Stirring blade and washing machine

Abstract

A stirring blade capable of stirring a fluid by rotating about a rotating shaft, the stirring blade comprising: a blade body protruding in the axial direction from one surface of the stirring blade and extending from the inside in the radial direction to the outside in the radial direction of the rotating shaft; and a first facing surface facing the blade body in the circumferential direction of the stirring blade, the first facing surface having a smaller inclination angle on the radially outer side than on the radially inner side.

Description

Technical Field

[0001] This disclosure relates to an agitator blade and a washing machine. Background Technology

[0002] Washing machines equipped with agitator blades are known in the past. For example, in the washing machine disclosed in Patent Document 1, the agitator blades are rotatably disposed at the bottom of the agitator tub. During washing, water is stored in the agitator tub containing the laundry, and the laundry is washed by agitating the water as a fluid through the rotation of the agitator blades.

[0003] Existing technical documents Patent documents Patent Document 1: Japanese Patent No. 5184678 Summary of the Invention The technical problem that the invention aims to solve The agitator blades are intended to improve the washing effect of detergents washed in the agitator.

[0004] One objective of this disclosure is to provide agitator blades and a washing machine that can improve the washing effect of laundry washed in an agitator tub. Furthermore, one aspect of this disclosure is related to biomimicry because it incorporates a technical concept inspired by the tail fin of a dolphin.

[0005] Solution to the problem One aspect of this disclosure is a stirring blade capable of agitating a fluid by rotation about a rotation axis, comprising: a blade body projecting axially from one face of the stirring blade and extending radially outward from the radially inner side of the rotation axis; and a first opposing surface opposing the blade body in the circumferential direction of the stirring blade, the first opposing surface having a smaller inclination angle on the radially outer side than on the radially inner side.

[0006] One aspect of this disclosure is a washing machine equipped with the aforementioned agitator blades. Attached Figure Description

[0007] Figure 1 This is a front sectional view showing the general structure of the washing machine.

[0008] Figure 2 This is a three-dimensional view of the stirring blades when viewed from an oblique angle above.

[0009] Figure 3 This is a top view of the stirring blades.

[0010] Figure 4 This is a magnified view of roughly half of the stirring blades when viewed from above.

[0011] Figure 5 It is along Figure 4A cross-sectional view of line II in the direction of view.

[0012] Figure 6 It is along Figure 4 A cross-sectional view of the line II-II in the direction of view.

[0013] Figure 7 It is along Figure 4 A cross-sectional view of line III-III in the direction of view.

[0014] Figure 8 It is along Figure 4 A cross-sectional view of the IV-IV line in the direction of view.

[0015] Figure 9 This is a three-dimensional view of the stirring blades when viewed from a slightly downward angle.

[0016] Figure 10 This is a bottom view of the stirring blades.

[0017] Figure 11 It is along Figure 10 A cross-sectional view of the VV line in the direction of view.

[0018] Figure 12A This is a schematic longitudinal sectional view of a washing machine in operation.

[0019] Figure 12B This is a schematic longitudinal sectional view of a washing machine in operation.

[0020] Figure 12C This is a schematic longitudinal sectional view of a washing machine in operation.

[0021] Figure 12D This is a schematic longitudinal sectional view of a washing machine in operation.

[0022] Figure 12E This is a schematic longitudinal sectional view of a washing machine in operation.

[0023] Figure 12F This is a schematic longitudinal sectional view of a washing machine in operation.

[0024] Figure 13A It is a schematic side view showing an enlarged portion of the upper surface of the agitator blades containing the washings.

[0025] Figure 13B It is a schematic side view showing an enlarged portion of the upper surface of the agitator blades containing the washings.

[0026] Figure 13C It is a schematic side view showing an enlarged portion of the upper surface of the agitator blades containing the washings.

[0027] Figure 14This is a schematic top view of the upper surface of the agitator blades equipped with the washing material.

[0028] Figure 15A It is a schematic longitudinal section view of the first recess containing the laundry.

[0029] Figure 15B It is a schematic longitudinal section view of the second recess containing the laundry.

[0030] Figure 16 It is a schematic side view showing an enlarged portion of the upper surface of the agitator blades containing the washings.

[0031] Figure 17 It is a schematic bottom view showing an enlarged portion of the lower surface of the stirring blade.

[0032] Figure 18 It is a schematic bottom view showing an enlarged portion of the lower surface of the stirring blade. Detailed Implementation

[0033] Hereinafter, embodiments of the present disclosure will be described with reference to the accompanying drawings. Furthermore, in the accompanying drawings, the same or equivalent elements will be labeled with the same reference numerals, and repeated descriptions will be omitted.

[0034] [washing machine] Figure 1 This is a front sectional view showing the general structure of washing machine 1. In the following description, Figure 1 The top, bottom, left, right, front side of the paper, and inside the paper are defined as the top, bottom, left, right, front, and rear sides of the washing machine 1.

[0035] The washing machine 1 of this embodiment is a vertical washing machine having a rectangular outer casing 10 that is longer in the vertical direction. A top panel 11 with an operation panel and the like is fixed to an opening on the upper surface of the outer casing 10. A base 12 with multiple feet 13 is fixed to an opening on the bottom surface of the outer casing 10. An inlet 14 for taking out and putting in laundry into the agitator 30 and a top cover 15 for opening and closing the inlet 14 are provided on the top panel 11.

[0036] Inside the outer casing 10 are a mixing tank 30 and a water tank 20 for housing the mixing tank 30. The mixing tank 30 stores water containing dissolved detergent or rinsing water. Both the water tank 20 and the mixing tank 30 are bottomed cylindrical vessels with open surfaces, extending vertically in a manner that is approximately aligned with their axes. The mixing tank 30 has a bottom wall 30A and a peripheral wall 30B. The peripheral wall 30B is a cylindrical vessel that extends upwards in a conical shape from the bottom wall 30A. The lower end of the peripheral wall 30B is a curved surface that is continuous with the periphery of the bottom wall 30A. A plurality of dewatering holes 31 arranged in a ring are provided at the upper edge of the peripheral wall 30B.

[0037] An annular balancer 32 for suppressing vibrations during dehydration is installed around the periphery of the upper opening of the mixing tank 30. An agitator 70, capable of stirring the fluid by rotating around a rotation axis O, is disposed on the inner bottom surface of the mixing tank 30. In this example, the rotation axis O extends vertically in a manner substantially aligned with the axes of the water tank 20 and the mixing tank 30. The agitator 70 is disc-shaped around the rotation axis O. A gap 34 is formed between the periphery of the agitator 70 and the peripheral wall 30B.

[0038] A drive unit 40 is provided on the lower side of the water tank 20. The drive unit 40 includes a motor 41, a transmission belt mechanism 42, a clutch and brake mechanism 43, a dehydration shaft 44, and a stirring blade shaft 45. The dehydration shaft 44 and the stirring blade shaft 45 are a double shaft structure with the dehydration shaft 44 located on the outer side and the stirring blade shaft 45 located on the inner side, protruding upward from the drive unit 40. The dehydration shaft 44 extends upward through the bottom surface of the water tank 20 and supports the stirring tank 30. The stirring blade shaft 45 extends upward through the water tank 20, and further through the bottom wall 30A of the stirring tank 30, and supports the stirring blades 70.

[0039] The control unit of the washing machine 1 is located inside the upper panel 11. Based on the instructions input by the user using the operation panel, the control unit controls the drive unit 40, water supply valve, and drain valve to perform washing, rinsing, and spin-drying operations. For example, the agitator blades 70 rotate at 55-300 rpm for washing or rinsing, and rotate together with the agitator tub 30 at 0-1200 rpm for spin-drying.

[0040] [Upper surface structure of the stirring blade] Details of the blade section 100 are explained. Figure 2 This is a three-dimensional view of the stirring blade 70 when viewed from an oblique angle. Figure 3 This is a top view of the stirring blade 70. Figure 4 This is an enlarged view of approximately half of the stirring blades when viewed from above. Figure 5 It is along Figure 4 A cross-sectional view of line II in the direction of view. Figure 6 It is along Figure 4 A cross-sectional view of the line II-II in the direction of view. Figure 7 It is along Figure 4 A cross-sectional view of line III-III in the direction of view. Figure 8 It is along Figure 4 A cross-sectional view of the IV-IV line in the direction of view.

[0041] like Figures 2 to 4As shown, the stirring blade 70 has blade portions 100 protruding from one surface of the stirring blade 70, extending radially inward from the rotation axis O. In this example, a plurality of blade portions 100 protruding upward from the upper surface 71 of the stirring blade 70 are arranged circumferentially along C. The circumferential direction C is parallel to the rotation direction of the stirring blade 70 centered on the rotation axis O. The rotation axis O passes through the central portion of the stirring blade 70 when viewed from above. The area near the radially outer end of the stirring blade 70 is referred to as the outer periphery of the stirring blade 70. The four blade portions 100 are arranged circumferentially along C at approximately 90-degree intervals and extend radially from the area near the central portion of the stirring blade 70 to the outer periphery along the rotation axis O.

[0042] The stirring blade 70 has a blade portion 100 on one surface and adjacent first recesses 110 on the circumferential direction C of the stirring blade 70. In this example, two first recesses 110 are provided on both sides of the upper surface 71 sandwiching the central portion. When viewed from above, each first recess 110 is sandwiched between two adjacent blade portions 100 on the circumferential direction C. That is, each first recess 110 is adjacent to two blade portions 100 on the circumferential direction C.

[0043] The blade portion 100 includes a first side surface 101 extending from the bottom surface 111 of the first recess 110 toward the ridge line R of the blade portion 100. The ridge line R is an imaginary line connecting the two ends of the blade portion 100 in the extending direction and extending along the highest portion of the surface of the blade portion 100. In this example, the bottom surface 111 is a smooth surface that is continuous in the radial direction, so it extends smoothly without any bumps or steps except for the drainage holes. The upper end surface 103 of each blade portion 100 includes a ridge line R extending in the radial direction and has a width extending from the ridge line R to both sides in the circumferential direction C. The first side surface 101 of each blade portion 100 extends from the bottom surface 111 toward the ridge line R and connects with the upper end surface 103.

[0044] like Figures 4 to 6 As shown, the tilt angle θ11 is larger on the radially outer side than on the radially inner side. The tilt angle θ11 is the angle between the first side surface 101 and an imaginary plane V1 orthogonal to the rotation axis O. The imaginary plane V1 is synonymous with a plane extending parallel to the rotation direction of the stirring blade 70. In this example, the imaginary plane V1 is a horizontal plane orthogonal to the vertical direction. The tilt angle θ11 is the size of the angle between the horizontal imaginary plane V1 and the first side surface 101 in a cross-section that cuts the blade portion 100 orthogonal to the extension direction of the blade portion 100, passing through any point on the first side surface 101.

[0045] Figure 5 The example shows a cross section in which the blade portion 100 is cut radially orthogonal through a point located radially inside the first side 101. Figure 6The diagram shows a cross-section of the blade portion 100 cut radially orthogonal to the radial direction, passing through a point located radially outward in the first side surface 101. That is, Figure 5 and Figure 6 The image shows a longitudinal section of the blade portion 100 viewed from the radially outer side, and... Figure 6 Showing the ratio Figure 5 The longitudinal section further outward from the radial direction.

[0046] like Figure 5 and Figure 6 As shown, the first side surface 101 has an upper end portion connected to the upper end surface 103 of the blade portion 100 and a bottom surface 111 connected to the first recess 110 (see reference). Figure 4 The lower end of the first side surface 101 is connected. The tilt angle θ11 is equal to the angle between the imaginary straight line L11 passing through the upper and lower ends of the first side surface 101 and the imaginary plane V1. The imaginary straight line L11 can be a tangent relative to any point of the first side surface 101, for example, it can be a tangent relative to the lower end of the first side surface 101.

[0047] In detail, when the imaginary plane V1 is positioned lower than the blade portion 100, when viewed from the radially outer side, the angle of the region containing the second side surface 102 of the blade portion 100 among the multiple regions divided by the imaginary line L11 and the imaginary plane V1 is the tilt angle θ11. In other words, the tilt angle θ11 represents the slope of the first side surface 101 relative to the horizontal imaginary plane V1; the larger the angle, the steeper the slope of the first side surface 101. The first side surface 101 is tilted such that the tilt angle θ11 continuously increases from the radially inner side to the radially outer side. Therefore, the portion closer to the center of the stirring blade 70 becomes a gentle slope with a small gradient, and the portion closer to the outer periphery of the stirring blade 70 becomes a steep slope with a large gradient.

[0048] like Figures 2 to 4 As shown, the stirring blade 70 has a plurality of blade portions 100, which include first blade portions 100A and second blade portions 100B. In this example, the four blade portions 100 include two first blade portions 100A and two second blade portions 100B. The two first blade portions 100A are disposed on both sides of the central portion sandwiched between the upper surface 71, and have a substantially consistent shape when rotated 180 degrees along the circumferential direction C. The two second blade portions 100B are disposed on both sides of the central portion sandwiched between the upper surface 71, and have a substantially consistent shape when rotated 180 degrees along the circumferential direction C. The adjacent first blade portions 100A and second blade portions 100B are sandwiched by an imaginary vertical plane passing through their respective intermediate positions and are symmetrical.

[0049] The circumferential direction C includes a first direction C1 and a second direction C2 that are opposite to each other. The first side surface 101 of the first blade portion 100A faces the first direction C1. The first side surface 101 of the second blade portion 100B faces the second direction C2. In this example, the first direction C1 is the forward rotation direction of the stirring blade 70, which is clockwise when viewed from above. The second direction C2 is the reverse rotation direction of the stirring blade 70, which is counterclockwise when viewed from above. Therefore, the first side surface 101 of the first blade portion 100A and the first side surface 101 of the second blade portion 100B face opposite directions to each other.

[0050] A first recess 110 is sandwiched between a first blade portion 100A and a second blade portion 100B, and they are adjacent in the circumferential direction C. A first side surface 101 of the first blade portion 100A and a first side surface 101 of the second blade portion 100B both extend from a first recess 110 and are opposite each other in the circumferential direction C. In this example, the first blade portion 100A is adjacent to each of the two first recesses 110 in the second direction C2, and the second blade portion 100B is adjacent to each of the two first recesses 110 in the first direction C1. The first side surface 101 of the first blade portion 100A and the first side surface 101 of the second blade portion 100B both extend from the bottom surface 111 of the same first recess 110. These first side surfaces 101 are opposite each other in the circumferential direction C, separated by the first recess 110.

[0051] like Figure 4 As shown, the ridge line R includes a first ridge line R1 extending radially inward and radially outward, and a second ridge line R2 extending further radially outward from the end of the first ridge line R1. In this example, the ridge line R includes two imaginary points T1 and T2 that roughly trisect the ridge line R. The imaginary point T2 is located radially outward than the imaginary point T1. The first ridge line R1 extends radially outward in a generally straight line from near the center of the stirring blade 70 to the imaginary point T1. The second ridge line R2 extends radially outward from the imaginary point T1 through the imaginary point T2 to the outer periphery of the stirring blade 70.

[0052] In the first blade portion 100A, the second ridge line R2 includes a portion that bends and extends from the first ridge line R1 toward the second direction C2. In this example, in each first blade portion 100A, the second ridge line R2 bends from an imaginary point T1 toward the second direction C2 and extends toward the imaginary point T2, and then extends in a generally straight line from the imaginary point T2 to the outer periphery of the stirring blade 70.

[0053] In the second blade portion 100B, the second ridge line R2 includes a portion that bends and extends from the first ridge line R1 toward the first direction C1. In this example, in each second blade portion 100B, the second ridge line R2 bends from an imaginary point T1 toward the first direction C1 and extends toward an imaginary point T2, and then extends in a generally straight line from the imaginary point T2 to the outer periphery of the stirring blade 70. Thus, in the first blade portion 100A and the second blade portion 100B, the respective second ridge lines R2 bend in opposite directions.

[0054] A second recess 120 is provided on one surface of the stirring blade 70. This second recess 120 is located on the opposite side of the first recess 110, separated from the blade portion 100, and is adjacent to the blade portion 100 in the circumferential direction C. In this example, two second recesses 120 are provided on both sides of the central portion sandwiched between the upper surface 71. The first recess 110 and the second recess 120 are arranged alternately along the circumferential direction C. When viewed from above, each second recess 120 is sandwiched between two adjacent blade portions 100 in the circumferential direction C. That is, each second recess 120 is adjacent to two blade portions 100 in the circumferential direction C.

[0055] like Figures 2 to 4 As shown, the blade portion 100 includes a first side surface 101 extending from the bottom surface 111 of the first recess 110 toward the ridge line R, and a second side surface 102 extending from the bottom surface 121 of the second recess 120 toward the ridge line R. In this example, the bottom surface 121 is a smooth surface that is continuous in the radial direction, and therefore extends smoothly without any bumps or steps except for the drainage holes. The second side surface 102 of each blade portion 100 is disposed on the opposite side of the first side surface 101 across the ridge line R, extends from the bottom surface 121 toward the ridge line R, and connects to the upper end surface 103. The second side surface 102 of the first blade portion 100A faces the second direction C2, and the second side surface 102 of the second blade portion 100B faces the first direction C1. Therefore, the second side surface 102 of the first blade portion 100A and the second side surface 102 of the second blade portion 100B face opposite directions to each other.

[0056] The first side surface 101 includes a first gentle slope 101A and a first steep slope 101B. The first steep slope 101B is located further radially outward than the first gentle slope 101A, and its inclination angle is larger than that of the first gentle slope 101A. In this example, as described above, the inclination angle θ11 of the first side surface 101 is larger radially outward than radially inward. Therefore, when the first side surface 101 is divided into a radially inward and a radially outward slope, the inclination surface on the radially inward side is the first gentle slope 101A (see reference). Figure 5 The radially outer inclined surface is the first steep inclined surface 101B (refer to...). Figure 6 ).

[0057] like Figures 4 to 6As shown, the tilt angle θ12 is smaller on the radially outer side than on the radially inner side. The tilt angle θ12 is the angle between the second side surface 102 and an imaginary plane V1 orthogonal to the rotation axis O. In this example, the tilt angle θ12 is the angle between the horizontal imaginary plane V1 and the second side surface 102 in a cross-section that cuts the blade portion 100 orthogonally to the extending direction of the blade portion 100, passing through any point on the second side surface 102.

[0058] like Figure 5 and Figure 6 As shown, the second side surface 102 has an upper end portion connected to the upper end surface 103 of the blade portion 100 and a bottom surface 121 connected to the second recess 120 (see reference). Figure 4 The lower end of the second side surface 102 is connected. The tilt angle θ12 is equal to the angle between the imaginary straight line L12 passing through the upper and lower ends of the second side surface 102 and the imaginary plane V1. The imaginary straight line L12 can be a tangent at any point on the second side surface 102, or it can be a tangent at, for example, the lower end of the second side surface 102.

[0059] In detail, when the imaginary plane V1 is positioned lower than the blade portion 100, when viewed from the radially outer side, the angle of the region containing the first side surface 101 of the blade portion 100 among the multiple regions divided by the imaginary line L12 and the imaginary plane V1 is the tilt angle θ12. In other words, the tilt angle θ12 represents the slope of the second side surface 102 relative to the horizontal imaginary plane V1; the larger the angle, the steeper the slope of the second side surface 102. The second side surface 102 is tilted in such a way that the tilt angle θ12 continuously decreases from the radially inner side to the radially outer side. The portion closer to the center of the stirring blade 70 becomes a steeper slope, and the portion closer to the outer periphery of the stirring blade 70 becomes a gentler slope.

[0060] The second side surface 102 includes a second steep slope 102B disposed radially inward compared to the second gentle slope 102A. For example, when the second side surface 102 is divided into a radially inward side and a radially outward side, the inclined surface of the radially inward side is the second steep slope 102B (see reference). Figure 5 The radially outer inclined surface is the second gentle slope 102A (refer to...). Figure 6 The inclination angle θ12 of the second steep slope 102B is greater than the inclination angle θ12 of the second gentle slope 102A.

[0061] Furthermore, in each blade section 100, the radial position where the tilt angle θ11 of the first side surface 101 is equal to the tilt angle θ12 of the second side surface 102 is the boundary between the first gentle slope 101A and the first steep slope 101B on the first side surface 101, and the boundary between the second gentle slope 102A and the second steep slope 102B on the second side surface 102. These boundaries can also be configured at an imaginary point T1 connected to the first ridge line R1 and the second ridge line R2 in each blade section 100 (see reference). Figure 4 (At the same radial position.)

[0062] like Figure 4 as well as Figure 6 As shown, the second side surface 102 includes a second gentle slope 102A, which is positioned parallel to the first steep slope 101B in the circumferential direction C. In this example, both the first steep slope 101B of the first side surface 101 and the second gentle slope 102A of the second side surface 102 are located radially outside the stirring blade 70. The first steep slope 101B and the second gentle slope 102A are located on both sides of the ridge line R, and therefore arranged relative to each other in the circumferential direction C. On the radially outer side of each blade portion 100, the inclination angle θ12 of the second gentle slope 102A is smaller than the inclination angle θ11 of the first steep slope 101B.

[0063] like Figure 4 and Figure 5 As shown, the second side surface 102 includes a second steep slope 102B, which is positioned parallel to the first gentle slope 101A in the circumferential direction C. In this example, both the first gentle slope 101A of the first side surface 101 and the second steep slope 102B of the second side surface 102 are located radially inside the stirring blade 70. The first gentle slope 101A and the second steep slope 102B are located on opposite sides of the ridge line R, and therefore arranged relative to each other in the circumferential direction C. In the radially inside of each blade portion 100, the inclination angle θ12 of the second steep slope 102B is larger than the inclination angle θ11 of the first gentle slope 101A.

[0064] like Figures 2 to 4As shown, a plurality of blade portions 100 include a first blade portion 100A and a third blade portion. A second recess 120 is sandwiched between the first blade portion 100A and the third blade portion, and they are adjacent in the circumferential direction C. In this example, the first blade portion 100A is adjacent to each of the two second recesses 120 in the first direction C1, and the second blade portion 100B is adjacent to each of the two second recesses 120 in the second direction C2. The second side surface 102 of the first blade portion 100A and the second side surface 102 of the second blade portion 100B both extend from the bottom surface 121 of the same second recess 120. These second side surfaces 102 are opposite each other in the circumferential direction C, separated by the second recess 120. Therefore, the second blade portion 100B located on the second direction C2 side of the second recess 120 exemplifies the aforementioned third blade portion. Furthermore, the third blade portion can also be a blade portion 100 with a different shape from the second blade portion 100B, as long as it has a second gentle slope 102A.

[0065] The second gentle slope 102A of the first blade portion 100A and the second gentle slope 102A of the third blade portion extend from a second recess 120 and are opposite each other in the circumferential direction C. In this example, the second gentle slope 102A of the first blade portion 100A and the second gentle slope 102A of the second blade portion 100B are both located radially outside the stirring blade 70. In each second recess 120, the second gentle slope 102A of the first blade portion 100A and the second gentle slope 102A of the second blade portion 100B are opposite each other in the circumferential direction C.

[0066] The stirring blade 70 has a protrusion 230 protruding from the second gentle slope 102A and extending in a direction intersecting the circumferential direction C. In this example, a plurality of protrusions 230 are provided on the second gentle slope 102A of each of the four blade portions 100. In other words, a plurality of protrusions 230 are provided on the two second gentle slopes 102A provided on both sides of each second recess 120. In each second gentle slope 102A, a plurality of (three in this example) protrusions 230 are arranged circumferentially C at intervals. Each protrusion 230 extends from the radially inward side toward the radially outward side in a manner intersecting the circumferential direction C.

[0067] Specifically, in the second gentle slope 102A of each first blade portion 100A, each protrusion 230 is an arc shape that bulges slightly towards the first direction C1 when viewed from above. In the second gentle slope 102A of each second blade portion 100B, each protrusion 230 is an arc shape that bulges slightly towards the second direction C2 when viewed from above. In the two second gentle slopes 102A located on both sides of each second recess 120, a plurality of protrusions 230 are symmetrically arranged sandwiching the bottom surface 121 when viewed from above.

[0068] Details of the second recess 120 are described below. Figures 2 to 4As shown, the stirring blade 70 has a first region on one surface, which is located between two adjacent blade portions 100 on the circumferential C of the stirring blade 70 and is recessed from the blade portion 100. In this example, two second recesses 120 provided on the upper surface 71 of the stirring blade 70 respectively illustrate the first region. The shapes of the two second recesses 120 are approximately identical when rotated 180 degrees relative to each other about the rotation axis O. Hereinafter, the construction of one second recess 120 will be described, and the construction of the remaining second recesses 120 will be omitted.

[0069] The stirring blade 70 has a first protrusion 210 that protrudes from the bottom surface of the first region and extends in a direction intersecting the radial direction. In this example, the first protrusion 210 has an arcuate shape that bulges outward and opens inward when viewed from above. Specifically, in the second recess 120, which is the first region, a plurality of (four in this example) first protrusions 210 protruding upward from the bottom surface 121 are provided. The plurality of first protrusions 210 are arranged radially at intervals from each other. The plurality of first protrusions 210 are arranged symmetrically about an imaginary vertical plane passing through the apex of the first protrusion 210 and the rotation axis O when viewed from above. The construction of one first protrusion 210 will be described below, but the construction of the remaining first protrusions 210 is the same.

[0070] like Figure 7 As shown, the first protrusion 210 has a first bearing surface 211 facing radially inward and a second bearing surface 212 facing radially outward with an inclination angle smaller than that of the first bearing surface 211. In this example, the cross-section orthogonal to the extending direction of the first protrusion 210 is a triangular shape projecting upward from the bottom surface 121 to the end point 213. The first bearing surface 211 extends obliquely downward from the end point 213 toward the inner side of the arcuate shape depicted by the first protrusion 210 when viewed from above. The second bearing surface 212 extends obliquely downward from the end point 213 toward the outer side of the arcuate shape depicted by the first protrusion 210 when viewed from above. The arcuate shape depicted by the first protrusion 210 is a roughly semi-ellipse that bulges radially outward and opens radially inward when viewed from above. Therefore, the first bearing surface 211 as a whole faces radially inward, and the second bearing surface 212 as a whole faces radially outward.

[0071] The inclination angle θ21 of the first bearing surface 211 relative to the bottom surface of the first region is larger than the inclination angle θ22 of the second bearing surface 212. In this example, the plane passing through the boundary between the bottom surface 121 of the second recess 120 (which is the first region) and the first protrusion 210 is taken as the imaginary plane V21. The inclination angle θ21 is equal to the angle formed by the imaginary plane V21 and the first bearing surface 211. The inclination angle θ22 is equal to the angle formed by the imaginary plane V21 and the second bearing surface 212.

[0072] exist Figure 7In the example, the tilt angle θ21 is approximately 60 degrees, and the tilt angle θ22 is approximately 30 degrees. Therefore, the tilt angle θ21 is greater than the tilt angle θ22. Thus, the first bearing surface 211 is a steep slope with a relatively large gradient relative to the bottom surface 121. The second bearing surface 212 is a gentle slope with a relatively small gradient relative to the bottom surface 121. Furthermore, the angle formed by the end 213 of the first protrusion 210 is equal to the interior angle formed by the first bearing surface 211 and the second bearing surface 212, for example, 90 degrees.

[0073] As described above, two second side surfaces 102 of blade portions 100 are provided on both sides of the second recess 120, and a plurality of protrusions 230 are provided on these second side surfaces 102. The cross-sectional shape of these protrusions 230 is the same as that of the first protrusion 210, which is a triangular shape protruding upward from the second side surface 102, and has a first bearing surface 231 and a second bearing surface 232 extending from each end toward the second side surface 102. In each protrusion 230, the first bearing surface 231 faces the adjacent second recess 120 side, and the second bearing surface 232 faces the adjacent blade portion 100 side. Therefore, the first bearing surface 231 and the second bearing surface 232 face different directions of rotation from each other.

[0074] In each protrusion 230, the inclination angle of the first bearing surface 231 relative to the second side surface 102 is greater than the inclination angle of the second bearing surface 232 relative to the second side surface 102. Figure 7 In the example, the inclination angle of the first bearing surface 231 is approximately 60 degrees, and the inclination angle of the second bearing surface 232 is approximately 30 degrees. Therefore, the first bearing surface 231 is a steep slope with a relatively large gradient relative to the second side surface 102, and the second bearing surface 232 is a gentle slope with a relatively small gradient relative to the second side surface 102.

[0075] like Figures 2 to 4 As shown, each of the two blade portions 100 adjacent to the first region includes a side surface extending from the bottom of the first region toward the edge R side of the blade portion 100. The inclination angle of the side surface relative to an imaginary plane orthogonal to the rotation axis O is smaller in the radially outer direction than in the radially inner direction. In this example, on both sides of the second recess 120, which is the first region, the second side surface 102 of the first blade portion 100A and the second side surface 102 of the second blade portion 100B extend from the bottom surface 121 toward the corresponding edge R side, respectively. As described above, the inclination angle θ12 of these second side surfaces 102 decreases from the radially inner direction toward the radially outer direction (see reference). Figure 5 as well as Figure 6 ).

[0076] like Figure 4 as well as Figure 7As shown, the bottom surface 121 of the second recess 120, which is the first region, has a bend or inclination that is displaced upward toward the radially inward side. In this example, the lowermost part 121A of the bottom surface 121 extends in an arc shape along the outer periphery of the stirring blade 70 in the top view. The bottom surface 121 is a smooth curved surface that is continuously displaced upward in a manner that gradually rises radially inward from the lowermost part 121A.

[0077] As described above, in the second recess 120, the second side surface 102 of the first blade portion 100A and the second side surface 102 of the second blade portion 100B are opposite each other in the circumferential direction C. The second gently sloping surface 102A located radially outward in the second side surface 102 has a relatively small inclination angle θ12 relative to the horizontal plane (see reference). Figure 6 Therefore, the lengths of the two second gentle slopes 102A located on both sides of the second recess 120 in the circumferential direction C are relatively large. The radially outer region of the bottom surface 121 of the second recess 120, sandwiched between the two second gentle slopes 102A, has a relatively narrow width in the circumferential direction C.

[0078] In the first blade portion 100A adjacent to the second recess 120, the radially outer second ridge line R2 extends in a manner that bends towards the second direction C2. In the ridge line R of the second blade portion 100B adjacent to the second recess 120, the radially outer second ridge line R2 extends in a manner that bends towards the first direction C1. That is, in the two blade portions 100 located on both sides of the second recess 120, they bend towards the second recess 120 in a manner that their respective second ridge lines R2 approach each other. As a result, in the region radially outer of the second recess 120, the distance between the two blade portions 100 located on both sides becomes smaller. In the region radially outer of the bottom surface 121, compared to the case where the second ridge lines R2 of each blade portion 100 extend in a manner consistent with the radial direction, the width of the circumferential direction C is further narrowed.

[0079] Furthermore, the second steep slope 102B located radially inward in the second side 102 has a relatively large inclination angle θ12 relative to the horizontal plane (see reference). Figure 5 Therefore, the lengths of the two second steep slopes 102B located on both sides of the second recess 120 in the circumferential direction C are relatively small. A gap is formed in the radially inner region of the second recess 120, sandwiched between the two second steep slopes 102B. The bottom surface 121 of the second recess 120 extends radially inward from the lowest part 121A, and further extends into the vicinity of the center of the stirring blade 70 within this gap.

[0080] The details of the first recess 110 are described below. Figures 2 to 4As shown, the stirring blade 70 has a second region in a region different from the first region on one side of the stirring blade 70. The second region is disposed between two blade portions 100 adjacent to the circumferential C of the stirring blade 70 and is recessed from the blade portion 100. In this example, the second region is illustrated by two first recesses 110 provided on the upper surface 71 of the stirring blade 70. The shapes of the two first recesses 110 are approximately identical when rotated 180 degrees relative to each other about the rotation axis O. Hereinafter, the construction of one first recess 110 will be described, and the construction of the remaining first recesses 110 will be omitted.

[0081] The stirring blade 70 has a second protrusion 220 protruding from the bottom surface of the second region. In this example, a plurality of (three in this example) second protrusions 220 protruding upward from the bottom surface 111 are provided in the first recess 110, which is the second region. The shape of these second protrusions 220 is different from the shape of the first protrusion 210 described above. Hereinafter, one construction of the second protrusion 220 will be described, but the construction of the remaining second protrusions 220 is the same.

[0082] like Figure 8 As shown, the end 221 of the second protrusion 220 is relative to the end 213 of the first protrusion 210 (see reference). Figure 7 The angle is obtuse. In this example, the second protrusion 220 is a spherical shape that bulges slightly upward from the bottom surface 111. The angle formed by the end 221 of the second protrusion 220 is the same as the angle formed by the plane relative to the spherical surface, i.e., the vertex of the second protrusion 220, for example, 180 degrees. Therefore, the angle formed by the end 221 is larger than the angle formed by the end 213 mentioned above (for example, 90 degrees).

[0083] The second protrusion 220 is a spherical shape with an inclination angle of less than 30 degrees relative to the bottom surface of the second region. In this example, the plane passing through the boundary between the bottom surface 111 of the first concave portion 110 of the second region and the second protrusion 220 is taken as an imaginary plane V22. The inclination angle θ23 is the same as the contact angle of the sphere relative to the imaginary plane V22, for example, 25 degrees.

[0084] like Figures 2 to 4As shown, the stirring blade 70 has a plurality of second protrusions 220 arranged radially parallel to the surface. In this example, the three second protrusions 220 include a second protrusion 220A located radially inner to the bottom surface 111 and two second protrusions 220B and 220C located radially outer to the bottom surface 111. The second protrusion 220C is located on the first direction C1 side relative to the second protrusion 220B. The second protrusions 220A and 220B are adjacent to the first blade portion 100A on the first direction C1 side and are arranged along the extending direction of the first blade portion 100A. Since the first blade portion 100A extends radially, these second protrusions 220A and 220B are arranged radially parallel to the surface. In addition, the second protrusions 220A and 220C are adjacent to the second blade portion 100B on the second direction C2 side and are arranged along the extending direction of the second blade portion 100B. Since the second blade portion 100B extends radially, these second protrusions 220A, 220C are arranged parallel to the radial direction.

[0085] Each of the two blade portions 100 adjacent to the second region includes a side surface extending from the bottom of the second region toward the edge R side of the blade portion 100. The inclination angle of the side surface relative to an imaginary plane orthogonal to the rotation axis O is larger in the radially outer direction than in the radially inner direction. In this example, on both sides of the first recess 110, which is the second region, the first side surface 101 of the first blade portion 100A and the first side surface 101 of the second blade portion 100B extend from the bottom surface 111 toward the corresponding edge R side, respectively. As described above, the inclination angle θ11 of these first side surfaces 101 increases from the radially inner direction toward the radially outer direction (see reference). Figure 5 as well as Figure 6 ).

[0086] like Figure 4 and Figure 8 As shown, the bottom surface 111 of the first recess 110, which is the second region, has a bend or inclination that is displaced upward toward the radially inward side. In this example, the lowermost part 111A of the bottom surface 111 extends in an arc shape along the outer periphery of the stirring blade 70 in the top view. The bottom surface 111 is a smooth curved surface that is continuously displaced upward in a manner that gradually rises in the radially inward side from the lowermost part 111A.

[0087] As described above, in the first recess 110, the first side surface 101 of the first blade portion 100A and the first side surface 101 of the second blade portion 100B are opposite each other in the circumferential direction C. The first steep slope 101B located radially outward in the first side surface 101 has a relatively large inclination angle θ11 relative to the horizontal plane (see reference). Figure 6Therefore, the lengths of the two first steep slopes 101B located on both sides of the first recess 110 in the circumferential direction C are relatively small. The radially outer region of the bottom surface 111 of the first recess 110, sandwiched between the two first steep slopes 101B, has a relatively wide width in the circumferential direction C.

[0088] In the first blade portion 100A adjacent to the first recess 110, the radially outer second ridge line R2 extends in a manner that bends towards the second direction C2. In the ridge line R of the second blade portion 100B adjacent to the first recess 110, the radially outer second ridge line R2 extends in a manner that bends towards the first direction C1. That is, in the two blade portions 100 located on both sides of the first recess 110, they bend towards the opposite side of the first recess 110 in a manner that their respective second ridge lines R2 are far apart. As a result, in the region radially outer of the first recess 110, the distance between the two blade portions 100 located on both sides of it increases. In the radially outer region of the bottom surface 111, compared to the case where the second ridge lines R2 of each blade portion 100 extend in a manner consistent with the radial direction, the width of the circumferential direction C further increases.

[0089] Furthermore, the first gently sloping surface 101A located radially inward in the second side 102 has a small angle of inclination θ11 relative to the horizontal plane (see reference). Figure 5 Therefore, the two first gentle slopes 101A located on both sides of the first recess 110 have relatively large lengths in the circumferential direction C. A joint portion is formed in the radially inner region of the first recess 110 to join the two first gentle slopes 101A together. The bottom surface 111 of the first recess 110 extends radially inward from the lowest part 111A to the joint portion.

[0090] [Structure of the lower surface of the stirring blades] Details of blade body 300 are explained. Figure 9 This is a three-dimensional view of the stirring blade 70 when viewed from a slightly downward angle. Figure 10 This is a bottom view of the stirring blade 70. Figure 11 It is along Figure 10 A cross-sectional view of the VV line in the direction of view.

[0091] like Figure 9 and Figure 10 As shown, the stirring blade 70 has a blade body 300 that protrudes axially from one face of the stirring blade 70 and extends radially outward from the radially inner side of the rotation axis O. In this example, a plurality of blade bodies 300 protruding downward from the lower surface 72 of the stirring blade 70 are arranged circumferentially C. Four blade bodies 300 are arranged circumferentially C at approximately 90-degree intervals and extend radially from near the center of the stirring blade 70 to the outer periphery along the rotation axis O.

[0092] In the manufacturing process of the stirring blade 70, the four blade portions 100 are formed such that they bulge upwards on the upper surface 71. Directly below the four blade portions 100, four grooves 310 are formed such that their lower surface 72 is recessed upwards, corresponding to the shape of each blade portion 100. The four blade bodies 300 are respectively disposed within these grooves 310 (see reference). Figure 5 and Figure 6 ).

[0093] Each groove 310 has a bottom surface 330 extending radially in relation to the upper end face 103 of the corresponding blade portion 100, directly below the upper end face 103. As described above, the groove 310 is recessed upwards, so the bottom surface 330 corresponds to the top surface within the groove 310. The blade body 300 is a plate-shaped member extending downwards from the bottom surface 330 of the groove 310 and radially within the groove 310. The length direction of the blade body 300 is radial, and the short side direction of the blade body 300 is vertical.

[0094] The stirring blade 70 includes a blade body 300 and a first opposing surface 301 facing each other in the circumferential direction C. The first opposing surface 301 extends radially inward to radially outward on one surface of the stirring blade 70, and is inclined relative to the axial direction in a manner that the further away from the blade body 300 the more it is from that surface towards the axial direction. In this example, each groove portion 310 has a first opposing surface 301 with a shape corresponding to the second side surface 102 of the corresponding blade portion 100 directly below it. The first opposing surface 301 extends downward from the bottom surface 330 of the groove portion 310, and faces the blade body 300 in the circumferential direction C at a distance from it. The first opposing surface 301 extends obliquely downward from the lower surface 72 in a manner that moves away from the blade body 300 as it moves downward. The first opposing surface 301 is an inclined surface that extends radially outward when viewed from below.

[0095] In detail, the four grooves 310 include two first grooves 310A corresponding to the two first blade portions 100A and two second grooves 310B corresponding to the two second blade portions 100B. The two first grooves 310A are located on both sides of the lower surface 72 sandwiching the central portion, and have a substantially identical shape when rotated 180 degrees around the circumference C. Similarly, the two second grooves 310B are located on both sides of the lower surface 72 sandwiching the central portion, and have a substantially identical shape when rotated 180 degrees around the circumference C. The adjacent first grooves 310A and second grooves 310B are symmetrical about an imaginary vertical plane sandwiched by their intermediate positions.

[0096] In each first groove 310A, the first opposing surface 301 extends from the edge of the bottom surface 330 on the second direction C2 side in a manner that shifts downwards towards the second direction C2. The first opposing surface 301 of the first groove 310A faces the first direction C1 side and is opposite to the side surface of the adjacent blade body 300 on the second direction C2 side. In each second groove 310B, the first opposing surface 301 extends from the edge of the bottom surface 330 on the first direction C1 side in a manner that shifts downwards towards the first direction C1. The first opposing surface 301 of the second groove 310B faces the second direction C2 side and is opposite to the side surface of the adjacent blade body 300 on the first direction C1 side. Therefore, the first opposing surfaces 301 of the first groove 310A and the first opposing surfaces 301 of the second groove 310B face opposite directions.

[0097] like Figure 5 and Figure 6 As shown, the tilt angle θ31 of the first opposing surface 301 is smaller on the radially outer side than on the radially inner side. The tilt angle θ31 is the angle formed by the first opposing surface 301 with respect to an imaginary plane V3 orthogonal to the rotation axis O. The imaginary plane V3 is synonymous with a plane extending parallel to the rotation direction of the stirring blade 70. In this example, the tilt angle θ31 is the size of the angle formed by the horizontal imaginary plane V3 and the first opposing surface 301 in a cross-section that cuts the groove 310 orthogonally to the extension direction of the groove 310 through any point on the first opposing surface 301.

[0098] The first opposing surface 301 has a bottom surface 330 of the groove 310 (see reference). Figure 10 The upper end of the first opposing surface 301 is connected to the lower end of the groove 310. The tilt angle θ31 is equal to the angle between the imaginary straight line L31 passing through the upper and lower ends of the first opposing surface 301 and the imaginary plane V3. The imaginary straight line L31 can be a tangent at any point on the first opposing surface 301, for example, it can be a tangent at the lower end of the first opposing surface 301.

[0099] In detail, when the imaginary plane V3 is positioned lower than the groove 310, when viewed from the radially outer side, the angle of the region containing the second opposing surface 302 of the groove 310 within the multiple regions divided by the imaginary line L31 and the imaginary plane V3 is the tilt angle θ31. In other words, the tilt angle θ31 represents the slope of the first opposing surface 301 relative to the horizontal imaginary plane V3; the larger the angle, the steeper the slope of the first opposing surface 301. The first opposing surface 301 is tilted in such a way that the tilt angle θ31 continuously decreases from the radially inner side to the radially outer side. The portion closer to the center of the stirring blade 70 becomes a steeper slope of the first opposing surface 301, and the portion closer to the outer periphery of the stirring blade 70 becomes a gentler slope of the first opposing surface 301.

[0100] In this example, since the first opposing surface 301 and the second side surface 102 located above it have corresponding shapes, the tilt angle θ31 of the first opposing surface 301 is substantially equal to the tilt angle θ12 of the second side surface 102. Furthermore, the tilt angle θ31 is inversely proportional to the circumferential opening width of the first flow path 311 (described later); the smaller the angle, the larger the opening width of the first flow path 311. The closer to the center of the stirring blade 70, the smaller the opening width of the first flow path 311; and the closer to the outer periphery of the stirring blade 70, the larger the opening width of the first flow path 311.

[0101] like Figure 9 and Figure 10 As shown, the stirring blade 70 has a second opposing surface 302, which is disposed on the opposite side of the first opposing surface 301, separated from the blade body 300, and is opposite to the blade body 300 in the circumferential direction C. In this example, each groove portion 310 has a second opposing surface 302 with a shape corresponding to the first side surface 101 of the corresponding blade portion 100 directly below it. The second opposing surface 302 extends downward from the bottom surface 330 of the corresponding groove portion 310 and is spaced apart from the blade body 300 in the circumferential direction C. Each blade body 300 is sandwiched between the first opposing surface 301 and the second opposing surface 302 disposed on both sides in the circumferential direction C, and is opposite to these first opposing surfaces 301 and the second opposing surface 302.

[0102] The second opposing surface 302 extends radially inward from radially outward on one surface of the stirring blade 70, and is inclined relative to the axial direction such that it moves further away from the blade body 300 as it moves towards the axial direction. In this example, the second opposing surface 302 extends obliquely downward from the lower surface 72 such that it moves further away from the blade body 300 as it moves downward. The second opposing surface 302 is an inclined surface that narrows radially outward when viewed from below. Specifically, in each of the four grooves 310, the second opposing surface 302 is provided as follows.

[0103] In each first groove 310A, the second opposing surface 302 extends downward from the edge of the bottom surface 330 in the first direction C1 direction. The second opposing surface 302 of the first groove 310A faces the second direction C2 direction and is opposite to the side surface of the adjacent blade body 300 in the first direction C1 direction. In each second groove 310B, the second opposing surface 302 extends downward from the edge of the bottom surface 330 in the second direction C2 direction. The second opposing surface 302 of the second groove 310B faces the first direction C1 direction and is opposite to the side surface of the adjacent blade body 300 in the second direction C2 direction. Therefore, the second opposing surfaces 302 of the first groove 310A and the second opposing surfaces 302 of the second groove 310B face opposite directions.

[0104] like Figure 5 and Figure 6 As shown, the bottom surface 330 of each groove 310 (refer to) Figure 10 The blade body 300 includes a first bottom surface 331 and a second bottom surface 332 separated on both sides of the corresponding blade body 300. The first bottom surface 331 extends between the blade body 300 and a first opposing surface 301 opposite to the blade body 300. The second bottom surface 332 extends between the blade body 300 and a second opposing surface 302 opposite to the blade body 300. Each groove 310 is divided by the corresponding blade body 300 into two first flow paths 311 and a second flow path 312 arranged in the circumferential direction C. The first flow path 311 is a groove-shaped region surrounded by the blade body 300, the first bottom surface 331, and the first opposing surface 301 and extending radially. The second flow path 312 is a groove-shaped region surrounded by the blade body 300, the second bottom surface 332, and the second opposing surface 302 and extending radially.

[0105] The tilt angle θ32 of the second opposing surface 302 is larger on the radially outer side than on the radially inner side. The tilt angle θ32 is the angle between the second opposing surface 302 and an imaginary plane V3 orthogonal to the axis of rotation O. In this example, the tilt angle θ32 is the angle between the horizontal imaginary plane V3 and the second opposing surface 302 in a cross-section that cuts through the groove 310 orthogonally to the extending direction of the groove 310, passing through any point on the second opposing surface 302.

[0106] The second opposing surface 302 has an upper end portion connected to the bottom surface 330 of the groove 310 and a lower end portion located at the lower end of the groove 310. The tilt angle θ32 is equal to the angle formed by an imaginary straight line L32 passing through the upper and lower ends of the second opposing surface 302 and an imaginary plane V3. The imaginary straight line L32 can be a tangent relative to any point on the second opposing surface 302, for example, it can be a tangent at the lower end of the second opposing surface 302.

[0107] In detail, when the imaginary plane V3 is positioned lower than the groove 310, when viewed from the radially outer side, the angle of the region containing the first opposing surface 301 of the groove 310 within the multiple regions divided by the imaginary line L32 and the imaginary plane V3 is the tilt angle θ32. In other words, the tilt angle θ32 represents the slope of the second opposing surface 302 relative to the horizontal imaginary plane V3; the larger the angle, the steeper the slope of the second opposing surface 302. The second opposing surface 302 is tilted such that the tilt angle θ32 continuously increases from the radially inner side to the radially outer side. The portion closer to the center of the stirring blade 70 becomes a gentle slope with a small gradient, and the portion closer to the outer periphery of the stirring blade 70 becomes a steep slope with a large gradient.

[0108] In this example, since the second opposing surface 302 and the first side surface 101 located above it have corresponding shapes, the tilt angle θ32 of the second opposing surface 302 is substantially equal to the tilt angle θ11 of the first side surface 101. Furthermore, the tilt angle θ32 is inversely proportional to the circumferential opening width of the second flow path 312; the smaller the angle, the larger the opening width of the second flow path 312. The closer to the center of the stirring blade 70, the larger the opening width of the second flow path 312; and the closer to the outer periphery of the stirring blade 70, the smaller the opening width of the second flow path 312.

[0109] like Figures 9 to 11 As shown, each blade body 300 includes an inner portion 300A located radially inward and an outer portion 300B located radially outward than the inner portion 300A. The axial height H2 of the outer portion 300B is greater than the axial height H1 of the inner portion 300A. In this example, in the blade body 300, the first ridge line R1 located in the blade portion 100 (refer to...) Figure 4 The lower part of the blade portion 100 is the inner part 300A, located on the second ridge line R2 (refer to the blade portion 100). Figure 4 The lower part of ) is the outer part 300B.

[0110] For example, the maximum vertical length of the inner portion 300A is defined as height H1. The maximum vertical length of the outer portion 300B is defined as height H2. Since height H2 is greater than height H1, the outer portion 300B is longer than the inner portion 300A in the vertical direction. Alternatively, height H1 can be the average vertical length of the inner portion 300A, and height H2 can be the average vertical length of the outer portion 300B.

[0111] like Figure 5 , Figure 6 and Figure 11As shown, one surface of the stirring blade 70 includes a first bottom surface 331 of a first flow path 311 formed between the blade body 300 and the first opposing surface 301. In this example, the lower surface 72 of the stirring blade 70 includes the first bottom surface 331 of the first flow path 311. The first bottom surface 331 is a smooth surface that is continuous in the radial direction, and therefore extends smoothly without any bumps or steps except for the drain hole.

[0112] Any second point in the first bottom surface 331 is designated as the first point P1, and a second point P2 is located radially outward from the first point. An imaginary plane V3, orthogonal to the rotation axis O, is positioned axially away from the first bottom surface 331. In this case, the distance D2 from the second point P2 to the imaginary plane V3 is greater than the distance D1 from the first point P1 to the imaginary plane V3. In this example, any two points radially away from each other in the first bottom surface 331 are designated as the first point P1 and the second point P2, in order of distance from the rotation axis O from closest to farthest. A horizontal plane extending downward from the first bottom surface 331 is designated as the imaginary plane V3.

[0113] Distance D1 represents the height of the first point P1 relative to the imaginary plane V3. Distance D2 represents the height of the second point P2 relative to the imaginary plane V3. In the first bottom surface 331 where distance D2 is greater than distance D1, the second point P2 is located at the same height as or higher than the first point P1, and the first point P1 is located radially inside the second point P2. Therefore, the first bottom surface 331 is composed of at least one of a face that is continuously raised to a certain height in the vertical direction towards the radially outward direction and a face that is continuously raised in the vertical direction towards the radially outward direction. In other words, the first bottom surface 331 does not include a face that is displaced downward in the vertical direction towards the radially outward direction.

[0114] The lower surface 72 of the stirring blade 70 includes a second bottom surface 332 of the second flow path 312. The second bottom surface 332 is a smooth surface that is continuous in the radial direction. Similarly, any two points in the second bottom surface 332 are designated as a first point P1 and a second point P2, and an imaginary plane V3 is positioned axially away from the second bottom surface 332. In this case, the distance D2 from the second point P2 to the imaginary plane V3 is greater than or equal to the distance D1 from the first point P1 to the imaginary plane V3.

[0115] [How the washing machine operates] Explain the operating method of washing machine 1. Figures 12A to 12F This is a schematic longitudinal sectional view of a washing machine 1 in operation. During the washing cycle of the washing machine 1, the forward rotation of the agitator blades 70 in a first direction C1 and the reverse rotation of the agitator blades 70 in a second direction C2 are alternately repeated at predetermined intervals. Figures 12A to 12D In this example, the stirring blade 70 is driven to rotate forward. Figure 12E In this example, the stirring blade 70 is temporarily stopped to change its rotation direction. Figure 12F In the example, the stirring blade 70 is driven in reverse.

[0116] like Figure 1 and Figure 12A As shown, when the stirring blade 70 rotates, it passes through the plurality of blade portions 100 (refer to) provided on the upper surface 71 of the stirring blade 70. Figure 2 A water flow X is generated in the circumferential direction C. Multiple grooves 310 (see reference) are located on the lower surface 72 of the stirring blade 70. Figure 9 This forms a water channel, and the water in each groove 310 flows radially inward to radially outward due to centrifugal force. At this time, in each groove 310, the corresponding blade body 300 (refer to...) Figure 9 The water is scraped outwards radially, thus forming a strong water flow toward the peripheral wall 30B of the mixing tank 30.

[0117] Water flowing from each tank section 310 forms an upward water flow Y along the peripheral wall 30B through the gap 34 between the agitator blades 70 and the peripheral wall 30B. Since a downward water flow Z is generated near the center of rotation above the agitator blades 70, the water continues to circulate within the agitator tank 30 through the downward water flow Z and the upward water flow Y. The forward and reverse rotation of the agitator blades 70 is repeated alternately at predetermined intervals, thereby producing the following behavior on the washings W on the upper surface 71 side.

[0118] [The behavior of the washing material on the upper surface of the agitator blades] Explain the behavior of the washing material W on the upper surface 71 side of the stirring blade 70. For example... Figure 12A As shown, with the forward rotation of the stirring blades 70, multiple washes W move along the water flow X and gradually move radially outward by means of centrifugal force (refer to arrow F1). Within the mixing tank 30, the multiple washes W concentrate on the side of the peripheral wall 30B where the circumferential speed of the stirring blades 70 is high, thus increasing the density of washes W per unit area on the peripheral wall 30B side. As a result, as... Figure 12B As shown, on the side of the peripheral wall 30B inside the mixing tank 30, multiple washes W that are densely aggregated gradually descend due to their own weight (refer to arrow F2).

[0119] like Figure 12C As shown, when the washing material W, as described above, falls radially outward toward the upper surface 71 of the agitator blade 70, it is pushed radially inward toward the agitator blade 70. As the washing material W is pushed outward, other washing materials W overlapping it are also pulled radially inward. That is, on the upper surface 71 of the agitator blade 70, multiple washing materials W move from radially outward to radially inward (refer to arrow F3).

[0120] This explains the principle by which the washing material W moves radially inward toward the stirring blade 70. Figures 13A to 13C as well as Figure 16 This is a schematic side view showing an enlarged view of a portion of the upper surface 71 of the agitator blade 70, which is equipped with the washing material W. For ease of understanding, Figures 13A to 13C and Figure 16 When viewed from the radial outer side of the stirring blade 70, the first recess 110, the first blade portion 100A, the second recess 120, and the second blade portion 100B, arranged along the circumferential direction C, are all unfolded in a planar shape. Figure 14 This is a schematic top view of the upper surface 71 of the stirring blade 70 equipped with the washing material W. Figure 15A It is a schematic longitudinal sectional view of the first recess 110 where the laundry item W is disposed. Figure 15B It is a schematic longitudinal sectional view of the second recess 120 where the detergent W is disposed.

[0121] like Figure 13A As shown, when multiple washes W descend along the peripheral wall 30B within the mixing tank 30, they fall into the first recess 110 and the second recess 120 (refer to arrow F11). The washes W falling into the first recess 110 and the second recess 120 are pressed by the side of the blade portion 100 located upstream of the washes W in the rotation direction, moving in a manner that rotates together with the mixing blade 70. At this time, in each of the first recess 110 and the second recess 120, a gap G without washes W is created adjacent to each blade portion 100 on the upstream side in the rotation direction.

[0122] exist Figure 13A In the example shown, the stirring blade 70 rotates along the first direction C1. Therefore, the detergent W within the first recess 110 moves by being pressed by the first side surface 101 of the first blade portion 100A located on the second direction C2 side. A gap G is created along the first blade portion 100A in the second recess 120 located on the second direction C2 side of the first blade portion 100A. Furthermore, the detergent W within the second recess 120 moves by being pressed by the second side surface 102 of the second blade portion 100B located on the second direction C2 side. A gap G is created along the second blade portion 100B in the first recess 110 located on the second direction C2 side of the second blade portion 100B.

[0123] Above the washing material W that is pressed and rotated by the blade portion 100, a subsequent washing material W that has not yet fallen onto the stirring blade 70 is attached. The blade portion 100, which rotates together with the stirring blade 70, moves along the first direction C1 such that it passes beneath the subsequent washing material W. Thus, as Figure 13BAs shown, subsequent washes W move relative to each other on the upper side of the blade portion 100 and fall into the gap G (refer to arrow F12) of the first recess 110 or the second recess 120 located on the second direction C2 side of the blade portion 100. Thus, a plurality of washes W are accommodated on the radially outer side of the first recess 110 and the radially outer side of the second recess 120.

[0124] like Figure 13C As shown, the laundry W located in the first recess 110 and the second recess 120 is moved by being pressed by the sides of the blade portions 100, thereby becoming compressed by being pressed against the sides of these blade portions 100. Specifically, the first blade portion 100A presses the laundry W located radially outward of the first recess 110 using the first steep slope 101B of the first side surface 101. The second blade portion 100B presses the laundry W located radially outward of the second recess 120 using the second gentle slope 102A of the second side surface 102.

[0125] As described above, the inclination angle θ11 of the first steep slope 101B is larger than the inclination angle θ12 of the second gentle slope 102A. Therefore, the first steep slope 101B is closer to vertical than the second gentle slope 102A (see reference). Figure 6 When the washing material W is opposite the first steep slope 101B in the circumferential direction C as the stirring blade 70 rotates, the angle difference between the horizontal circumferential direction C and the first steep slope 101B is... Figure 6 The tilt angle θ11 is also relatively large. Since the laundry W is facing the first steep slope 101B and has difficulty escaping upwards, the first steep slope 101B captures the laundry W without escape, thereby powerfully compressing multiple laundry Ws.

[0126] On the other hand, when the washing material W and the second gentle slope 102A are opposite each other in the circumferential direction C as the stirring blade 70 rotates, the angle difference between the horizontal circumferential direction C and the second gentle slope 102A is... Figure 6 The inclination angle θ12 is also relatively small. Therefore, there is a possibility that the laundry W may escape upward along the second gentle slope 102A. When the laundry W easily escapes upward along the second gentle slope 102A, multiple pieces of laundry W may flow out of the second recess 120. To suppress this, as described above, a protrusion 230 is provided that protrudes upward from the second gentle slope 102A and extends in a direction intersecting the circumferential direction C (see reference). Figure 7 ).

[0127] In the protrusion 230, the inclination angle of the first bearing surface 231 facing the second recess 120 is larger than that of the second bearing surface 232 facing the blade portion 100. Therefore, the first bearing surface 231 is closer to being perpendicular to the second side surface 102 than the second bearing surface 232. When the laundry W located in the second recess 120 moves upward along the second side surface 102, the angle difference between the direction of movement of the laundry W and the first bearing surface 231 is relatively large, thus increasing the contact friction between the laundry W and the protrusion 230. This large contact friction helps to prevent excessive flow of the laundry W from the second recess 120.

[0128] Additionally, in the second side 102, sometimes the laundry W moves along the second gentle slope 102A towards the second steep slope 102B radially inward (see reference). Figure 7 When the laundry W easily escapes upwards along the second steep slope 102B, multiple loads of laundry W may flow out of the second recess 120. To suppress this, as described above, the inclination angle θ12 of the second steep slope 102B is larger than the inclination angle θ12 of the second gentle slope 102A (see reference). Figure 5 as well as Figure 6 Therefore, the second steep slope 102B with a large tilt angle θ12 can capture the laundry W that is moving relative to it in the circumferential direction C, thus preventing the laundry W from flowing out excessively from the second recess 120.

[0129] exist Figure 13C In the example, the wash W located radially outward of the first recess 110 is pushed and moved by the first steep slope 101B, and is therefore compressed relatively strongly (see arrow F13). The wash W located radially outward of the second recess 120 is pushed and moved by the second gentle slope 102A, and is therefore compressed relatively weakly (see arrow F14). Therefore, on the radially outward side of the stirring blade 70, the density of the wash W per unit area in the first recess 110 is greater than the density of the wash W per unit area in the second recess 120.

[0130] like Figure 14 As shown, in each of the first recess 110 and the second recess 120, a plurality of detergent Ws are compressed to a high density, thereby pushing a portion of these detergent Ws radially inward. At this point, the greater the density of the detergent Ws per unit area, the greater the intensity of pushing the detergent Ws radially inward.

[0131] exist Figure 14In this example, on the radially outer side of the first recess 110 where the laundry W is pressed by the first steep slope 101B, the compressibility of the laundry W is relatively high, thus the force pushing the laundry W radially inward is relatively strong (see arrow F15). On the radially outer side of the second recess 120 where the laundry W is pressed by the second gentle slope 102A, the compressibility of the laundry W is relatively low, thus the force pushing the laundry W radially inward is relatively weak (see arrow F16). In this example, the first recess 110 that presses the laundry W with strong force and the second recess 120 that presses the laundry W with weak force are distributed in an alternating manner along the circumferential direction C.

[0132] In each of the first recess 110 and the second recess 120, the laundry W pushed radially inward is pulled, and subsequent laundry W also moves radially inward. Figure 14 In the example, the laundry W moves from the radially outer side to the radially inner side on both sides of the rotation axis O sandwiched by the two first recesses 110. Similarly, the laundry W moves from the radially outer side to the radially inner side on both sides of the rotation axis O sandwiched by the two second recesses 120. However, the force exerted by the first recesses 110 to move the multiple laundry W radially inward is greater than that of the second recesses 120 (see arrows F15, F16).

[0133] As described above, a second protrusion 220 is provided that protrudes from the bottom surface 111 of the first recess 110 (see reference). Figure 8 ).like Figure 15A As shown, in the first recess 110, the laundry W is supported from below by a plurality of second protrusions 220 and is pushed or pulled radially inward as described above. Thus, since contact between the laundry W and the bottom surface 111 is suppressed, the laundry W can move smoothly radially inward.

[0134] As described above, the end 221 of the second protrusion 220 is at an obtuse angle relative to the end 213 of the first protrusion 210 (see reference). Figure 7 , Figure 8 In this example, the second protrusion 220 is spherical with an inclination angle of less than 30 degrees relative to the bottom surface 111 of the first recess 110. The contact friction between the laundry item W and the second protrusion 220 is less than the contact friction between the laundry item W and the first protrusion 210. Therefore, in the first recess 110, where the force causing the laundry item W to move radially inward is relatively large, the laundry item W is not hindered by the second protrusion 220 and can easily move radially inward.

[0135] As described above, a plurality of second protrusions 220 arranged radially parallel are provided (see reference). Figure 4In this example, within the first recess 110, the radially inward movement of the detergent W is substantially equal to the movement of the detergent W along the blade portion 100 adjacent to the first recess 110 toward the rotation axis O. Within the first recess 110, two second protrusions 220A and 220B are arranged along the extending direction of the blade portion 100 on the second direction C2 side, and two second protrusions 220A and 220C are arranged along the extending direction of the blade portion 100 on the first direction C1 side. The extending direction of the blade portion 100 is substantially parallel to the radial direction of the stirring blade 70.

[0136] Therefore, when the wash W is facing the rotation axis O along the blade portion 100 on the second direction C2 side, it can move smoothly towards the rotation axis O because it is supported by the two second protrusions 220A and 220B. Similarly, when the wash W is facing the rotation axis O along the blade portion 100 on the first direction C1 side, it can also move smoothly towards the rotation axis O because it is supported by the two second protrusions 220A and 220C.

[0137] As described above, the bottom surface 111 of the first recess 110 has a bend or inclination that is displaced radially inward and upward (see reference). Figure 8 Therefore, the wash W, which moves radially inward within the first recess 110, is exerted with force obliquely upward along the surface shape of the bottom surface 111, and is released from near the radially inward end of the first recess 110 toward the upper side of the stirring blade 70 (see reference). Figure 12D ).

[0138] As described above, a first protrusion 210 is provided that protrudes from the bottom surface 121 of the second recess 120 and extends in a direction intersecting the radial direction (see reference). Figure 7 ).like Figure 15B As shown, in the second recess 120, the laundry item W is supported from below by a plurality of first protrusions 210 and is pushed or pulled radially inward as described above. Thus, since contact between the laundry item W and the bottom surface 121 can be suppressed, the laundry item W can move smoothly radially inward. However, in the second recess 120, since the force causing the laundry item W to move radially inward is relatively small, the laundry item W may potentially return from the radially inward side to the radially outward side.

[0139] As described above, the first protrusion 210 has a first bearing surface 211 facing radially inward and a second bearing surface 212 facing radially outward and having an inclination angle smaller than that of the first bearing surface 211 (see reference). Figure 7In the first protrusion 210, the first bearing surface 211 is closer to being perpendicular than the second bearing surface 212. When the laundry item W moves radially outward on the first protrusion 210, the angle difference between the direction of movement of the laundry item W and the first bearing surface 211, as well as the tilt angle θ21, is relatively large, thus increasing the contact friction between the laundry item W and the first protrusion 210. On the other hand, when the laundry item W moves radially inward on the first protrusion 210, the angle difference between the direction of movement of the laundry item W and the second bearing surface 212, as well as the tilt angle θ22, is relatively small, thus decreasing the contact friction between the laundry item W and the first protrusion 210.

[0140] That is, the detergent W is easy to move radially inward and difficult to move radially outward on the first protrusion 210, thus preventing the detergent W from returning radially inward to radially outward. This suppresses unwanted reciprocating motion of the detergent W, thereby improving the washing effect of the detergent W washed in the mixing tank 30. For example, since the detergent W spreads out in a manner that prevents wrinkles from forming on the mixing blades 70, uneven washing of the detergent W is suppressed, and the cleaning force removing dirt from the detergent W per unit time is increased.

[0141] As described above, the first protrusion 210 has an arcuate shape that bulges outward and opens inward (see reference). Figure 4 Therefore, when the laundry W returns radially outward within the second recess 120, at least a portion of the laundry W traverses the first protrusion 210 in a manner substantially orthogonal to its extending direction. At this point, the first bearing surface 211 generates maximum contact friction at the location where the direction of movement of the laundry W intersects the extending direction of the first protrusion 210. This high contact friction more reliably prevents the laundry W from returning radially outward.

[0142] As described above, the bottom surface 121 of the second recess 120 has a bend or inclination that is displaced radially inward and upward (see reference). Figure 7 Therefore, the wash W moving radially inward within the second recess 120 is exerted with force obliquely upward along the surface shape of the bottom surface 121, and is released from near the radially inward end of the second recess 120 toward the upper side of the stirring blade 70 (see reference). Figure 12D ).

[0143] like Figure 12D As shown, multiple washes W moving radially inward on the upper surface 71 are released onto the upper side of the stirring blade 70 as described above (refer to arrow F4). Figure 12EAs shown, when the rotation direction of the stirring blade 70 is switched, the rotation of the stirring blade 70 temporarily stops. At this time, in order to restore the water level in the mixing tank 30 to the level when it is not rotating, an upward water flow Z1 is generated near the center of rotation above the stirring blade 70, and a downward water flow Y1 is generated along the peripheral wall 30B.

[0144] That is, a vortex X1 is formed between the rotation center side and the outer peripheral side within the mixing tank 30 by the rising water flow Z1 and the falling water flow Y1. The vortex X1 is a water flow rotating around the circumferential center C, with the upper side of the vortex X1 facing the outer peripheral side and the lower side of the vortex X1 facing the rotation center side. Multiple pieces of detergent W rotate with the vortex X1, thereby promoting vertical and radial movement within the mixing tank 30. Furthermore, it is possible to reliably generate a situation within the mixing tank 30 where floating and sinking detergent W exchange positions.

[0145] like Figure 12F As shown, when the stirring blade 70 is driven in reverse, compared to when the stirring blade 70 rotates forward (refer to...), Figure 12A Similarly, water flows X, Y, and Z are generated. However, the direction of water flow X during reverse rotation is opposite to the direction of water flow X during forward rotation. The subsequent movement of the stirring blades 70 and the behavior of the washings W are similar to... Figures 12A to 12E same.

[0146] In addition, such as Figure 16 As shown, immediately after the rotation direction of the stirring blade 70 is switched, the detergent W retained in the first recess 110 and the second recess 120 is lifted above the stirring blade 70 by colliding with the side of the blade portion 100 upstream of the direction of rotation of the detergent W (refer to arrows F21 and F22). In this way, by releasing the detergent W retained in the first recess 110 and the second recess 120 upward when the rotation direction of the stirring blade 70 is switched, the amount of detergent W moved can be increased, and multiple detergent Ws can be evenly dispersed.

[0147] Furthermore, when the stirring blade 70 reverses direction, the wash residue W on the radially outer side of each first recess 110 is relatively strongly pressed by the first steep slope 101B of the first side surface 101 of the second blade portion 100B. The wash residue W located on the radially outer side of each second recess 120 is relatively weakly pressed by the second gentle slope 102A of the second side surface 102 of the first blade portion 100A. Therefore, when the stirring blade 70 rotates forward (refer to...), the wash residue W on the radially outer side of each second recess 120 is relatively weakly pressed by the second gentle slope 102A of the second side surface 102 of the first blade portion 100A. Figure 14 Similarly, the first recess 110 of the wash W is pressed hard and the second recess 120 of the wash W is pressed weakly, and they are dispersed in an alternating manner along the circumferential direction C.

[0148] According to this embodiment, as described above, the tilt angle θ11 of the first side 101 is larger on the radially outer side than on the radially inner side (refer to...). Figure 5 and Figure 6 Therefore, the radially outer region of the first side surface 101 becomes a first steep slope 101B with a large inclination angle θ11. When the agitator blade 70 rotates, the first steep slope 101B moves while reliably capturing the wash material W, thus increasing the amount of wash material W moving in the circumferential direction C. Furthermore, on the radially outer side of the agitator blade 70, where the circumferential speed is relatively high, the multiple wash materials W captured by the first steep slope 101B are compressed with high density. Since the compressed wash material W is pushed radially inward, the amount of wash material W moving radially is increased.

[0149] As the movement of the detergent W on the stirring blades 70 is promoted in both the circumferential and radial directions, the amount of movement of the detergent W per unit time increases, thereby improving the washing effect of the detergent W washed in the mixing tank 30. For example, since the water flow can more easily contact the entire detergent W, uneven washing of the detergent W can be suppressed, while the washing force of the detergent W per unit time is increased. Furthermore, by repeatedly rotating the stirring blades 70 in both directions, as described above, the detergent W moves from the radially inward side upward, promoting the behavior of the upper and lower detergent W exchanging positions with the vortex X1. By reliably generating this behavior, multiple detergents W can be washed effectively, thereby further improving the washing effect of the detergent W.

[0150] As described above, the first side surface 101 of the first blade portion 100A faces the first direction C1, and the first side surface 101 of the second blade portion 100B faces the second direction C2 (see reference). Figure 3 Therefore, when the stirring blade 70 rotates in the first direction C1, the first steep slope 101B of the first blade portion 100A easily captures the detergent W, while the first steep slope 101B of the second blade portion 100B has difficulty capturing the detergent W. When the stirring blade 70 rotates in the second direction C2, the first steep slope 101B of the first blade portion 100A easily captures the detergent W, while the first steep slope 101B of the second blade portion 100B has difficulty capturing the detergent W.

[0151] In this way, the blade portion 100 that captures the laundry W is switched according to the rotation direction of the agitator blade 70. This prevents the load of the laundry W from concentrating on specific blade portions 100, thereby reducing the possibility of damage to the blade portions 100 due to load concentration. Furthermore, since it is possible to prevent all blade portions 100 from simultaneously bearing the load of the laundry W, the number of motors 41 driving the rotation of the agitator blade 70 (see reference) can be reduced. Figure 1 The load is concentrated.

[0152] As described above, the two blade portions 100 adjacent to the first recess 110 each have a first side surface 101 extending from the bottom of the first recess 110 to the edge R side of the blade portion 100. The first side surface 101 of the first blade portion 100A and the first side surface 101 of the second blade portion 100B extend from the same first recess 110 and are opposite to each other in the circumferential direction C (see reference). Figure 4 Therefore, regardless of whether the stirring blade 70 rotates in the first direction C1 or the second direction C2, the first steep slope 101B can capture the washing material W in the first recess 110 on either of the two first side surfaces 101 on both sides of the first recess 110.

[0153] As described above, in the ridge line R of the first blade portion 100A, the second ridge line R2 includes a portion that bends and extends from the first ridge line R1 toward the second direction C2. In the ridge line R of the second blade portion 100B, the second ridge line R2 includes a portion that bends and extends from the first ridge line R1 toward the first direction C1 (see reference). Figure 4 Therefore, since the second ridge line R2 of the first blade portion 100A and the second ridge line R2 of the second blade portion 100B bend in opposite directions, the length of the radially outer side of the first recess 110 in the circumferential direction C increases. Thus, more laundry W can be accommodated on the radially outer side of the first recess 110 and can be captured by the first steep slope 101B.

[0154] As described above, the second side surface 102 includes a second gentle slope 102A, which is positioned parallel to the first steep slope 101B in the circumferential direction C. The inclination angle θ12 of the second gentle slope 102A is smaller than the inclination angle θ11 of the first steep slope 101B (refer to...). Figure 5 and Figure 6 Therefore, the radially outer region of the second side 102 becomes a second gently sloping surface 102A with a smaller inclination angle θ12. When the stirring blade 70 rotates, the second gently sloping surface 102A, like the first steeply sloping surface 101B, captures the detergent W, thus increasing the amount of detergent W moving in both the circumferential and radial directions. However, the force with which the second gently sloping surface 102A captures the detergent W is weaker than that of the first steeply sloping surface 101B.

[0155] Therefore, in the first recess 110 of the first steep slope 101B that captures the detergent W, the force capturing the detergent W is relatively strong. In the second recess 120 of the second gentle slope 102A that captures the detergent W, the force capturing the detergent W is relatively weak. Thus, the agitator blade 70 has a first recess 110 and a second recess 120 with different forces capturing the detergent W. As a result, it is possible to suppress the simultaneous strong capture of the detergent W by all recesses, thereby reducing the motor 41 (see reference) that drives the rotation of the agitator blade 70. Figure 1 The load is concentrated.

[0156] Furthermore, in the first recess 110, the force that moves the wash W radially inward is relatively strong. In the second recess 120, the force that moves the wash W radially inward is relatively weak. Radially inward of the agitator blade 70, the wash W moving with a relatively strong force takes precedence over the wash W moving with a relatively weak force. Thus, by setting varying strengths for the forces that move the multiple wash W radially inward, it is possible to prevent these wash Ws from interfering with each other and becoming entangled.

[0157] As described above, the two blade portions 100 adjacent to the second recess 120 each have a second side surface 102 extending from the bottom of the second recess 120 to the edge R side of the blade portion 100. The second gentle slope surface 102A of the first blade portion 100A and the second gentle slope surface 102A of the second blade portion 100B extend from the same second recess 120 and are opposite to each other in the circumferential direction C (see reference). Figure 4 Therefore, regardless of whether the stirring blade 70 rotates in the first direction C1 or the second direction C2, the second gentle slope 102A can capture the washing material W in the second recess 120 in either of the two second side surfaces 102 on both sides of the second recess 120.

[0158] [The generation of water flow on the lower surface of the stirring blades] The following describes the water flow generated on the lower surface 72 side of the stirring blade 70. Figure 17 and Figure 18 This is a schematic bottom view showing an enlarged portion of the lower surface 72 of the stirring blade 70. Figure 17 schematically shown Figure 10 The upper first groove 310A and its surrounding area are shown among the four grooves 310 shown. Figure 18 schematically shown Figure 10 The second groove 310B on the upper right of the four grooves 310 shown, and its surrounding area.

[0159] like Figure 17 and Figure 18 As shown, when the stirring blade 70 rotates in the first direction C1, the water moves relative to the lower surface 72 side in the second direction C2 (refer to arrows Y11 and Y21). The closer to the radially outer side of the stirring blade 70, the faster the circumferential speed of the stirring blade 70, and therefore the faster the relative flow velocity of the water. In this case, the water flow described below is generated in the four tanks 310.

[0160] like Figure 17 As shown, in each of the two first grooves 310A, the second opposing surface 302 is located on the first direction C1 side of the blade body 300. Therefore, water moving relative to the first grooves 310A flows through the underside of the second opposing surface 302 and into the blade body 300 within the first groove 310A.

[0161] As described above, the tilt angle θ32 of the second opposing surface 302 is radially outward (refer to...). Figure 6 ) compared to the radially inner side (refer to Figure 5 When the second opposing surface 302 is larger, the radially inner side is closer to horizontal than the radially outer side. On the radially outer side of the second opposing surface 302, the angular difference between the second direction of relative water movement C2 and the second opposing surface 302 is... Figure 6 The tilt angle θ32 is also relatively large, and as mentioned above, the water flow velocity is relatively fast. Therefore, the water moving relatively towards the second direction C2 is difficult to flow along the radially outer side of the second opposing surface 302, but instead moves in a straight line away from the radially outer side of the second opposing surface 302, thus making it difficult to flow into the second flow path 312.

[0162] On the radially inner side of the second opposing surface 302, the angular difference between the second direction of relative water movement C2 and the second opposing surface 302 is... Figure 5 The tilt angle θ32 is also relatively small, and as mentioned above, the water flow velocity is relatively slow. Therefore, the water moving relatively towards the second direction C2 is guided upward along the radially inner side of the second opposing surface 302, and easily flows into the second flow path 312 (refer to arrow Y11). Thus, in the second flow path 312, water with a relatively slow flow velocity easily flows in, so the water inflow per unit time may be relatively small.

[0163] In contrast, the second opposing surface 302 is an inclined surface that narrows radially outward in the top view. The width of the second flow path 312 is the interval between the second opposing surface 302 and the blade body 300, which gradually narrows radially outward. Therefore, as the water flowing into the second flow path 312 moves radially outward within the flow path, the water velocity increases (refer to arrow Y12). Thus, the water flow Y10 with increased velocity is scraped out by the blade body 300 rotating in the first direction C1 and sent radially outward from the open end of the second flow path 312.

[0164] like Figure 18 As shown, in each of the two second grooves 310B, the first opposing surface 301 is located on the first direction C1 side of the blade body 300. Therefore, water moving relative to the second grooves 310B flows past the underside of the first opposing surface 301 and into the blade body 300 within the second groove 310B.

[0165] As described above, the tilt angle θ31 of the first opposing surface 301 is radially outward (refer to...). Figure 6 ) compared to the radially inner side (refer to Figure 5 When the time is small. In the first opposing surface 301, the radially outer side is closer to horizontal than the radially inner side. On the radially outer side of the first opposing surface 301, the angular difference between the second direction C2 of the relative movement of water and the first opposing surface 301 is smaller. Figure 6The tilt angle θ31 is also relatively small. Therefore, even if the water flow rate is relatively fast, the water is guided upward along the first opposing surface 301 and easily flows into the first flow path 311 (refer to arrow Y21).

[0166] On the radially inner side of the first opposing surface 301, the angular difference between the second direction C2 of the relative movement of water and the first opposing surface 301 is... Figure 5 The tilt angle θ31 is also relatively small. However, as mentioned above, since the water flow rate is relatively slow, the water is guided upward along the first opposing surface 301 and easily flows into the first flow path 311 (refer to arrow Y21). Thus, water with a wide range of flow rates can easily flow into the first flow path 311, and therefore the water inflow per unit time is also relatively large.

[0167] The first opposing surface 301 is an inclined surface that extends radially outward in the top view. Therefore, the width of the first flow path 311 gradually widens radially outward. As the water flowing into the first flow path 311 moves radially outward within the flow path, faster-flowing water merges, thus increasing the velocity and volume of the water flow formed within the flow path (refer to arrow Y22). In this way, the water flow Y20 with increased velocity and volume is ejected radially outward from the open end of the first flow path 311 by being scraped out by the blade body 300 rotating in the first direction C1.

[0168] like Figure 14 As shown, when the stirring blade 70 rotates clockwise in the first direction C1, water flows Y10 in opposite directions are discharged from the two first grooves 310A located below the two first blade portions 100A to the outside of the stirring blade 70. Water flows Y20 in opposite directions are discharged from the two second grooves 310B located below the two second blade portions 100B to the outside of the stirring blade 70. Thus, the stirring blade 70 can radially discharge multiple water flows Y10 and Y20 with relatively high flow rates in a manner that is arranged at approximately equal intervals along the circumference. These water flows Y10 and Y20 form a water flow Y that rises through the gap 34 as described above (see reference). Figure 1 ).

[0169] When the stirring blade 70 reverses direction C2, the functions of the first groove 310A and the second groove 310B are interchanged. Specifically, in each of the two first grooves 310A, water flows into the first flow path 311 through the lower side of the first opposing surface 301, thereby sending water flow Y20 radially outward. In each of the two second grooves 310B, water flows into the second flow path 312 through the lower side of the second opposing surface 302, thereby sending water flow Y10 radially outward. At this time, similar to when the stirring blade 70 rotates forward, multiple faster water flows Y10 and Y20 are radially sent out from the stirring blade 70, forming water flow Y.

[0170] As described above, in the blade body 300, the axial height H2 of the outer portion 300B is greater than the axial height H1 of the inner portion 300A (refer to...). Figure 11 In the first groove 310A and the second groove 310B of each groove 310, the water flow velocity increases towards the radially outer side, making it potentially more difficult to control the flow. Conversely, since the vertical width of the outer portion 300B is greater than that of the inner portion 300A, it can prevent a portion of the water flowing radially outward from escaping across the blade body 300 in the direction of rotation. Therefore, the blade body 300 can scrape out almost all the water located within each groove 310, efficiently discharging the high-velocity water flow.

[0171] As described above, in the blade body 300, the distance D1 from the second point P2 to the imaginary plane V3 is greater than or equal to the distance D2 from the first point P1 to the imaginary plane V3 (refer to...). Figure 11 That is, the first bottom surface 331 and the second bottom surface 332 do not include any surface that is displaced radially outward in the vertical direction. Therefore, the water flowing in the first flow path 311 is smoothly released radially outward along the first bottom surface 331 (see reference). Figure 18 The water flowing in the second flow path 312 is smoothly released radially outward along the second bottom surface 332 (see reference). Figure 17 ).

[0172] In this example, the first bottom surface 331 and the second bottom surface 332 are smooth surfaces that slope radially outward and upward. Water flows Y10 and Y20 flowing in the first flow path 311 and the second flow path 312 are easily released obliquely upward from the outer periphery of the stirring blade 70 along the surface shape of the first bottom surface 331 and the second bottom surface 332. Therefore, water flows Y10 and Y20 can accurately pass through the gap 34 on the outer periphery of the stirring blade 70 (see reference). Figure 1 ), forming a water flow Y without reducing the flow velocity.

[0173] According to the stirring blade 70 of this embodiment, since the flow rate of the water delivered from the lower surface 72 side is increased, the amount of movement of the laundry W on the upper surface 71 side per unit time can be increased. Therefore, even if the amount of water in the stirring tank 30 is small, the washing effect of the laundry W can be improved. For example, by forming a high-speed water flow on the upper surface 71 side, uneven washing of the laundry W can be suppressed, while the washing force of the laundry W per unit time is increased.

[0174] [Remark] This disclosure is not limited to the above-described embodiments and various modifications are possible. In the above embodiments, a vertical washing machine 1 with a rotating shaft O extending in the vertical direction is illustrated. Alternatively, the washing machine 1 may be a washing machine with a rotating shaft O extending in a direction intersecting the vertical direction, such as a drum washing machine. The agitator blade 70 may only have any one of the various structures on the upper surface 71 side and the various structures on the lower surface 72 side. For example, the agitator blade 70 may have the various structures on the upper surface 71 side, while the lower surface 72 side is the same as a conventional agitator blade.

[0175] On the upper surface 71 side of the stirring blade 70, the number, shape, size, and position of the blade portion 100, the first recess 110, the second recess 120, etc., can be arbitrarily designed and changed. For example, only one blade portion 100 can be provided on the upper surface 71 of the stirring blade 70, or two or more blade portions 100 can be provided. When multiple blade portions 100 are provided, the first blade portion 100A and the second blade portion 100B can be combined, or only multiple first blade portions 100A can be provided, or only multiple second blade portions 100B can be provided.

[0176] On the lower surface 72 side of the stirring blade 70, the number, shape, size, and position of the blade body 300, the first opposing surface 301, the second opposing surface 302, and the groove 310 can be arbitrarily designed and changed. For example, only one blade body 300 and groove 310 can be provided on the lower surface 72 of the stirring blade 70, or two or more blade bodies 300 and grooves 310 can be provided. When multiple grooves 310 are provided, the first groove 310A and the second groove 310B can be combined, or only multiple first grooves 310A can be provided, or only multiple second grooves 310B can be provided.

[0177] This disclosure is not limited to the embodiments described above, and various modifications can be made within the scope of the claims. Embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of this invention. Moreover, new technical features can be formed by combining the technical methods disclosed in each embodiment. Claims (as amended under Article 19 of the Treaty) 1. A stirring blade capable of stirring a fluid by rotation about a rotation axis, characterized in that it comprises: A blade body that projects axially from one face of the stirring blade and extends radially outward from the radially inner side of the rotation axis; and The first opposing surface is spaced apart from the blade body in the circumferential direction of the stirring blade. The tilt angle of the first opposing surface on the radially outer side is smaller than the tilt angle on the radially inner side. 2. The stirring blade according to claim 1, characterized in that it further comprises: The second opposing surface is disposed on the opposite side of the first opposing surface, separated from the blade body, and is spaced apart from the blade body in the circumferential direction. The tilt angle of the second opposing surface increases as it moves from the radially inner side toward the radially outer side. 3. The stirring blade according to claim 1, characterized in that, The blade body includes an inner portion located radially inward and an outer portion located radially outward. The axial height of the outer part is greater than the axial height of the inner part. 4. The stirring blade according to claim 1, characterized in that, The surface includes the bottom surface of a groove formed between the blade body and the first opposing surface. When any two points on the bottom surface are designated as a first point and a second point located further radially outward than the first point, and the imaginary plane is positioned axially away from the bottom surface, the distance from the second point to the imaginary plane is greater than the distance from the first point to the imaginary plane. 5. The stirring blade according to claim 1, characterized in that, The surface in question is the lower surface of the stirring blade. The blade body is a flat plate that protrudes from the lower surface in a downward direction parallel to the axial direction and extends from the radially inner side to the radially outer side. The distance between the blade body and the first opposing surface increases continuously from the radially inner end of the blade body toward the radially outer end of the blade body. 6. The stirring blade according to claim 2, characterized in that, The surface in question is the lower surface of the stirring blade. The blade body is a flat plate that protrudes from the lower surface in a downward direction parallel to the axial direction and extends from the radially inner side to the radially outer side. The distance between the blade body and the first opposing surface increases continuously from the radially inner end of the blade body toward the radially outer end of the blade body. The distance between the blade body and the second opposing surface decreases continuously from the radially inner end of the blade body toward the radially outer end of the blade body. 7. A washing machine, characterized in that it includes an agitator blade according to any one of claims 1 to 6.

Claims

1. A stirring blade capable of stirring a fluid by rotation about a rotation axis, characterized in that, include: The blade body protrudes axially from one face of the stirring blade and extends radially outward from the radially inner side of the rotation axis; as well as The first opposing surface is opposite to the blade body in the circumferential direction of the stirring blade. The tilt angle of the first opposing surface on the radially outer side is smaller than the tilt angle on the radially inner side.

2. The stirring blade according to claim 1, characterized in that, Also includes: The second opposing surface is disposed on the opposite side of the first opposing surface, separated from the blade body, and is opposite to the blade body in the circumferential direction. The tilt angle of the second opposing surface increases as it moves from the radially inner side toward the radially outer side.

3. The stirring blade according to claim 1, characterized in that, The blade body includes an inner portion located radially inward and an outer portion located radially outward. The axial height of the outer part is greater than the axial height of the inner part.

4. The stirring blade according to claim 1, characterized in that, The surface includes the bottom surface of a groove formed between the blade body and the first opposing surface. When any two points on the bottom surface are designated as a first point and a second point located further radially outward than the first point, and the imaginary plane is positioned axially away from the bottom surface, the distance from the second point to the imaginary plane is greater than the distance from the first point to the imaginary plane.

5. A washing machine, characterized in that, Includes stirring blades according to any one of claims 1 to 4.

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