a bottomed cylindrical portion 41 that covers the rotor 72 with a predetermined gap and an opening of the cylindrical portion 41. It has a flange portion 44 that extends outward from the edge and a rectangular tube-shaped body portion 45 that extends to the right from the outer peripheral edge of the flange portion 44, and is screwed to the tray-like holder 60. Further, a notch 450 is formed in the body 45 on the lower end side of the cover 40, and a part of the flange portion 44 is bent in a rectangular shape toward the left side so as to expand the notch 450. ing. For this reason, the cover 40 covers the rotor 72 without contacting the female connector 80. Further, the cover 40 includes an overhanging portion 440 that covers the female connector 80 on the left side. However, since the overhanging dimension of the overhanging portion 440 is short, more than half of the female connector 80 is exposed from the cover 40.

  In addition, a lower through hole 461 is formed in a slit shape in the lower portion of the body portion 410 of the cylindrical portion 41 of the cover 40 so as to overlap with the female connector 80, and is directed from the lower through hole 461 in both the circumferential directions. The upper through hole 462 is formed in a slit shape at each of the positions shifted by about 90 °. For this reason, since the outside air enters and exits the inside and outside of the cover 40 through the lower through hole 461 and the upper through hole 462, the stator 71 of the drive mechanism 70 disposed inside the cover 40 can be cooled. In particular, in this embodiment, since the lower through-hole 461 and the upper through-hole 421 are formed at different height positions as the through-holes, air easily circulates and the stator 71 can be efficiently cooled. Here, the lower through-hole 461 and the upper through-hole 462 are portions that are simultaneously formed when the cover 40 is manufactured by resin molding.

  However, since the pump device 1 handles water, if water enters from the through holes (the lower through hole 461 and the upper through hole 462), it causes a problem such as a short circuit.

  Therefore, in this embodiment, hook-like protrusions 47 and 48 projecting in a hook shape obliquely downward are formed on both side portions of the body portion 410 of the cylindrical portion 41 of the cover 40 which are located slightly below the uppermost position. Is formed. The hook-like protrusions 47 and 48 are plate-like, and when the cover 40 is screwed to the tray-like holder 60, the edge of the hook-like protrusion 47 is a groove 309 ( (See FIG. 5B).

  In the cover 40 configured as described above, the upper side of the lower side through hole 461 and the upper side through hole 462 is covered with hook-shaped protrusions 47 and 48. Of the lower through hole 461 and the upper through hole 462, the upper through hole 462 is formed at the base portion of the hook-shaped protrusions 47 and 48. Further, in this embodiment, a rectangular rib-like frame-like protrusion 49 protruding so as to surround the entire periphery of the lower through hole 461 is formed on the body portion 410 of the cylindrical portion 41 of the cover 40.

  Therefore, in this embodiment, the hook-like protrusions 47 and 48 are formed so as to cover the upper side of the lower through-hole 461 and the upper through-hole 462. , 48, and does not reach the lower through hole 461 and the upper through hole 462. Accordingly, it is possible to prevent water from entering the cover 40 from the lower through hole 461 and the upper through hole 462.

  In addition, since the upper through-hole 462 is formed at the base portion of the hook-shaped protrusions 47 and 48, water can be reliably prevented from entering. In addition, since the lower through hole 461 is surrounded by a frame-shaped protrusion 49, water that has bounced off the floor surface or the like is reliably prevented from entering the cover 40 through the lower through hole 461. can do.

  In the above embodiment, the lower through hole 461 is formed in one place and the upper through hole 462 is formed in two places. However, the lower through hole and the upper through hole are formed in one place each. Alternatively, a structure in which the lower through-hole and the upper through-hole are formed at two locations, respectively, may be employed.

(Another configuration example of the cover 40)
FIG. 9 is a left side view of another cover 40 used in the pump device 1 to which the present invention is applied. Similarly to the cover 40 described with reference to FIG. 8, the cover 40 illustrated in FIG. 9 also extends to the outside from the bottomed cylindrical portion 41 that covers the rotor 72 via a predetermined gap and the opening edge of the cylindrical portion 41. And a flange portion 44. In addition, a lower through hole 461 is formed in the vicinity of the connector mounting portion 66 in the body portion 410 of the cylindrical portion 41 of the cover 40, and about 90 from the lower through hole 461 toward both sides in the circumferential direction. An upper through hole 462 is formed at each of the shifted positions. Further, an upper through hole 463 is formed in the body portion 410 of the cylindrical portion 41 of the cover 40 at a position slightly shifted from the uppermost position.

  In this embodiment, hook-shaped protrusions 47 and 48 projecting obliquely downward are formed on both side portions of the body portion 410 of the cylindrical portion 41 of the cover 40 that are located slightly below the uppermost position. The hole 462 has a structure formed at the base portion of the hook-shaped protrusions 47 and 48. Also, on the body portion 410 of the cylindrical portion 41 of the cover 40, hook-shaped protrusions 470 and 480 are formed in an umbrella shape at positions directly above the upper through-hole 463, and the upper through-hole 463 is formed as a hook-shaped protrusion. It is formed in the base part of the parts 470 and 480.

  Even in such a configuration, since the lower through-hole 461 and the upper through-holes 462 and 463 are formed in the casing 2, outside air enters and exits the cover 40. The mechanism 70 can be cooled. In addition, since the hook-shaped protrusions 47, 48, 470, and 480 are formed above the lower and upper through holes 461 and 462 and 463, when the water droops from above, 48, 470, and 480, and does not reach the upper lower through hole 461 and the upper through holes 462 and 463. Accordingly, it is possible to prevent water from entering the casing 2 from the through holes (the lower through hole 461 and the upper through holes 462 and 463).

(A), (b), (c) is a right side view of the pump device to which the present invention is applied as viewed from the right side connected to the pipe line side, a longitudinal sectional view of the pump device, and the pump device from the cover side. FIG. (A), (b) is the perspective view which looked at the cap arrange | positioned at the most one side of the rotation center axis line of an impeller from the diagonal right side among the casings of the pump apparatus to which this invention is applied, respectively, and the said cap diagonally left side It is the perspective view seen from. (A), (b) is the perspective view which removed the cover from the pump apparatus to which this invention is applied, respectively, and was seen from diagonally right, and explanatory drawing which expands and shows the cross section of the impeller periphery. (A), (b), (c) is a cross-sectional view of an impeller used in a pump device to which the present invention is applied, a perspective view of the impeller viewed obliquely from the right (oblique front), and an impeller obliquely left (oblique) It is the perspective view seen from back. (A), (b), (c), (d), (e) is a right side view of the pump device to which the present invention is applied, with the cover removed, and the rotor from the pump device removed. Right side view, cross-sectional view when the rotor is cut along the rotation center axis, cross-sectional view when the rotor is cut perpendicular to the rotation center axis, and a fixed portion by screws between the tray-shaped holder and the cup-shaped holder It is sectional drawing which expands and shows. (A), (b), (c), (d), (e), (f), (g), and (h) are each a tray-like holder used in a pump device to which the present invention is applied. It is the perspective view seen from the perspective, the perspective view which looked at the tray-shaped holder from the slanting left side, the front view of the tray-shaped holder, the right side view, the left side view, the top view, the BB ′ sectional view, and the CC ′ sectional view. (A), (b), (c) is a perspective view when the connector mounting portion formed on the tray-like holder of the pump device to which the present invention is applied is viewed from the left side of the rotation center axis, respectively. A perspective view of the state in which the female connector is mounted as viewed from the left side of the rotation center axis, and a state in which the female connector is mounted on the tray-like holder are schematically cut by HH ′ in FIG. It is a longitudinal cross-sectional view. (A), (b), (c), (d) is a perspective view of the cover used in the pump device to which the present invention is applied as seen from the diagonal right side, a perspective view of the cover from the diagonal left side, and the left side of the cover It is a side view when the figure and a cover are seen from the direction shown by arrow E. It is a left view of another cover used for the pump apparatus to which this invention is applied.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pump apparatus 2 Casing 3 Pump chamber 20 Plate 22 Inlet 26 Outlet 30 Cup-shaped holder 33 Conical surface 50 Impeller 52 Blade part 57 Rear shroud 58 Blade-shaped protrusion 60 Tray-shaped holder 70 Drive mechanism 72 Rotor 71 Stator 571 Rear shroud Tapered surface

Claims (5)

In a pump device having a drive mechanism, an impeller that is rotationally driven by the drive mechanism, and a casing that defines a pump chamber in which the impeller is disposed.
The casing has a suction port that opens at a position facing one side of the impeller in the rotation center axis direction of the impeller in the pump chamber, and a radially outward opening with respect to the impeller in the pump chamber. A discharge port is formed,
The impeller includes a disc-shaped rear shroud facing the suction port, and a plurality of blade portions extending radially from the rotation center side toward the outer peripheral side on the front surface of the rear shroud located on the suction port side. And
The pump device according to claim 1, wherein the front surface of the rear shroud is bent or curved at the outer peripheral side toward the front.   2. The pump device according to claim 1, wherein the front surface of the rear shroud is an annular tapered surface whose outer peripheral side end portion is inclined obliquely forward from an intermediate position in the radial direction.   The outer peripheral edge of the rear shroud is positioned to overlap with the outer peripheral end portions of the plurality of blade portions in the radial direction, or located radially outward from the outer peripheral end portions of the plurality of blade portions in the radial direction. The pump device according to claim 1, wherein the pump device is characterized.   A plurality of blade-like projections extending in the radial direction at the outer peripheral end of the rear surface are formed at a plurality of locations in the circumferential direction on the rear surface of the rear shroud opposite to the suction port side. The pump device according to any one of claims 1 to 3, wherein the pump device is characterized.   5. The pump device according to claim 4, wherein in the impeller, the blade portion and the blade-like protrusion are formed at the same angular position.

Images