JP2010090751A - Pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump suppressing a flow rate of fluid delivered from a third delivery port while sufficiently securing the channel cross-sectional area of the third delivery port. <P>SOLUTION: This pump includes a pump housing 38 storing a blade member 43 rotatable in both normal and reverse directions around an axis S. The pump housing 38 is provided with a suction opening 45 for sucking cleaning water to the inside, a fluid passage 51 allowing the sucked cleaning water to flow in the same direction as the rotational direction of the blade member 43, a first delivery port and a second delivery port delivering the cleaning water from the fluid passage 51 to the outside of the pump housing 38 according to the rotational direction of the blade member 43, and the third delivery port 54 for delivering the cleaning water from the fluid passage 51 to the outside of the pump housing 38 when the blade member 43 is rotated. A vacuum area formed in the vicinity of the suction opening 45 in association with the rotation of the blade member 43 is made to serve as an inlet pressure area 46, and the third delivery port 54 has an overlap part 54a overlapping with the inlet pressure area 46 in an axis S direction. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pump mounted on, for example, a dishwasher.

  2. Description of the Related Art Conventionally, for example, a pump as shown in Patent Document 1 is known as a pump that is mounted on a dishwasher and used when washing dishes or draining sewage after washing. This pump includes a casing (pump housing), and an impeller (blade member) that can rotate in both forward and reverse directions based on the rotational drive of a motor is provided in the casing. Further, the casing has an inflow portion (suction port) for sucking washing water into the casing, and a first for supplying the washing water in the casing sucked from the inlet to the washing room side of the dishwasher. A circulation outflow part (third discharge port), a second circulation outflow part (first discharge part), and a pump drainage part for discharging the wash water in the casing sucked from the inflow port to the outside of the dishwasher ( A second discharge port).

  Further, in the casing, the pump drainage part is closed by rotating with the flow of the cleaning water when the impeller rotates forward, and the pump drainage by rotating with the flow of the cleaning water when the impeller reverses. A switching valve that opens the section is provided. When the impeller rotates forward to wash the tableware, the wash water sucked into the casing passes through the main flow path (fluid passage) in the casing in the same direction as the impeller rotation direction (forward rotation direction). The flushing water is discharged from the first circulation outflow portion and the second circulation outflow portion by closing the pump drainage portion by the switching valve. On the other hand, when the impeller rotates in the reverse direction to discharge the cleaning water, the cleaning water sucked into the casing flows in the same direction (reverse direction) as the impeller rotation direction through the main flow path in the casing. At the same time, the flushing water is discharged from the pump drainage by opening the pump drainage by the switching valve.

As described above, the pump of Patent Document 1 selects the washing water sucked into the casing from both the first circulation outflow portion and the second circulation outflow portion or the pump drainage portion by changing the rotation direction of the impeller. Can be discharged.
JP 2008-163822 A

  By the way, in the pump of patent document 1, when using the wash water discharged from the 1st circulation outflow part for the washing | cleaning of the float sensor for detecting the amount of washing water of a dishwasher, for example, the 1st circulation outflow part There was a possibility that the flow rate of the cleaning water discharged from the air would have an adverse effect on the detection accuracy of the float sensor. For this reason, if the flow passage cross-sectional area of the first circulation outflow portion is reduced to suppress the flow rate of the cleaning water discharged from the first circulation outflow portion, foreign matters are likely to be clogged in the first circulation outflow portion. There was a problem that.

  The present invention has been made in view of such circumstances. An object of the invention is to provide a pump capable of suppressing the flow rate of the fluid discharged from the third discharge port while sufficiently securing the flow path cross-sectional area of the third discharge port.

  In order to achieve the above object, according to the first aspect of the present invention, a vane member capable of rotating in both forward and reverse directions around a predetermined axis is accommodated in a pump housing, and the pump housing is based on the rotation of the vane member. A suction port for sucking fluid from outside the pump housing into the pump housing, a fluid passage for allowing fluid sucked from the suction port into the pump housing in the same direction as the rotation direction of the blade member, and the blade A first discharge port for discharging fluid from the fluid passage to the outside of the pump housing when the member rotates in one of the forward and reverse directions, and the blade member in the other direction of the forward and reverse directions A second discharge port for discharging fluid from the fluid passage to the outside of the pump housing when rotating, and at least one of the forward and reverse directions of the blade member In the pump provided with a third discharge port for discharging the fluid from the fluid passage to the outside of the pump housing when rotating in the direction, the blade member rotated in at least one of the forward and reverse directions In this case, the negative pressure region formed in the vicinity of the suction port is a suction pressure region, and the third discharge port is a portion overlapping the suction pressure region in the axial direction that is the rotation center of the blade member. The gist is that they have overlapping portions.

  According to this configuration, since the fluid flowing through the fluid passage is less likely to flow into the third discharge port, the fluid is discharged from the third discharge port to the outside of the pump housing while ensuring a sufficient flow path cross-sectional area of the third discharge port. It is possible to reduce the amount of fluid.

  According to a second aspect of the present invention, in the pump according to the first aspect, the overlapping portion is discharged from the third discharge port when the blade member rotates in one of the forward and reverse directions. A discharge amount difference for making a difference between the discharge amount of the fluid and the discharge amount of the fluid discharged from the third discharge port when the blade member rotates in the other of the forward and reverse directions. The gist is that the forming portion is provided.

  According to this configuration, the fluid discharged from the third discharge port by the discharge amount difference forming unit is more effective when the blade member is rotated in one of the forward and reverse directions than when rotated in the other direction. It is possible to increase or decrease the discharge amount.

  According to a third aspect of the present invention, in the pump according to the first or second aspect, at least one of the discharge pressure regions formed in the vicinity of the first discharge port and in the vicinity of the second discharge port. A communication passage communicating between the region and the suction pressure region is provided, and the third discharge passage is disposed at a position between the first discharge port and the second discharge port along the rotation direction of the blade member in the pump housing. The gist is that a discharge port is provided.

  According to this configuration, in a pump having no switching valve, when the fluid is sucked from the suction port and discharged from the first discharge port or the second discharge port, the suction pressure region becomes negative pressure and each discharge Since the pressure region becomes positive pressure, a portion where no suction pressure is generated is formed in the middle of the communication path because the fluid suction pressure (negative pressure) and the discharge pressure (positive pressure) cancel each other. For this reason, for example, when the blade member is rotated in one direction to discharge the fluid from the first discharge port, the fluid that tends to flow from the first discharge port side to the unintended second discharge port side has this pressure. Since it is circulated in the pump housing again by the portion that does not occur, the pump efficiency is lowered.

  In this regard, according to the present invention, in a pump that does not particularly have a switching valve, at least a part of the fluid that flows from the first discharge port side to the unintended second discharge port side flows from the third discharge port. It is discharged out of the pump housing. For this reason, since the quantity of the fluid circulated in the pump housing decreases again, it becomes possible to suppress a decrease in pump efficiency.

  Invention of Claim 4 is mounted in the washing machine which has the fluid quantity sensor for detecting the fluid quantity inside in the pump as described in any one of Claims 1-3. The gist is that the fluid discharged from the three discharge ports is used as a cleaning fluid for cleaning the fluid amount sensor.

  According to this configuration, by using the fluid discharged from the third discharge port as a cleaning fluid for cleaning the fluid quantity sensor, the foreign substance can be quickly washed away even if the foreign substance adheres to the fluid quantity sensor. Therefore, it is possible to maintain the accuracy of the fluid quantity sensor.

  According to the present invention, it is possible to suppress the flow rate of the fluid discharged from the third discharge port while sufficiently securing the channel cross-sectional area of the third discharge port.

(First embodiment)
Hereinafter, a first embodiment in which the present invention is embodied in a pump mounted on a dishwasher will be described with reference to the drawings.

  As shown in FIG. 1, a dishwasher 11 as a washing machine includes a washing body 13 for washing tableware D and a pump chamber 14 located below the washing room 13 in the machine body 12. Yes. That is, the cleaning chamber 13 and the pump chamber 14 are partitioned and formed by dividing the internal space of the machine body 12 up and down by the partition plate 15.

  The washing room 13 accommodates a tableware bowl 16 for arranging the tableware D, and the tableware bowl 16 is placed on a rail 17 extending in the horizontal direction so as to be slidable. A nozzle 18 for injecting cleaning water as a fluid into the cleaning chamber 13 when cleaning the tableware D is disposed in a lower portion of the cleaning chamber 13 in a manner rotatable around an axis extending in the vertical direction. Yes. A plurality of holes (not shown) are formed on the upper surface of the nozzle 18. Further, one end side of a cleaning pipe 19 extending vertically is connected to the lower surface of the nozzle 18, and the other end side of the cleaning pipe 19 is connected to a pump P disposed in the pump chamber 14 through the partition plate 15. Yes. When the cleaning water is supplied from the pump P through the cleaning pipe 19 to the nozzle 18 by driving the pump P, the cleaning water is urged into the cleaning chamber 13 from each hole (not shown) on the upper surface of the nozzle 18. The tableware D that is well sprayed and placed in the tableware bowl 16 is cleaned.

  On the left side of the cleaning chamber 13, there is provided an opening / closing door 20 that constitutes a part of the side wall of the machine body 12 and that can be opened and closed with respect to the machine body 12. The opening / closing door 20 is opened when the tableware D is placed in the tableware bowl 16 in the cleaning chamber 13 or when the tableware D after cleaning is taken out from the cleaning chamber 13, and is closed at other times. An injection passage 21 for injecting a predetermined volume of cleaning water into the cleaning chamber 13 from the outside of the machine body 12 is formed on the right side of the cleaning chamber 13, and cleaning is performed from the cleaning chamber 13 at the bottom of the cleaning chamber 13. An inlet 22 for allowing water to flow into the pump chamber 14 is provided. The inflow port 22 is provided with a filter F for removing leftover food and the like attached to the tableware D so as not to flow into the pump chamber 14 together with the washing water.

  The pump chamber 14 is provided with a storage tank 23 for storing cleaning water flowing down from the cleaning chamber 13 through the inlet 22. A pump P is disposed on the right side of the storage tank 23, and the pump P is connected to the storage tank 23 via a water absorption pipe 24. Therefore, the wash water once stored in the storage tank 23 is absorbed into the pump P from the horizontal direction via the water absorption pipe 24. Further, one end side of the drain pipe 25 is connected to the pump P, and the other end side of the drain pipe 25 extends through the side wall of the machine body 12 to the outside of the machine body 12. Then, by driving the pump P, the cleaning water is drained from the pump P to the outside of the machine body 12 through the drain pipe 25.

  Further, on the left side of the storage tank 23 in the pump chamber 14, a cleaning water tank 27 that communicates with the storage tank 23 via a communication pipe 26 is provided. The washing water tank 27 is provided with a water level sensor 28 as a fluid quantity sensor for detecting whether or not the washing water level (water quantity) in the washing water tank 27 is a predetermined value or more. The water level sensor 28 includes a float 29 disposed so as to float on the cleaning water in the cleaning water tank 27, and a detection unit 30 provided at the upper end of the cleaning water tank 27 and detecting the height of the float 29. The water level sensor 28 detects that the water level in the cleaning water tank 27 is equal to or higher than a predetermined value when the float 29 comes into contact with the detection unit 30, and the water tank when the float 29 does not come into contact with the detection unit 30. It is detected that the water level in 27 is less than a predetermined value.

  Further, the other end side of the discharge pipe 31 whose one end side is connected to the washing water tank 27 is connected to the pump P. When the cleaning water is supplied from the pump P to the cleaning water tank 27 through the discharge pipe 31 by driving the pump P, the supplied cleaning water is supplied by an injection device (not shown) provided in the cleaning water tank 27. By spraying on the float 29, dirt such as leftovers attached to the float 29 is washed away.

Next, the configuration of the pump P will be described in detail.
As shown in FIG. 2, the pump P includes a motor unit 35 and a pump unit 36. The motor unit 35 includes a motor M, and a rotor and a stator (both not shown) are disposed inside the motor M. A shaft 37 extending from the inside of the motor M (motor part 35) to the inside of the pump part 36 is fixed to the rotor. Then, the rotor can rotate in both forward and reverse directions around the axis 37 (predetermined axis) S of the shaft 37 together with the shaft 37 corresponding to the direction of current supplied from the power source (not shown) to the stator of the motor M. It has become.

  On the other hand, the pump portion 36 has a pump housing 38 having a substantially bottomed cylindrical shape with one end side (the right side in FIG. 1 and the left side in FIG. 2) opened, and a pump formed so as to be able to close the opening of the pump housing 38. A bracket 39 and a mounting plate 40 serving as a joining member to the motor unit 35 side are provided. The pump housing 38, the pump bracket 39, and the mounting plate 40 are integrally assembled with a plurality of (six in this embodiment) screws 41 with the pump bracket 39 in the center, and the mounting plate 40 in the integrally assembled state. Are fixed to the motor unit 35 by screws (not shown). That is, the pump unit 36 is integrally coupled to the motor unit 35.

  Through holes 39a and 40a through which the shaft 37 can be inserted are formed in the pump bracket 39 and the mounting plate 40. When the pump part 36 is integrally coupled to the motor part 35, the shaft 37 extends from the motor part 35 side. Is inserted into the through hole 40a of the mounting plate 40 and the through hole 39a of the pump bracket 39 to reach the inside of the pump housing 38. A plurality of annular (two in this embodiment) oil seals 42 are interposed on the peripheral surface of the shaft 37 between the mounting plate 40 and the pump bracket 39.

  A blade member (pump impeller) 43 is fixedly supported at the tip of the shaft 37 in the pump housing 38. The blade member 43 is configured to rotate integrally around the axis S together with the shaft 37 when the shaft 37 rotates based on the rotational drive of the motor M. In this case, the blade member 43 can rotate in the forward and reverse directions around the axis S of the shaft 37 together with the shaft 37 based on the rotational drive of the motor M. In addition, an O-ring 44 is interposed between the pump housing 38 and the pump bracket 39 when the pump portion 36 is integrally assembled, and the O-ring 44 suppresses the leakage of cleaning water from the pump housing 38. It is like that.

  As shown in FIGS. 3 and 4, the pump housing 38 is connected to the water absorption pipe 24 on the bottom wall portion 38 a, and flush water is supplied from the storage tank 23 into the pump housing 38 based on the rotation of the blade member 43. An inlet 45 for inhaling is provided. The suction port 45 is provided at a position on the axis S which is the rotation center of the blade member 43 in the bottom wall portion 38 a, and the axis line so as to suck cleaning water along the axis S into the pump housing 38. It protrudes in the direction along S. Therefore, when the blade member 43 rotates, as shown by a two-dot chain line in FIGS. 5 and 6, it is in the vicinity of the suction port 45 and on the front side of the blade member 43 (that is, the suction port 45 side). A suction pressure region 46 of a negative pressure atmosphere having substantially the same shape as the rotation trajectory of the outer peripheral edge of the blade member 43 is formed in the region.

  Further, the peripheral wall portion 38 b of the pump housing 38 is provided with a first discharge port 47 serving as a connection portion for the cleaning pipe 19 and a second discharge port 48 serving as a connection portion for the drain pipe 25. The pump housing 38 is configured to discharge the cleaning water in the pump housing 38 to the outside of the pump housing 38 via both discharge ports 47 and 48 based on the rotation of the blade member 43. Therefore, when the blade member 43 rotates, as shown by a two-dot chain line in FIGS. 3, 5, and 6, in the vicinity of the first discharge port 47 and the second discharge port 48 in the pump housing 38. Discharge pressure regions 49 and 50 having a higher pressure atmosphere than the suction pressure region 46 having a negative pressure atmosphere are formed in substantially the same shape as the opening shapes of the two discharge ports 47 and 48, respectively.

  Here, the second discharge port 48 is understood from the first discharge port 47 in the circumferential direction of the peripheral wall portion 38b (the rotation direction of the blade member 43) at a predetermined angle (in this embodiment, as understood from FIGS. 3 and 5). At approximately 90 degrees). In the direction along the axis S, the first discharge port 47 is provided closer to the blade member 43 than the suction pressure region 46, while the second discharge port 48 is provided closer to the suction port 45 than the suction pressure region 46. ing. The first discharge port 47 is provided at a position where the discharge pressure region 49 is formed in a region that does not overlap the suction pressure region 46 when viewed from the suction port 45 side in the direction of the axis S, and is orthogonal to the axis S. It is formed to protrude in the direction of On the other hand, the second discharge port 48 is provided at a position where a part of the discharge pressure region 50 is formed in a region overlapping the suction pressure region 46 when viewed from the suction port 45 side in the axis S direction. It is formed so as to protrude in a direction orthogonal to the axis S.

  As shown in FIGS. 3, 5, and 6, a fluid passage 51 for allowing the cleaning water to flow in the same direction as the rotation direction of the blade member 43 in the pump housing 38 is provided in the pump housing 38. It is formed in an arc shape along the inner peripheral surface of the portion 38b. The fluid passage 51 draws the cleaning water sucked into the pump housing 38 from the suction port 45 based on the rotation of the blade member 43 and made to flow toward the peripheral wall portion 38b by centrifugal force, from the first discharge port 47 and the second discharge port. A groove portion 52 is formed in the passage portion 51 a that guides water to the outlet 48 and communicates with the second discharge port 48. That is, the groove 52 constitutes a part of the fluid passage 51 in a passage portion 51 a that is a portion that communicates with the second discharge port 48 most recently in the fluid passage 51.

  The fluid passage 51 has a passage depth when viewed from the blade member 43 side in the passage portion 51a so as to continue to the second discharge port 48 located on the suction port 45 side of the suction pressure region 46 in the direction along the axis S. Is formed so as to gradually become deeper as it approaches the second discharge port 48. Further, in the passage portion 51a, the blade member 43 side is connected to the second discharge port 48 provided at a position where the discharge pressure region 50 is formed in a region inside the suction pressure region 46. When viewed from above, the passage width is formed so as to gradually become wider in the inner circumferential direction as it approaches the second discharge port 48. That is, as shown in FIG. 7, the fluid passage 51 is configured to communicate with the second discharge port 48 from the blade member 43 side through a part of the suction pressure region 46 in the passage portion 51 a (groove portion 52). Yes. Accordingly, a part of the groove 52 functions as a communication path G that communicates between the suction pressure region 46 and the discharge pressure region 50.

  As shown in FIG. 5, when the blade member 43 rotates in one of the forward and reverse directions (in the present embodiment, the direction indicated by the arrow A), the fluid passage 51 of the pump housing 38 from the suction port 45. The cleaning water sucked in is discharged from the first discharge port 47 to the cleaning tube 19 side and supplied into the cleaning chamber 13 through the cleaning tube 19. On the other hand, when the blade member 43 rotates in the other direction (in the present embodiment, the direction indicated by the arrow B) in both the forward and reverse directions, the wash water sucked into the fluid passage 51 of the pump housing 38 from the suction port 45. Is discharged from the second discharge port 48 to the drain pipe 25 side through the passage portion 51 a and drained to the outside of the machine main body 12 through the drain pipe 25.

  Further, a portion of the peripheral wall portion 38 b of the pump housing 38 between the first discharge port 47 and the second discharge port 48 in the circumferential direction is arranged so that the inner surface thereof is close to the outer peripheral edge of the blade member 43. The wall 38b is formed as an induction restricting portion 53 that is formed thick on the inner peripheral side. That is, in this portion, the fluid passage 51 is configured to be a narrow gap 51b that allows the blade member 43 to rotate. When the blade member 43 rotates in the direction indicated by the arrow A as shown in FIG. 5 due to the gap 51b being narrowed by the guide restricting portion 53, the first discharge port is formed along the fluid passage 51. It is difficult for washing water guided (guided) to the 47 side to flow to the second discharge port 48 side through the gap 51b. Similarly, since the clearance 51b is narrowed by the guide restricting portion 53, when the blade member 43 rotates in the direction indicated by the arrow B as shown in FIG. It is difficult for the washing water guided (induced) to the outlet 48 side to flow to the first discharge port 47 side through the gap 51b.

  In the position between the first discharge port 47 and the second discharge port 48 along the rotation direction of the blade member 43 in the pump housing 38, the blade member 43 is indicated by the direction indicated by the arrow A or the arrow B in FIG. A third discharge port 54 for discharging the wash water flowing through the gap 51b to the outside of the pump housing 38 when rotated in the direction is provided. The third discharge port 54 is located adjacent to the blade member 43 in the direction orthogonal to the axis S and at a position that does not overlap the suction pressure region 46 when viewed from the direction of the axis S. The third discharge port 54 is connected to the other end of a discharge pipe 31 (see FIG. 1) whose one end is connected to the cleaning water tank 27 (see FIG. 1), and is discharged from the third discharge port 54. The cleaning water is supplied to the cleaning water tank 27 through the discharge pipe 31.

Next, the operation of the pump P in the dishwasher 11 configured as described above will be described.
When supplying the cleaning water in the storage tank 23 to the cleaning chamber 13, first, the motor M is driven to rotate so that the blade member 43 rotates in the direction indicated by the arrow A in FIG. As a result, a suction pressure region 46 is formed in the vicinity of the suction port 45, and at the same time, a discharge pressure region 49 and a discharge pressure region 50 are formed in the vicinity of the first discharge port 47 and the second discharge port 48, respectively. The Then, by the action of the negative pressure in the suction pressure region 46, the wash water stored in the storage tank 23 flows through the water suction pipe 24 and is absorbed into the pump housing 38 of the pump P from the suction port 45. The washing water absorbed in the pump housing 38 is guided to the fluid passage 51 by the rotating blade member 43, and the fluid passage 51 is in the same direction as the rotation direction of the blade member 43 (the direction indicated by the arrow A in FIG. 5). To flow.

  The washing water flowing through the fluid passage 51 to the vicinity of the first discharge port 47 (discharge pressure region 49) is pumped from the first discharge port 47 to the pump P by the discharge pressure (positive pressure) of the discharge pressure region 49. It is discharged outside (cleaning tube 19). At this time, the suction pressure region 46 and the discharge pressure region 50 of the second discharge port 48 communicate with each other via the communication passage G (groove 52), and the communication passage G is in the middle (that is, with the suction pressure region 46). In the boundary portion between the discharge pressure region 50 and the discharge pressure (negative pressure) and the discharge pressure (positive pressure) cancel each other, a portion where no pressure is generated is formed.

  For this reason, even if part of the cleaning water that has flowed to the vicinity of the first discharge port 47 (discharge pressure region 49) flows to the vicinity of the second discharge port 48 through the gap 51b, the communication path G (groove 52) Since the water is again introduced into the suction pressure region 46 (recirculated into the pump housing 38), it is effective that a part of the washing water is discharged out of the pump housing 38 from the unintended second discharge port 48. It is suppressed. In this case, even if a part of the washing water is discharged from the second discharge port 48 to the outside of the pump housing 38 (drain pipe 25), the drain port 25a of the drain pipe 25 is located higher than the pump P (in this embodiment). Therefore, a part of the washing water is not discharged to the outside of the machine main body 12.

  Further, at least a part of the cleaning water flowing from the first discharge port 47 side through the gap 51 b to the second discharge port 48 side is discharged from the third discharge port 54. For this reason, the amount of the cleaning water flowing from the first discharge port 47 side to the second discharge port 48 side through the gap 51b is reduced by the amount discharged from the third discharge port 54. The amount of cleaning water introduced from the groove 52) to the suction pressure region 46 again is reduced. That is, since the amount of cleaning water circulated from the communication path G (groove 52) into the pump housing 38 is reduced again, a decrease in pump efficiency of the pump P is suppressed. Further, the cleaning water discharged from the third discharge port 54 is supplied to the cleaning water tank 27 through the discharge pipe 31 and then used as cleaning water (cleaning fluid) for cleaning the float 29. For this reason, since the float 29 is maintained in a clean state, the malfunction of the float 29 is suppressed, and the performance of the water level sensor 28 is maintained.

  On the other hand, when the washing water in the storage tank 23 is drained to the outside of the machine main body 12, first, the motor M is rotationally driven so that the blade member 43 rotates in the direction indicated by the arrow B in FIG. As a result, a suction pressure region 46 is formed in the vicinity of the suction port 45, and at the same time, a discharge pressure region 49 and a discharge pressure region 50 are formed in the vicinity of the first discharge port 47 and the second discharge port 48, respectively. The Then, by the action of the negative pressure in the suction pressure region 46, the wash water stored in the storage tank 23 flows through the water suction pipe 24 and is absorbed into the pump housing 38 of the pump P from the suction port 45. The washing water absorbed in the pump housing 38 is guided to the fluid passage 51 by the rotating blade member 43, and the fluid passage 51 is in the same direction as the rotation direction of the blade member 43 (the direction indicated by the arrow B in FIG. 5). To flow.

  The washing water flowing through the fluid passage 51 to the vicinity of the second discharge port 48 (discharge pressure region 50) is discharged from the second discharge port 48 to the drain pipe by the discharge pressure (positive pressure) of the discharge pressure region 50. 25 (outside the pump P) and discharged from the drain port 25a of the drain pipe 25 to the outside of the machine body 12. At this time, part of the cleaning water that has flowed to the vicinity of the second discharge port 48 (discharge pressure region 50) flows to the vicinity of the first discharge port 47 through the gap 51b. In this case, at least a part of the cleaning water flowing from the second discharge port 48 side through the gap 51 b to the first discharge port 47 side is discharged from the third discharge port 54. Then, the cleaning water discharged from the third discharge port 54 is supplied to the cleaning water tank 27 through the discharge pipe 31 and then used as cleaning water for cleaning the float 29. For this reason, since the float 29 is maintained in a clean state, the malfunction of the float 29 is suppressed, and the performance of the water level sensor 28 is maintained.

According to the first embodiment described in detail above, the following effects are exhibited.
(1) Normally, when the pump P is driven and the cleaning water is sucked from the suction port 45 and discharged from the first discharge port 47 or the second discharge port 48, the suction pressure region 46 becomes negative pressure and each discharge pressure Since the regions 49 and 50 have a positive pressure, a portion where the suction pressure (negative pressure) and the discharge pressure (positive pressure) of the cleaning water cancel each other is formed in the middle of the communication path G. Therefore, for example, when the blade member 43 is rotated in the direction indicated by the arrow A in FIG. 5 and the cleaning water is discharged from the first discharge port 47, it is not intended from the first discharge port 47 side through the gap 51b. Since the wash water which is about to flow toward the second discharge port 48 is circulated again into the pump housing 38 by the portion where the pressure formed in the communication passage G does not occur, the pump efficiency is lowered. In this regard, according to the present embodiment, at least a part of the cleaning water that is about to flow from the first discharge port 47 side to the unintended second discharge port 48 side through the gap 51b is transferred from the third discharge port 54. It can be discharged out of the pump housing 38. For this reason, since the quantity of the wash water circulated in the pump housing 38 can be reduced again, the fall of the pump efficiency of the pump P can be suppressed.

  Furthermore, in this case, the cleaning water discharged from the third discharge port 54 to the outside of the pump housing 38 can be effectively used as the cleaning water for cleaning the float 29 of the water level sensor 28, so that it is extremely reasonable. That is, the float 29 can be washed without requiring a separate pump or pipe for washing the float 29 and without reducing the dish washing performance and drainage performance of the dishwasher 11.

  (2) The suction port 45 is provided so that a suction pressure region 46 is formed on the suction port 45 side of the blade member 43 at a position on the axis S that is the rotation center of the blade member 43, and the second discharge port. 48 is provided at a position where a part of the discharge pressure region 50 is formed in a region inside the suction pressure region 46 when viewed from the direction of the axis S, so that the suction pressure region 46 and the discharge pressure region 50 are provided. The close positional relationship. Therefore, when the blade member 43 is rotated in the direction indicated by the arrow A in FIG. 5 and the cleaning water is discharged from the first discharge port 47, the blade member 43 flows to the unintended second discharge port 48 side through the gap 51b. Since the cleaning water to be discharged can be promptly guided to the suction pressure region 46 side, the discharge of the cleaning water from the second discharge port 48 can be effectively suppressed.

(Second Embodiment)
Hereinafter, the second embodiment of the present invention will be described focusing on differences from the first embodiment.
In the second embodiment, as shown in FIGS. 8 and 9, the suction pressure region 46 (blade member 43) and the base end portion of the third discharge port 54 in the pump housing 38 of the first embodiment are arranged in the direction of the axis S. An overlapping portion 54a which is an overlapping portion is provided. And in this 2nd Embodiment, the 3rd discharge port 54 is arrange | positioned in the position shifted | deviated to the suction port 45 side with respect to the suction pressure area | region 46 (blade member 43) in the axis line S direction. The overlapping portion 54a constitutes a part of the third discharge port 54 and has a groove portion 54b that opens to the suction pressure region 46 side.

  When the blade member 43 is rotated in the direction indicated by the arrow A or B in FIG. 8 by driving the pump P, the cleaning water flows through the gap 51b toward the second discharge port 48 or the first discharge port 47. A part of the cleaning water flowing through the gap 51b is discharged out of the pump housing 38 from the third discharge port 54 (groove 54b). At this time, since the overlapping portion 54a of the third discharge port 54 overlaps the suction pressure region 46 (blade member 43) in the axis S direction, the third discharge port 54 (groove portion 54b) from the gap 51b as compared with the first embodiment. ) It becomes difficult for washing water to flow into. Accordingly, the amount of cleaning water discharged from the third discharge port 54 to the outside of the pump housing 38 is smaller than that in the first embodiment.

According to the second embodiment described in detail above, in addition to the effects (1) and (2), the following effects are exhibited.
(3) Since the overlapping portion 54 a of the third discharge port 54 overlaps the suction pressure region 46 (blade member 43) in the axis S direction, the washing water flowing through the gap 51 b is difficult to flow into the third discharge port 54. For this reason, the amount of cleaning water discharged from the third discharge port 54 to the outside of the pump housing 38 can be reduced as compared with the case of the first embodiment. Therefore, the configuration of the pump housing 38 in the second embodiment is effective as a countermeasure when the cleaning water is excessively discharged from the third discharge port 54.

  In addition, if the internal diameter of the 3rd discharge port 54 is made small and the discharge amount of the washing water from the 3rd discharge port 54 is reduced, the 3rd discharge port 54 will become easy to be clogged with foreign materials, such as the leftovers contained in the washing water. Although there is a possibility, according to this embodiment, there is almost no such fear. That is, in the present embodiment, the flow rate of the cleaning water discharged from the third discharge port 54 can be suppressed while sufficiently securing the flow path cross-sectional area of the third discharge port 54. Therefore, even if the cleaning water discharged from the third discharge port 54 is used as a cleaning fluid for cleaning the float 29, it adversely affects the float 29 or the amount of cleaning water in the cleaning water tank 27 becomes excessive. There is no overflow. That is, the foreign matter adhering to the float 29 can be quickly washed out while preventing the washing water from overflowing from the washing water tank 27, so that the accuracy of the water level sensor 28 can be maintained.

  Incidentally, if the cleaning water is excessively discharged from the third discharge port 54, the float 29 is adversely affected or the cleaning water overflows from the cleaning water tank 27, so that the accuracy of the water level sensor 28 cannot be maintained. End up.

(Example of change)
In addition, you may change each said embodiment as follows.
As shown in FIGS. 10 and 11, in the second embodiment, the discharge in which the side surface on the second discharge port 48 side in the groove portion 54b of the overlapping portion 54a of the third discharge port 54 is inclined toward the bottom portion of the groove portion 54b. A taper surface 54c as a quantity difference forming portion may be used. In this way, the action of the tapered surface 54c allows the cleaning water to flow from the second discharge port 48 side to the second discharge port 48 side compared to when the cleaning water flows through the gap 51b from the first discharge port 47 side to the second discharge port 48 side. When flowing toward the first discharge port 47 side, the cleaning water easily flows into the third discharge port 54 (groove portion 54b) from the gap 51b. Accordingly, when the cleaning water flows through the gap 51b from the first discharge port 47 side toward the second discharge port 48 side, the cleaning water flows from the second discharge port 48 side toward the first discharge port 47 side. However, the amount of cleaning water discharged from the third discharge port 54 to the outside of the pump housing 38 can be increased.

  Similarly, when the side surface on the first discharge port 47 side in the groove portion 54b is a tapered surface 54c, the cleaning water passes through the gap 51b and the second discharge port 48 from the first discharge port 47 side by the action of the tapered surface 54c. The amount of cleaning water discharged from the third discharge port 54 to the outside of the pump housing 38 is greater when flowing from the second discharge port 48 side toward the first discharge port 47 side than when flowing toward the side. Can be reduced.

  Thus, the cleaning water forms the gap 51b and the first discharge port 47 by setting one of the side surface on the first discharge port 47 side and the side surface on the second discharge port 48 side in the groove portion 54b to the tapered surface 54c. When flowing from the side toward the second discharge port 48 (when the blade member 43 rotates in the direction indicated by the arrow A in FIG. 10), when flowing from the second discharge port 48 side toward the first discharge port 47 side. (The time when the blade member 43 rotates in the direction indicated by the arrow B in FIG. 10), the amount of cleaning water discharged from the third discharge port 54 to the outside of the pump housing 38 can be made different.

  -As shown in FIG.12 and FIG.13, you may use the pump P as a pump for supplying the water stored by the container T, for example to the mist sauna apparatus (not shown). In this case, one end side of the water supply pipe (not shown) connected to the mist sauna device is connected to the first discharge port 47, and one end side of the second discharge port 48 is connected to the drain port (not shown). The other end of the drain pipe (not shown) is connected. Furthermore, in this case, since the pump P is installed in the container T in which water is stored so that only the pump portion 36 is immersed in water, the third discharge port 54 may be configured by a simple through hole instead of a cylindrical shape. .

  In each of the above embodiments, the cleaning water discharged from the third discharge port 54 to the outside of the pump housing 38 may be supplied to the storage tank 23 or may be discharged to the outside of the machine body 12. Good.

  In each of the above embodiments, two or more third discharge ports 54 may be provided in the pump housing 38. In this way, the wash water discharged from each third discharge port 54 can be effectively used simultaneously for different purposes.

  In each of the above embodiments, the pump P is embodied as a reversible pump without a switching valve provided with a communication path G, but may be embodied as a reversible pump with a switching valve. That is, when the blade member 43 rotates in one of the forward and reverse directions (the direction indicated by the arrow A in FIG. 5), the first discharge port 47 is opened and the second discharge port 48 is closed, and the blade member 43 is closed. Is provided in the pump housing 38 for closing the first discharge port 47 and opening the second discharge port 48 when it rotates in the other direction (the direction indicated by arrow B in FIG. 5) of both the forward and reverse directions. May be.

  In each of the above embodiments, the pump P is embodied as a pump for the dishwasher 11, but may be embodied as a pump mounted on an arbitrary device or the like. In this case, the fluid flowing into the pump may be any liquid (for example, alcohol) or gas (for example, air) other than water (washing water).

Further, technical ideas that can be grasped from the above embodiments will be described below.
(A) A blade member that is rotatable in both forward and reverse directions around a predetermined axis is accommodated in the pump housing,
In the pump housing,
A suction port for sucking fluid into the pump housing from the outside of the pump housing based on the rotation of the blade member;
A fluid passage for causing the fluid sucked into the pump housing from the suction port to flow in the same direction as the rotation direction of the blade member;
A first discharge port for discharging fluid from the fluid passage to the outside of the pump housing when the blade member rotates in one of the forward and reverse directions;
A second discharge port for discharging fluid from the fluid passage to the outside of the pump housing when the blade member rotates in the other of the forward and reverse directions;
A communication path communicating between at least one of the discharge pressure regions formed in the vicinity of the first discharge port and in the vicinity of the second discharge port and a suction pressure region formed in the vicinity of the suction port; In the pump provided with
In a position between the first discharge port and the second discharge port along the rotation direction of the blade member in the pump housing, a third discharge for discharging fluid from the fluid passage to the outside of the pump housing. A pump characterized in that an outlet is provided.

  Conventionally, for example, a pump as disclosed in Japanese Patent Application Laid-Open No. 2005-307787 is known as a pump that is mounted on a dishwasher and used when washing dishes or draining sewage after washing. This pump includes a pump housing, and a vane member that can rotate in both forward and reverse directions based on rotational driving of a motor is provided in the pump housing. Further, the pump housing has a suction port for sucking washing water into the pump housing, and a first discharge for supplying the washing water in the pump housing sucked from the suction port to the washing chamber side of the dishwasher. An outlet and a second discharge port for discharging the wash water in the pump housing sucked from the suction port to the outside of the dishwasher are formed.

  When the blade member rotates in one direction (for example, the positive direction) to wash the tableware, the washing water sucked into the pump housing is rotated along the peripheral wall portion in the pump housing. Is discharged from the first discharge port by flowing through the fluid passage in the same direction (positive direction). On the other hand, when the blade member rotates in the other direction (for example, the reverse direction) to discharge the cleaning water, the cleaning water sucked into the pump housing rotates along the peripheral wall portion in the pump housing. The fluid is discharged from the second discharge port by flowing in the fluid passage in the same direction (reverse direction) as the direction.

  Further, in the pump described in Japanese Patent Laid-Open No. 2005-307787, the first discharge port and the second discharge port are provided between the first discharge port and the second discharge port in the pump housing. It communicates via a gap (which constitutes part of the fluid passage) between the blade member (which constitutes a part of the peripheral wall in the pump housing) and the blade member. For this reason, for example, when the blade member is rotated in the forward direction to discharge the cleaning water from the first discharge port, a part of the cleaning water passes from the first discharge port side to the unintended second discharge port side through the gap. In order to suppress the flow, a groove portion constituting a part of the fluid passage is formed in a passage portion communicating with the second discharge port in the pump housing in order to suppress this.

  As described above, the pump described in Japanese Patent Application Laid-Open No. 2005-307787 is configured to change the rotation direction of the blade member so that the washing water sucked into the pump housing is discharged to the first discharge port without the need for a switching valve. And it is possible to selectively discharge from any one of the second discharge ports.

  By the way, the pump described in Japanese Patent Application Laid-Open No. 2005-307787 is formed by forming a portion where no pressure is generated in the middle of the groove due to the action of the groove when, for example, the cleaning water is discharged from the first discharge port. There is a problem in that the pump efficiency is lowered because the cleaning water that attempts to flow from the one discharge port side to the unintended second discharge port side through the gap is circulated in the pump housing again.

  That is, normally, when the fluid is sucked from the suction port and discharged from the first discharge port or the second discharge port, the suction pressure region becomes negative pressure and each discharge pressure region becomes positive pressure. The fluid suction pressure (negative pressure) and discharge pressure (positive pressure) cancel each other to form a portion where no pressure is generated. For this reason, for example, when the blade member is rotated in one direction to discharge the fluid from the first discharge port, the fluid that tends to flow from the first discharge port side to the unintended second discharge port side has this pressure. Since it is circulated in the pump housing again by the portion that does not occur, the pump efficiency is lowered.

  In this regard, according to the technical idea described in (a) above, at least a part of the fluid that is about to flow from the first discharge port side to the unintended second discharge port side is discharged from the third discharge port to the pump housing. It is discharged outside. For this reason, since the quantity of the fluid circulated in the pump housing decreases again, it becomes possible to suppress a decrease in pump efficiency.

The schematic sectional drawing of the dishwasher in 1st Embodiment. The partial sectional view of the pump of the dishwasher. The top view of the pump housing of the pump. The side view of the pump housing of the pump. FIG. 5 is a partial cross-sectional view taken along line 5-5 in FIG. FIG. 6 is a cross-sectional view taken along line 6-6 in FIG. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. The top view of the pump housing in 2nd Embodiment. FIG. 9 is a cross-sectional view taken along line 9-9 in FIG. 8. The top view of the pump housing of the example of a change. FIG. 11 is a cross-sectional view taken along line 11-11 in FIG. 10. The side view of the pump of the example of a change. The top view of the pump housing of the pump.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 11 ... Dishwasher as a washing machine, 28 ... Water level sensor as fluid amount sensor, 38 ... Pump housing, 43 ... Blade member, 45 ... Suction port, 46 ... Suction pressure area, 47 ... First discharge port, 48 ... First 2 discharge ports, 49, 50 ... discharge pressure region, 51 ... fluid passage, 51a ... passage portion, 54 ... third discharge port, 54a ... overlapping portion, 54c ... tapered surface as discharge amount difference forming portion, G ... communication passage , P ... pump, S ... axis.

Claims (4)

A blade member that is rotatable in both forward and reverse directions around a predetermined axis is accommodated in the pump housing,
In the pump housing,
A suction port for sucking fluid into the pump housing from the outside of the pump housing based on the rotation of the blade member;
A fluid passage for causing the fluid sucked into the pump housing from the suction port to flow in the same direction as the rotation direction of the blade member;
A first discharge port for discharging fluid from the fluid passage to the outside of the pump housing when the blade member rotates in one of the forward and reverse directions;
A second discharge port for discharging fluid from the fluid passage to the outside of the pump housing when the blade member rotates in the other of the forward and reverse directions;
In the pump provided with a third discharge port for discharging the fluid from the fluid passage to the outside of the pump housing when the blade member rotates in at least one of the forward and reverse directions,
When the blade member rotates in at least one of the forward and reverse directions, a negative pressure region formed near the suction port is a suction pressure region.
The pump, wherein the third discharge port has an overlapping portion that is a portion that overlaps the suction pressure region in the axial direction that is the rotation center of the blade member. The overlapping portion includes a discharge amount of the fluid discharged from the third discharge port when the blade member rotates in one of the forward and reverse directions, and the other of the forward and reverse directions of the blade member. The discharge amount difference forming part for making a difference between the discharge amount of the fluid discharged from the third discharge port when rotating in the direction is provided. pump. Providing a communication path that communicates between at least one discharge pressure region and the suction pressure region among the discharge pressure regions formed in the vicinity of the first discharge port and in the vicinity of the second discharge port;
3. The third discharge port is provided at a position between the first discharge port and the second discharge port along the rotation direction of the blade member in the pump housing. The pump described. It is mounted on a washing machine having a fluid amount sensor for detecting the fluid amount inside,
The pump according to any one of claims 1 to 3, wherein the fluid discharged from the third discharge port is used as a cleaning fluid for cleaning the fluid amount sensor. .

Images