JP5166965B2 - Fluid pump - Google Patents

Description

  The present invention relates to a fluid pump in which a rotary blade rotates by driving a motor to pump fluid.

  The fluid pump described in Patent Document 1 describes a rotor blade that pumps fluid in a pump chamber by rotating. The rotor blades are fixed to a motor output shaft that extends from the motor chamber including the motor through the communication path into the pump chamber.

Here, the communication passage is provided with an oil seal so that the fluid in the pump chamber does not flow into the motor chamber. Furthermore, a labyrinth structure is provided on the radially outer side of the oil seal in the pump chamber to suppress the flow velocity and fluid pressure of the fluid flowing in the vicinity of the oil seal. Thereby, the fluid is prevented from leaking to the motor chamber by reducing the fluid pressure of the fluid flowing in the vicinity of the oil seal (seal member).
Japanese Patent Laid-Open No. 10-274195

  However, the fluid may stay in the vicinity of the seal member by suppressing the flow velocity and flow pressure of the fluid flowing in the vicinity of the seal member. When the fluid stays in the vicinity of the seal member, the precipitate deposited from the fluid bites into the seal portion of the seal member, and when the motor output shaft is rotated in this state and the seal member and the motor output shaft are slid, the seal It is conceivable that abnormal wear occurs in the seal portion of the member and the sealing function of the seal member is lowered.

  In view of the above fact, it is an object of the present invention to suppress a decrease in the sealing function of the sealing member.

A fluid pump according to a first aspect of the present invention is provided adjacent to the motor chamber that houses a motor, the motor chamber, and communicates with the motor chamber through a communication path, and through the communication path, the motor. A pump chamber in which the output shaft member of the motor extending from the chamber is disposed, a seal member provided in the communication path and sealing the communication path and the output shaft member, and a gap between the seal member and the seal member. is fixed to the output shaft member, said side seal member is disposed, and a rotor blade having an opening formed for communicating the pump chamber side, an opening portion formed in the rotor blades plurality The partition plates that are individually formed and partition the plurality of openings have a blade shape that allows fluid to flow from the seal member side to the pump chamber side.

  According to the above configuration, the output shaft member of the motor extending from the motor chamber through the communication path is arranged in the pump chamber into which the fluid flows, and the output shaft member is rotated to pump the fluid in the pump chamber. Wings can be fixed. A seal member is provided in the communication path to prevent fluid from flowing from the pump chamber to the motor chamber.

  Here, the rotor blade provided with a gap from the seal member is formed with an opening that communicates the side where the seal member is disposed and the pump chamber side.

  Thereby, the fluid which flows into the clearance gap between a rotary blade and a sealing member flows through the opening part to the pump chamber side. For this reason, the fluid pressure of the fluid which presses a sealing member can be suppressed.

  In addition, since the fluid does not stay in the vicinity of the seal member, it is possible to reduce abnormal wear of the seal member by suppressing the deposit deposited from the fluid from adhering to the sliding portion of the seal member, thereby reducing the seal member. The deterioration of the sealing function can be suppressed.

Further, a plurality of openings formed in the rotor blades are formed, and the partition plate that partitions the plurality of openings has a blade shape that allows fluid to flow from the seal member side to the pump chamber side. For this reason, since the fluid that has flowed from the outside in the radial direction into the gap between the rotor blade and the seal member is more effectively flowed to the pump chamber side, the fluid does not stay in the vicinity of the seal member, and is thus deposited from the fluid. It can suppress more effectively that a deposit adheres to the sliding part of a seal member.

A fluid pump according to a second aspect of the present invention is the fluid pump according to the first aspect, characterized in that a labyrinth portion for reducing the flow velocity of the fluid is formed on the radially outer side of the seal member.

  According to the said structure, the labyrinth part is provided in the radial direction outer side of the sealing member. As the fluid flows through the labyrinth portion, the flow velocity of the fluid decreases in the labyrinth portion, and foreign matter (cast sand, etc.) contained in the fluid is captured by the labyrinth portion, thereby suppressing foreign matter from adhering to the seal member. be able to.

  An example of the fluid pump according to the first embodiment of the present invention will be described with reference to FIGS.

(overall structure)
As FIG. 5 shows, the water pump 10 as a fluid pump based on this invention is used suitably as an electric water pump for engine cooling devices of a motor vehicle, for example.

  The water pump 10 includes a motor unit 12 and a pump unit 14. The motor unit 12 includes a substantially cylindrical motor housing 16 with a bottom, and a sub housing 20 that is adjacent to the motor housing 16 and is fixed to an opening of the motor housing 16.

  By connecting and fixing the motor housing 16 and the sub-housing 20, a motor chamber 18 in which a motor 22 serving as a drive source is accommodated is formed.

  Further, the output shaft member 24 of the motor 22 is formed in a stepped columnar shape, and a communication path 26 for inserting the output shaft member 24 is formed in the axial center portion of the top wall 20A of the sub housing 20. Yes. Furthermore, a bearing member 15 that rotatably supports the output shaft member 24 is provided on the top wall 20A.

  An end plate 28 that holds the motor 22 is attached to the open end of the motor housing 16.

  On the other hand, the pump portion 14 includes a pump housing 30 that is fitted and fixed to the end portion 20B of the sub housing 2 (the end portion on the distal end side of the output shaft member 24). The pump housing 30 is provided with a discharge port 28 provided along a crossing direction intersecting the output shaft member 24 and a suction port 38 provided so as to bend in the axial direction of the output shaft member 24. Both are communicated with a pump chamber 36 formed inside the pump housing 30.

  The pump housing 30 is provided with an open portion 30B that opens the pump chamber 36. When the open portion 30B of the pump housing 30 is assembled to the end portion 20B of the sub housing 20, the end portion of the sub housing 20 is provided. The O-ring 32 fitted to the outer peripheral surface of 20B seals between the outer peripheral surface of the end portion 20B and the inner peripheral surface of the open portion 30B of the pump housing 30.

  Further, an impeller 40 as a rotary blade is rotatably fixed to the output shaft member 24 and accommodated in the pump chamber 36. A recess 34 is formed at the end 20B of the sub housing 20 facing the impeller 40 so as to surround the output shaft member 24. The recess 34 has an inner peripheral surface of the communication passage 26 and the output shaft member 24. A seal member 42 is provided to be spaced from the impeller 40.

(Main part)
Next, the seal member 42 and the impeller 40 will be described.

  As shown in FIG. 1 and FIG. 2 (A), it is formed in an annular shape so as to surround the seal member 42 and the output shaft member 24 disposed in the recess 34. Specifically, the L-shaped panel member 42A for retaining the shape is covered with a rubber material so as to form a substantially U-shaped cross section.

  A trapezoidal compression portion 42B is formed at a portion of the seal member 42 facing the vertical wall 34A of the recess 34. When the seal member 42 is attached to the recess 34, the compression portion 42B is connected to the vertical wall 34A and the panel member 42A. So as to be in close contact with the vertical wall 34A.

  On the other hand, a portion of the seal member 42 that faces the output shaft member 24 is provided with a lip sliding portion 42 </ b> C that is formed in a convex shape toward the output shaft member 24. When the output shaft member 24 is inserted through the seal member 42, the lip sliding portion 42C is brought into close contact with the output shaft member 24 while falling down radially outward. With this configuration, when the output shaft member 24 rotates, the output shaft member 24 slides between the output shaft member 24 and the lip sliding portion 42C.

  An impeller 40 that is fixed to the output shaft member 24 with a gap 58 is disposed on the pump chamber 36 side (the front end side of the output shaft member 24) of the seal member 42.

  As shown in FIGS. 1 and 3, the impeller 40 includes a disc-shaped bottom flat plate portion 43 that is disposed on the seal member 42 side and is disposed with a predetermined gap from the wall surface of the sub-housing 20. A cylindrical shaft center portion 46 extending to the pump chamber 36 side is fixed to the center portion of the bottom flat plate portion 43.

  Further, on the pump chamber 36 side of the bottom flat plate portion 43, a plurality of blade members 44 that send the fluid flowing in from the suction port 38 toward the discharge port 28 are provided at equal intervals around the shaft center portion 46. Yes. Further, around the shaft center portion 46, four openings 50 partitioned by a partition plate 48 are provided so as to communicate the seal member 42 side and the pump chamber 36 side.

  The blade member 44 is fixed to the output shaft member 24 by fitting the distal end side of the output shaft member 24 into the shaft center portion 46.

  Further, as shown in FIG. 1, an annular projecting piece 52 having an annular cylindrical shape is provided on the side of the sub-housing 20 in the bottom flat plate portion 43 so as to surround the seal member 42. A concave annular recess 54 is formed in the sub-housing 20 so as to accommodate the annular projecting piece 52 so as to accommodate the portion 52. In this way, the labyrinth portion 56 in which the flow path is bent like a maze is provided around the annular projecting piece portion 52.

(Action / Effect)
Here, this inventor analyzed the flow of the fluid in the pump chamber 36 of the water pump 10 by FEM.

  FIG. 4 shows the flow of fluid in the pump chamber 36 when the motor 22 (see FIG. 5) is driven and the output shaft member 24 is rotated to rotate the impeller 40. The fluid flows in the direction of the arrow, and the higher the density of the arrow, the faster the fluid flow velocity at that part.

  The vicinity of the radially outer end of the impeller 40 (A portion in the figure) is a fluid flow path that flows from the suction port 38 toward the discharge port 28 (see FIG. 5) and has a positive pressure. On the other hand, the front end side (B portion in the figure) of the output shaft member 24 on the shaft center side of the impeller 40 becomes a negative pressure when the blade member 44 of the impeller 40 rotates.

  In this way, the portion A in the figure has a positive pressure and the portion B in the figure has a negative pressure, whereby the gap 58 provided between the bottom flat plate portion 43 and the sub-housing 20 is directed from the radially outer side to the inner side. A fluid flow occurs.

  Specifically, the fluid that has flowed into the gap from the outside in the radial direction collides with the annular projecting piece 52 and flows toward the bottom 56 </ b> A of the labyrinth 56. The fluid that has reached the bottom portion 56A swirls in a U shape and flows toward the bottom flat plate portion 43, and the fluid that has reached the bottom flat plate portion 43 flows radially inward. Furthermore, the fluid that has flowed into the center of the shaft flows through the opening 50 provided in the impeller 40 and flows into the pump chamber 36 side.

  Further, the inventor of the present application also analyzed the conventional structure in which the opening 50 is not provided in the impeller 40 by FEM as a comparative example of the present invention.

  As shown in FIG. 6, the impeller 100 having the conventional structure is not provided with the opening 50 that communicates the seal member 42 side and the pump chamber 36 side.

  As shown in FIG. 7, the fluid that has flowed into the gap between the impeller 100 and the sub-housing 20 from the outside in the radial direction collides with the annular projecting piece portion 52 and flows toward the bottom portion 56 </ b> A of the labyrinth portion 56. However, the fluid reaching the bottom 56A does not flow to the shaft center side because the impeller 100 is not provided with an opening that connects the seal member 42 side and the pump chamber 36 side. Thereby, the fluid in the vicinity of the seal member 42 stays on the spot.

  Here, the inventor of the present application evaluated the influence on the seal member 42 when the fluid stayed in the vicinity of the seal member 42 through experiments.

  As the fluid, a long life coolant liquid (LLC) used for automobile engine coolant was used. A water pump having a conventional structure in which no opening was provided in the impeller was actually driven, and after the drive, the seal member 42 was removed from the water pump, and the shape of the lip sliding portion 42C of the seal member 42 was confirmed.

  2B indicates the shape of the lip sliding portion 42C in the initial state, and the solid line indicates the shape after evaluation. As can be seen, it can be seen that streak wear occurs in the lip sliding portion 42C formed of a rubber material, and the tip portion is scraped off. This is because the long-life coolant liquid stays, the rust inhibitor component (phosphate) contained in the long-life coolant liquid precipitates, and is caught between the lip sliding portion 42C and the output shaft member 24, This is because the tip of the lip sliding portion 42C has been scraped off by sliding the lip sliding portion 42C. That is, in the conventional structure, the long life coolant liquid stays in the vicinity of the seal member 42, and the tip end portion of the lip sliding portion 42C is scraped off, resulting in a decrease in the sealing function.

  As described above, in the present invention, by providing the opening 50 in the impeller 40, the fluid that has flowed into the gap 58 from the radially outer side is caused to flow into the pump chamber 36, so that the fluid stays in the vicinity of the seal member 42. Can be suppressed. In this way, by suppressing the retention of the fluid, it is possible to prevent the deposit deposited from the fluid from being caught in the seal member 42 and scraping off the lip sliding portion 42C of the seal member 42.

  Further, by preventing the lip sliding portion 42C from being scraped off, it is possible to suppress the deterioration of the sealing function of the sealing member 42.

  Further, as shown in FIG. 4, a labyrinth portion 56 is provided, and a fluid is swung in a U-shape in the vicinity of the bottom portion 56A of the labyrinth portion 56, so that foreign matter (such as cast sand) having a high specific gravity is removed from the bottom portion 56A. Can be deposited.

  In addition, since the opening 50 is only formed in the impeller 40 as compared with the prior art, the reduction in the sealing function of the seal member 42 can be suppressed while reducing the weight without increasing the manufacturing cost. it can.

  Next, 2nd Embodiment of the water pump 80 of this invention is described according to FIG. 8, FIG.

  In addition, about the same member as 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted.

  As shown in FIGS. 8A and 8B, in this embodiment, unlike the first embodiment, the partition plate 74 that partitions the opening 72 provided in the impeller 70 is provided on the pump chamber 36 from the seal member 42 side. It is made into a blade | wing shape so that a fluid may be flowed to the side.

  As shown in FIG. 9, by making the partition plate 74 into a blade shape, the fluid that has flowed from the radially outer side to the gap 58 between the impeller 70 and the seal member 42 is more effectively flowed toward the pump chamber 36 side. This prevents the fluid from staying in the vicinity of the seal member 42. Thereby, it can prevent more effectively that the deposit deposited from the fluid adheres to the lip sliding portion 42C of the seal member 42.

  Moreover, the fall of the sealing function of the sealing member 42 can be suppressed by preventing that a deposit adheres to 42 C of lip | sliding parts.

  In addition, by forming the partition plate 74 into a blade shape and actively flowing the fluid in the vicinity of the seal member 42 toward the pump chamber 36, as shown in FIG. Etc.) can be discharged to the pump chamber 36 through the opening 72.

It is an expanded sectional view showing the water pump concerning a 1st embodiment of the present invention. (A) (B) It is sectional drawing which showed the sealing member employ | adopted as the water pump which concerns on 1st Embodiment of this invention. It is the top view which showed the impeller employ | adopted as the water pump which concerns on 1st Embodiment of this invention. It is drawing which represented the result of having analyzed by the FEM about the water pump which concerns on 1st Embodiment of this invention. It is the whole sectional view showing the water pump concerning a 1st embodiment of the present invention. It is the top view which showed the impeller employ | adopted as the conventional water pump analyzed as a comparative example of the water pump which concerns on 1st Embodiment of this invention. It is drawing which represented the result of having analyzed by the FEM about the conventional water pump as a comparative example of the water pump which concerns on 1st Embodiment of this invention. (A) (B) It is the top view and cross-sectional perspective view which showed the impeller employ | adopted as the water pump which concerns on 2nd Embodiment of this invention. It is drawing which represented the result of having analyzed by the FEM about the water pump which concerns on 2nd Embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Water pump (fluid pump), 18 ... Motor chamber, 22 ... Motor, 24 ... Output shaft member, 26 ... Communication path, 36 ... Pump chamber, 40 ... Impeller (rotary blade), 42 ... seal member, 48 ... partition plate, 50 ... opening, 56 ... labyrinth, 70 ... impeller (rotary blade), 72 ... opening 74 ... partition plate

Claims (2)

A motor chamber that houses the motor;
A pump chamber provided adjacent to the motor chamber, communicated with the motor chamber through a communication path, and disposed with an output shaft member of the motor extending from the motor chamber through the communication path;
A seal member provided in the communication path and sealing the communication path and the output shaft member;
A rotary blade fixed to the output shaft member with a gap from the seal member, and formed with an opening that communicates the side on which the seal member is disposed and the pump chamber side ;
A fluid pump in which a plurality of openings formed in the rotor blade are formed, and a partition plate that partitions the plurality of openings is a blade shape that allows fluid to flow from the seal member side to the pump chamber side.   The fluid pump according to claim 1, wherein a labyrinth portion that reduces a fluid flow rate is formed on a radially outer side of the seal member.

Images