Centrifuges and washing machines equipped with centrifuges

Abstract

The centrifuge (200) includes: a drive unit (240); a centrifugal separation unit (204) having a housing (210) and a rotating drum (220); and a swirling flow generating unit (205). The swirling flow generating unit (205) includes: a fluid inlet (250) having a first peripheral wall (252); and a cylindrical section (270). The first peripheral wall (252) has an inlet (285) for allowing washing water to flow in, and guides the washing water flowing into the inflow space (261) in a swirling manner. The cylindrical section (270) is located between the fluid inlet (250) and the centrifugal separation unit (204), causing the washing water swirling in the fluid inlet (250) to swirl and be introduced into the centrifugal separation unit (204). The cylindrical portion (270) includes a second circumferential wall portion (271), in which at least a portion of the cylindrical portion (270) in the axial direction is formed as a cone with a gradually decreasing diameter from the housing (210) toward the fluid inlet portion (250).

Description

Technical Field

[0001] This invention relates to a centrifugal separator and a washing machine equipped with a centrifugal separator. Background Technology

[0002] Centrifuges are sometimes used to separate and remove foreign matter from liquid fluids such as washing water, bath water and organic wastewater (see, for example, Patent Document 1). Figure 7 This is a cross-sectional view that schematically represents the structure of the conventional centrifuge 300 disclosed in Patent Document 1. Figure 8 This is a schematic cross-sectional view showing the structure of a conventional centrifuge 300 as viewed from below. (See attached image.) Figure 7 As shown, the centrifuge 300 disclosed in Patent Document 1 has a swirling flow generating section 320 that makes the washing water flowing into the centrifugal separation section 310 into a swirling flow, and an inlet pipe 330 for introducing washing water into the swirling flow generating section 320.

[0003] like Figure 8 As shown, the swirling flow generating section 320 has an annular peripheral wall portion 322, which has an inlet 321 for washing water to flow in from the inlet pipe 330. In the swirling flow generating section 320, the washing water flowing in from the inlet 321 flows along the inner peripheral surface of the peripheral wall portion 322, thereby generating a swirling flow... Figure 8 The arrow indicates the direction of the swirling flow.

[0004] like Figure 7 As shown, the centrifugal separation unit 310 includes: a rotating cylinder 311 disposed within a housing 340; and a pump unit 312, which is composed of a plurality of pump blades integrally formed with the rotating cylinder 311. The rotating cylinder 311 and the pump unit 312 are coaxially disposed with respect to a circular space enclosed by the peripheral wall portion 322 of the swirling flow generating unit 320. A drive unit 350 is disposed on the outside of the housing 340 for driving the rotating cylinder 311 and the pump unit 312.

[0005] If the drive unit 350 drives the pump unit 312, then as Figure 7 As shown by the middle arrow, the washing water flowing from the washing tub of the washing machine passes sequentially through the inlet pipe 330, the swirling flow generating section 320, and the rotating drum 311. If the washing water flows into the swirling flow generating section 320 through the inlet pipe 330, it flows along the inner circumferential surface of the peripheral wall section 322. Therefore, the washing water becomes a swirling flow within the peripheral wall section 322. The swirling washing water then flows from the swirling flow generating section 320 into the rotating drum 311. The rotating drum 311 is driven to rotate by the drive section 350, thus increasing the angular velocity of the swirling flow due to the rotation of the rotating drum 311, and increasing the centrifugal force acting on foreign matter contained in the swirling flow. As a result, the foreign matter is centrifugally separated within the rotating drum 311.

[0006] Existing technical documents

[0007] Patent documents

[0008] Patent Document 1: Japanese Patent Application Publication No. 2018-183277 Summary of the Invention

[0009] In this conventional centrifuge 300, the wash water is pressurized by the pump section 312, so the pressure of the wash water at the nozzle 315 of the centrifugal separation section 310 is greater than the pressure of the wash water at the opening 345 at the lower end of the housing 340. Due to this pressure difference, a portion of the wash water flowing from the rotating drum 311 to the nozzle 315 will flow back from the outer circumferential surface of the rotating drum 311 and the housing 340 towards the opening 345. Furthermore, the wash water flowing back to the opening 345 at the lower end of the housing 340 may flow back to the swirling flow generating section 320.

[0010] The countercurrent washing water may obstruct the flow of washing water flowing in from the inlet pipe 330 at the inlet 321 of the swirling flow generating section 320. In this case, the swirling flow within the swirling flow generating section 320 becomes turbulent. Therefore, there is a risk of a decrease in the angular velocity of the swirling flow and a decrease in the centrifugal force exerted by the centrifugal separation section 310 on the foreign matter.

[0011] Therefore, the present invention provides a centrifuge configured to suppress the reduction of centrifugal force acting on foreign matter in the centrifugal separation section and a washing machine equipped with the centrifuge.

[0012] The centrifuge of the present invention separates foreign matter contained in a liquid fluid. The centrifuge includes: a drive unit that generates driving force; a centrifugal separation unit; and a swirling flow generating unit connected to the centrifugal separation unit. The centrifugal separation unit has a housing and a rotating cylinder disposed within the housing and rotated by the driving force of the drive unit. The centrifugal separation unit centrifugally separates foreign matter from the fluid within the rotating cylinder. The swirling flow generating unit includes a fluid inlet and a cylindrical section. The fluid inlet has a first circumferential wall portion, which forms an inlet for fluid inflow and guides the fluid flowing into the inflow space inside the first circumferential wall portion in a manner that causes the fluid to swirl. The cylindrical section is located between the fluid inlet and the centrifugal separation unit, causing the fluid swirling in the fluid inlet to swirl and be introduced into the centrifugal separation unit. The cylindrical section includes a second circumferential wall portion, in which at least a portion of the cylindrical section in the axial direction is formed as a cone with a diameter that gradually decreases from the housing towards the fluid inlet.

[0013] The washing machine of the present invention includes: the centrifugal separator described above; and a washing tub for washing laundry. The centrifugal separator is connected to the washing tub in such a way that fluid from the washing tub flows into the centrifugal separator.

[0014] The centrifugal separator and the washing machine equipped with the centrifugal separator described above can suppress the reduction of the centrifugal force acting on foreign objects in the centrifugal separator when the fluid flows counter-currently from the centrifugal separation section to the swirling flow generation section. Attached Figure Description

[0015] Figure 1 This is a longitudinal structural diagram that schematically shows the structure of the washing machine according to the first embodiment.

[0016] Figure 2 It is a longitudinal sectional view that roughly shows the structure of the centrifugal separator installed in the washing machine.

[0017] Figure 3 It is a cross-sectional view that roughly represents the structure of the centrifuge as seen from below.

[0018] Figure 4 This is a cross-sectional view that schematically shows the structure of a modified centrifuge of the first embodiment as viewed from below.

[0019] Figure 5A This is a longitudinal sectional view showing the structure of a centrifuge according to a modified example of the first embodiment.

[0020] Figure 5B This is a longitudinal sectional view showing the structure of a centrifuge according to a modified example of the first embodiment.

[0021] Figure 6 This is a longitudinal sectional view that schematically shows the structure of the centrifuge according to the second embodiment.

[0022] Figure 7 It is a cross-sectional view that roughly represents the structure of a conventional centrifuge.

[0023] Figure 8 It is a cross-sectional view that roughly represents the structure of a conventional centrifuge as seen from below. Detailed Implementation

[0024] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, in order to facilitate understanding by those skilled in the art, detailed descriptions of known matters or repeated descriptions of substantially the same structures may be omitted. Furthermore, the accompanying drawings and the following description are provided to enable those skilled in the art to fully understand the present invention and are not intended to limit the subject matter described in the claims.

[0025] (First Embodiment)

[0026] like Figure 1 As shown, the washing machine of the first embodiment of the present invention is configured as a rotary drum type washing machine 100. Figure 1 This is a longitudinal structural diagram that schematically represents the structure of the washing machine 100. Furthermore, in this embodiment, a rotary drum washing machine is described as an example, but the washing machine of the present invention is not limited to this. In short, the washing machine of the present invention can be any washing machine that uses washing water to wash laundry. That is, the present invention can also be applied to washing machines with any structure, such as a rotary drum washing machine that performs tumbling washing, a vertical washing machine that performs agitation washing, or a washing or rinsing machine that performs pressing washing within a housing. Additionally, in this embodiment, sometimes... Figure 1 The vertical direction shown in the configuration of washing machine 100 is described as the up-down direction. Additionally, sometimes... Figure 1 The left side of the text is described as the front side of the washing machine 100. Figure 1 The right side of the text is described as the rear side of washing machine 100.

[0027] (The overall structure of a washing machine)

[0028] The washing machine 100 includes: a housing 110 having an inlet for loading laundry 101; and a door 111 for opening and closing the inlet of the housing 110. Specifically, the inlet is formed on the front wall of the housing 110, and the door 111 is closably mounted on the front wall of the housing 110. Various internal devices for performing washing, rinsing, and spin-drying processes are housed within the housing 110.

[0029] A washing tub 115 for washing laundry 101 is provided inside the outer casing 110. The washing tub 115 includes: a water tank 112 having an opening that opens toward the door 111 in the closed state; and a rotating drum 120 configured to rotate within the water tank 112. Furthermore, laundry 101 can be clothing or other products that can be washed in the washing machine 100, such as non-clothing fibers.

[0030] The water tank 112 is provided for accumulating washing water (an example of the liquid fluid of the present invention) during the washing and rinsing processes. The water tank 112 is elastically supported by a suspension mechanism 114 fixed to the bottom wall of the housing 110.

[0031] To prevent washing water from leaking out of the opening of the sink 112, a sealing member 113 is provided at the opening of the sink 112. The sealing member 113 is compressed by the door 111 when the door 111 closes the inlet.

[0032] A water inlet 116 is provided on the upper part of the peripheral wall of the water tank 112, which allows washing water to flow in during the washing and rinsing processes. In addition, an outlet 117 and an inlet 118 are provided at the lower part of the water tank 112. The outlet 117 is used to discharge the washing water used in the washing and rinsing processes of the laundry 101, and the inlet 118 allows the washing water discharged from the outlet 117 to return to the water tank 112.

[0033] The rotating drum 120 is positioned at an angle towards the forward direction within the water tank 112. The rotating drum 120 opens towards the inlet (door 111 in the closed state) of the outer casing 110, and the laundry 101 is contained within the rotating drum 120 through this opening. Numerous small holes 124 are formed on the peripheral and rear walls of the rotating drum 120, through which washing water flows in and out relative to the rotating drum 120 during the washing and rinsing processes.

[0034] A protrusion 123 is disposed inside the rotating drum 120. In addition, a drive unit 121 for rotating the rotating drum 120 and the protrusion 123 is installed on the outer surface of the rear wall of the sink 112. When the rotating drum 120 and the protrusion 123 rotate, the laundry 101 held inside the rotating drum 120 can be moved.

[0035] The protrusion 123 protrudes from the center of the rear wall of the rotating drum 120 toward the opening of the rotating drum 120. The protrusion 123 is configured to rotate together with the rotating drum 120, and the washings 101 inside the rotating drum are agitated or lifted by the rotation of the protrusion 123.

[0036] The drive unit 121 may also be configured as a motor (e.g., a brushless DC motor) capable of forward and reverse rotation. The shaft of this motor protrudes into the interior of the water tank 112 through a through hole provided in the rear wall of the water tank 112, and is connected to the rotating drum 120 and the protrusion 123. The drive unit 121 is configured to change the rotational speed of the rotating drum 120 and the protrusion 123 under frequency conversion control.

[0037] A water supply unit 139 is provided on the upper side of the sink 112. The water supply unit 139 is used to supply washing water to the laundry 101 in the rotating drum 120. The water supply unit 139 includes a water supply path 130 disposed on the upper side of the sink 112, a water supply valve 131 disposed on the water supply path 130, and a detergent tank 132.

[0038] The upstream end of the water supply path 130 is configured to be exposed on the outer surface of the housing 110 and can be connected to a flexible hose (not shown) extending from the faucet 102 of the water pipe. The downstream end of the water supply path 130 is connected to the water inlet 116 of the sink 112.

[0039] The water supply valve 131 is configured to open and close the water supply path 130, and is positioned upstream of the detergent tank 132 in the direction of water flow within the water supply path 130. The detergent tank 132 is configured to hold detergent. Furthermore, the detergent tank 132 is configured to allow water to flow through it when the water supply valve 131 is opened.

[0040] A circulation path 143 is provided on the lower side of the water tank 112, with both ends connected to the outlet 117 and inlet 118 of the water tank 112. A centrifuge 200 is provided on the circulation path 143, which is configured to centrifuge the foreign matter (fibers, etc.) from the washing water flowing through the circulation path 143. The circulation path 143 includes: a drain pipe 144 extending between the centrifuge 200 and the outlet 117; and a return pipe 145 extending between the centrifuge 200 and the inlet 118. The drain pipe 144 and the return pipe 145 can be constructed from general flexible hose components with a circular cross-section.

[0041] A discharge path 140 branches off from the drain pipe 144. A drain valve 142 is provided in the discharge path 140 for opening and closing the discharge path 140.

[0042] A control unit 170 is provided for controlling the drive unit 121, water supply valve 131, drain valve 142, and centrifuge 200. The control unit 170 is located near the lower part of the front wall of the housing 110. The control unit 170 is electrically connected to the drive unit 121, water supply valve 131, drain valve 142, and centrifuge 200.

[0043] In addition to the control unit 170, there are also multiple instruments (not shown) that detect the torque applied to the drive unit 121, the rotational speed of the drive unit 121, and the amount of washing water supplied to the water tank 112. These instruments are connected to the control unit 170. The detection values ​​from these instruments are used for control by the control unit 170.

[0044] As an example, the control unit 170 can be composed of a microcomputer and peripheral circuits, an arithmetic processing unit and a storage unit for storing control programs, hard logic circuits, or a combination of the above components. When the control unit 170 is composed of an arithmetic processing unit and a storage unit, an MPU (Microprocessor Unit) and a CPU (Central Processing Unit) can be used as the arithmetic processing unit. A memory storing the control program can be used as the storage unit. The control program stored in the memory is executed by the arithmetic processing unit. If the control unit 170 is composed of hard logic circuits, the processing speed can be improved. The hard logic circuits can be composed of a single semiconductor chip or multiple semiconductor chips.

[0045] (Structure of a centrifuge)

[0046] Figure 2 This is a longitudinal sectional view schematically showing the structure of the centrifugal separator 200 mounted on the washing machine 100. The centrifugal separator 200 is configured to centrifuge and separate foreign matter contained in the washing water flowing through the circulation path 143. Figure 2 As shown, the centrifugal separator 200 includes: a centrifugal separation section 204 for centrifugally separating foreign matter in the washing water; a drive section 240 for generating a driving force to drive the centrifugal separation section 204; and a swirling flow generating section 205 disposed below the centrifugal separation section 204 to generate a swirling flow. The centrifugal separator 200 is mounted inside the washing machine 100 with the axis of rotation of the swirling flow approximately vertical. An inflow section 260 connected to a drain pipe 144 is connected to the lower part of the swirling flow generating section 205.

[0047] The swirling flow generating section 205 includes: a fluid inflow section 250, which allows washing water to flow in from the inflow section 260 and swirl; and a cylindrical section 270, which is disposed above the fluid inflow section 250 and allows the swirling washing water to flow out toward the centrifugal separation section 204.

[0048] Figure 3 This is a schematic cross-sectional view showing the structure of the centrifuge 200 as viewed from below. (See attached image.) Figure 3 As shown, the fluid inlet 250 has an annular first circumferential wall 252, which has an inlet 285 for the inflow of washing water. Figure 2As shown, the inflow space 261 enclosed by the first peripheral wall portion 252 is provided with a bottom wall portion 251 that blocks the lower side (bottom side of the centrifuge 200) of the inflow space 261, and a counter wall portion 253 that is opposite to the bottom wall portion 251 in the vertical direction (direction of the rotation axis of the swirling flow). The counter wall portion 253 is connected to the lower end (fluid inflow portion 250 side) of the cylindrical portion 270. Within the inflow space 261 enclosed by the first peripheral wall portion 252, the bottom wall portion 251, and the counter wall portion 253, a fluid is generated along the... Figure 3 The swirling flow is shown in the direction of arrow A. In the following description, the upstream end of the swirling flow in the flow direction of the first circumferential wall 252 is referred to as the "upstream end 282". In the following description, the end of the first circumferential wall 252 on the side opposite to the upstream end 282 is referred to as the "downstream end 257". That is, it can also be said that the downstream end 257 is located downstream of the upstream end 282 along the first circumferential wall 252 in the flow direction of the swirling flow. The inlet 285 is formed as the space between the upstream end 282 and the downstream end 257.

[0049] The first peripheral wall portion 252 includes a first arcuate wall portion 255 and a second arcuate wall portion 254 that are continuously connected to each other. The first arcuate wall portion 255 is located downstream of the second arcuate wall portion 254 in the flow direction of the swirling flow indicated by arrow A.

[0050] The first arc-shaped wall portion 255 forms the downstream end 257 of the first peripheral wall portion 252, and extends from the downstream end 257 in a curved manner with a certain radius of curvature. The first arc-shaped wall portion 255 surrounds Figure 3 The circular space 256 shown is approximately half of the circular space 256. Furthermore, the circular space 256 has a center that coincides with the center of curvature of the first arcuate wall portion 255, and has a radius that is equal to the radius of curvature of the inner circumferential surface of the first arcuate wall portion 255.

[0051] The second arcuate wall portion 254 forms the upstream end 282 of the first peripheral wall portion 252 and is connected to the first arcuate wall portion 255. The second arcuate wall portion 254 has a larger radius of curvature than the first arcuate wall portion 255, and extends in a curved manner from the connection portion 258 of the second arcuate wall portion 254 and the first arcuate wall portion 255 toward the upstream end 282 with a gradually increasing radius of curvature.

[0052] At the connecting portion 258, the directions of the tangents on the inner peripheral surfaces of the second arcuate wall portion 254 and the first arcuate wall portion 255 are consistent with each other. Therefore, the inner peripheral surfaces of the second arcuate wall portion 254 and the first arcuate wall portion 255 are continuous. In addition, the direction of the tangent on the inner peripheral surface of the second arcuate wall portion 254 at the upstream end 282 is approximately parallel to the direction of the tangent on the circular space 256 at the formation position of the downstream end 257.

[0053] The second arc-shaped wall portion 254 bends with a larger radius of curvature than the first arc-shaped wall portion 255, thus forming a curved space 283 that bends along the outer periphery of the circular space 256 in the radial direction of the circular space 256. That is, the aforementioned inflow space 261 that generates the swirling flow is composed of the curved space 283 and the circular space 256.

[0054] The curved space 283, when viewed from below, has a shape that gradually narrows from the upstream end 282 of the second arcuate wall portion 254 toward the connection portion 258 of the second arcuate wall portion 254 and the first arcuate wall portion 255. The curved space 283 is provided so that the washing water flowing into the first peripheral wall portion 252 via the inlet 285 gradually merges with the swirling flow within the first peripheral wall portion 252.

[0055] The bottom wall portion 251 has a shape that combines the circular space 256 and the curved space 283 when viewed from below, and it completely closes the inflow space 261 of the fluid inflow portion 250. On the other hand, the opposing wall portion 253 has a shape identical to the curved space 283 when viewed from below. The opposing wall portion 253 is positioned opposite to the bottom wall portion 251 at the location where the curved space 283 is formed, and closes the curved space 283 on the side opposite to the side where the bottom wall portion 251 is located. Figure 2 As shown, the opposing wall portion 253 and the bottom wall portion 251, together with the upstream end 282 of the second arcuate wall portion 254 and the downstream end 257 of the first arcuate wall portion 255, form a rectangular entrance 285. That is, the entrance 285 is located radially outward from the circular space 256.

[0056] like Figure 3 As shown, the opposing wall portion 253 and the first arc-shaped wall portion 255 form a circular opening 284 coaxial with the circular space 256 on the upper side (cylindrical portion 270 side) of the fluid inlet portion 250. The washing water, which becomes a swirling flow within the fluid inlet portion 250, flows out of the fluid inlet portion 250 through the opening 284.

[0057] The inflow section 260 includes: an inner wall section 268 connected to the downstream end 257 of the first peripheral wall section 252 of the fluid inflow section 250; an outer wall section 267 connected to the upstream end 282 of the first peripheral wall section 252 of the fluid inflow section 250; an upper wall of the inflow section; and a lower wall of the inflow section. The inner wall section 268 extends toward the drain pipe 144 in the tangential direction of the circular space 256 at the downstream end 257 of the first peripheral wall section 252. The outer wall section 267 extends in the tangential direction of the second arcuate wall section 254 at the upstream end 282 of the first peripheral wall section 252. Since the tangential direction of the second arcuate wall section 254 at the upstream end 282 of the second arcuate wall section 254 is consistent with the tangential direction of the circular space 256 at the formation position of the downstream end 257, the outer wall section 267 extends parallel to the inner wall section 268. That is, the inflow section 260 is a flow path composed of the inner wall section 268, the outer wall section 267, the upper wall of the inflow section, and the lower wall of the inflow section.

[0058] A flexible hose component constituting a drainage pipe 144 is connected to the inlet 260. Therefore, the inlet 260 is formed such that its cross-sectional shape gradually changes from circular to rectangular in the range from the drainage pipe 144 to the inlet 285.

[0059] like Figure 2 As shown, the cylindrical portion 270 is formed by a second peripheral wall portion 271, which has a predetermined axial length and an inner diameter that gradually decreases from the lower end (cylindrical portion 270 side) of the housing 210 (described later) toward the upper end (cylindrical portion 270 side) of the fluid inlet portion 250. In other words, the second peripheral wall portion 271 of the cylindrical portion 270 is formed in a conical shape, with a larger inner diameter towards the upper side (centrifugal separation portion 204 side) and a smaller inner diameter towards the lower side (fluid inlet portion 250 side). Therefore, if the washing water swirling inside the cylindrical portion 270 reaches the vicinity of the upwardly extending and inclined second peripheral wall portion 271, a phenomenon such as... Figure 2 The swirling flow contains an upward component, as indicated by arrow C. Furthermore, the axial length of the cylindrical portion 270 is preferably at least 50% of the diameter of the inlet 285 (the axial dimension of the cylindrical portion 270), and more preferably at least 100%. This results in a swirling flow containing an upward component, creating a more stable and powerful flow.

[0060] Within the cylindrical portion 270, a columnar internal space 272 is formed by a conical second circumferential wall portion 271. At the lower end of the cylindrical portion 270 (on the fluid inlet portion 250 side), the inner diameter of the internal space 272 is equal to the diameter of the circular space 256, and the internal space 272 is coaxial with the circular space 256 of the fluid inlet portion 250. Furthermore, the inlet 285 of the fluid inlet portion 250 is located radially outward from the circular space 256 of the fluid inlet portion 250, thus the inlet 285 is located radially outward from the internal space 272. Therefore, the flow of washing water flowing in from the inlet 285 can smoothly merge with the washing water swirling within the circular space 256, generating a swirling flow along the first circumferential wall portion 252 of the fluid inlet portion 250. In addition, the swirling center of the swirling flow flowing within the fluid inlet portion 250 can be made approximately aligned with the central axis of the cylindrical portion 270 and the rotation axis of the rotating cylinder 220.

[0061] like Figure 2 As shown, the centrifugal separation unit 204 is configured to receive the swirling flow generated in the fluid inlet 250 and to separate foreign matter from the swirling flow. The centrifugal separation unit 204 includes a housing 210, a rotating cylinder 220 that rotates within the housing 210, and a pump unit 230 that draws up the swirling washing water in the fluid inlet 250 via the rotating cylinder 220.

[0062] The housing 210 is connected to the upper end of the cylindrical portion 270 (the centrifugal separation portion 204 side), and the internal space of the housing 210 is connected to the circular space 256 in the fluid inflow portion 250 via the internal space 272 of the cylindrical portion 270.

[0063] The housing 210 includes: a cylindrical receiving portion 211 connected to the upper end of the cylindrical portion 270; and a pump receiving portion 212 connected to the cylindrical receiving portion 211 on the side opposite to the cylindrical portion 270. The cylindrical receiving portion 211 is a cylindrical portion having an inner diameter larger than that of the cylindrical portion 270. The pump receiving portion 212 is a disc-shaped portion forming an internal space opening towards the cylindrical receiving portion 211. The pump receiving portion 212 includes: a cylindrical third peripheral wall portion 213; and an end wall portion 214 that closes the internal space enclosed by the third peripheral wall portion 213 on the side opposite to the cylindrical receiving portion 211. Figure 1 As shown, a spray pipe 216 is connected to the third peripheral wall portion 213, which is used to allow the washing water in the pump housing portion 212 to flow to the return pipe 145.

[0064] The rotating drum 220 is provided to rotate within the drum housing 211 and to centrifugally separate foreign matter contained in the washing water swirling within the rotating drum 220. The rotating drum 220 is arranged coaxially within the drum housing 211 of the housing 210 with the circular space 256 of the fluid inlet 250 and the internal space 272 of the cylindrical section 270. Figure 2 As indicated by arrow B, a gap is formed between the outer peripheral surface 225 of the housing 210 and the rotating cylinder 220 to connect the pump housing 212 and the cylindrical portion 270.

[0065] The rotating cylinder 220 includes a fourth circumferential wall portion 221, an annular plate portion 222, and an annular plate portion 223. The annular plate portion 222 protrudes radially inward from the end of the fourth circumferential wall portion 221 on the cylindrical portion 270 side. The annular plate portion 223 protrudes radially inward from the end of the fourth circumferential wall portion 221 on the pump housing portion 212 side. The inner circumferential surface of the fourth circumferential wall portion 221 is the portion where foreign matter separated by centrifugation adheres.

[0066] The annular plate portion 222 is provided to increase the contact area between the rotating drum 220 and the washing water flowing into the drum receiving portion 211. That is, by providing the annular plate portion 222, the rotational force transmitted by the rotating drum 220 to the washing water in the drum receiving portion 211 can be increased. The opening of the annular plate portion 222 is formed coaxially with the cylindrical portion 270 so that the washing water, which has become a swirling flow in the circular space 256 within the fluid inflow portion 250, flows into the rotating drum 220 via the cylindrical portion 270.

[0067] The annular plate portion 223 is provided to prevent foreign matter adhering to the fourth peripheral wall portion 221 from flowing out into the pump receiving portion 212. Additionally, similar to the annular plate portion 222, the annular plate portion 223 serves to increase the rotational force transmitted by the rotating drum 220 to the washing water in the drum receiving portion 211. The central opening of the annular plate portion 223 is provided to allow the washing water in the rotating drum 220 to flow out into the pump receiving portion 212.

[0068] like Figure 2 As shown, the pump section 230 includes: a plurality of pump blades 231 integrally formed with respect to the outer surface of the annular plate section 223 facing the pump housing section 212; and a mounting plate section 232 connected to the pump blades 231 on the side opposite to the side where the annular plate section 223 is located.

[0069] like Figure 3As shown, multiple pump blades 231 are arranged radially within the pump housing 212. In the pump section 230, the rotation of the multiple pump blades 231 creates a pressure difference between the rotating cylinder 220 side and the ejector pipe 216 side of the pump section 230. Consequently, washing water in the rotating cylinder 220 is drawn into the pump housing 212, and the washing water in the pump section 230 is ejected into the ejector pipe 216. Here, the direction of rotation of the pump blades 231 as the washing water flows from the rotating cylinder 220 through the pump housing 212 to the ejector pipe 216 is referred to as the "forward rotation direction".

[0070] Mounting plate 232 is provided to transmit the driving force of drive unit 240 to rotating cylinder 220 and multiple pump blades 231.

[0071] The drive unit 240 is composed of an electric motor. That is, the drive unit 240 includes: an electric motor body 241, which is disposed on the outside of the housing 210; and a drive shaft 242, which protrudes from the electric motor body 241 into the pump receiving portion 212 of the housing 210 and is connected to the mounting plate portion 232. The electric motor body 241 is configured to be controlled by the control unit 170 to make the drive shaft 242 rotate in the forward direction.

[0072] (Description of the action)

[0073] The operation of the washing machine 100 will be described below. As described below, the washing machine 100 performs the washing process, rinsing process, and spin-drying process sequentially under the control of the control unit 170.

[0074] When the washing process begins, the control unit 170 controls the water supply valve 131 and the drain valve 142, opening the water supply path 130 and closing the drain path 140. When the water supply valve 131 opens the water supply path 130, washing water flows within the water supply path 130 and into the detergent tank 132. The washing water dissolves detergent in the detergent tank 132 and flows out of the detergent tank 132. Afterwards, the detergent-containing washing water flows into the water tank 112 through the water inlet 116. At this time, the drain valve 142 is closed, so the washing water accumulates in the water tank 112.

[0075] When a predetermined amount of washing water accumulates in the water tank 112, the control unit 170 controls the drive unit 121 to rotate the rotating drum 120 and the protrusion 123. As a result, the laundry 101 is agitated and washed inside the rotating drum 120.

[0076] During the washing of the laundry 101 within the rotating drum 120, a centrifugal separation process for foreign matter is performed by the centrifuge 200. Specifically, the control unit 170 controls the drive unit 240 of the centrifuge 200, causing the pump unit 230 and the rotating drum 220 of the centrifuge 200 to rotate in the forward direction. Driven by the rotation of the pump unit 230, the washing water in the water tank 112 flows out through the outlet 117 of the water tank 112 into the drain pipe 144. This washing water contains foreign matter such as fibers and sebum separated from the laundry 101 during the washing process. The washing water containing foreign matter flows into the inlet 260 of the centrifuge 200 through the drain pipe 144. The washing water in the inlet 260 passes sequentially through the drain pipe 144 and the inlet 285.

[0077] Washing water flows into the curved space 283 through inlet 285. In the curved space 283, the washing water flows along the inner circumferential surface of the second arcuate wall 254 and into the circular space 256. The washing water flowing into the circular space 256 flows along the inner circumferential surface of the first arcuate wall 255. Thus, the flow along the inner circumferential surfaces of the second arcuate wall 254 and the first arcuate wall 255 results in the generation of a swirling flow in the fluid inlet 250.

[0078] The washing water, which forms a swirling flow within the fluid inlet 250, is drawn up by the suction force of the pump 230 and flows into the cylindrical section 270. The cylindrical section 270 is coaxial with the circular space 256 and has an inner diameter at its lower end (on the fluid inlet 250 side) equal to the diameter of the circular space 256. Therefore, the washing water flows into the cylindrical section 270 while maintaining a swirling flow state generated within the circular space 256. Then, the swirling flow flows into the rotating cylinder 220 through the cylindrical section 270. At this time, the opening at the center of the annular plate 222 of the rotating cylinder 220 is coaxial with the cylindrical section 270, allowing the washing water to flow into the rotating cylinder 220 while maintaining a swirling flow.

[0079] At this time, since the rotating drum 220 is driven to rotate by the drive unit 240, the rotational force of the rotating drum 220 is transmitted to the washing water that forms a swirling flow. As a result of the rotational force of the rotating drum 220 being transmitted to the washing water, the angular velocity of the swirling flow increases, and the centrifugal force acting on the foreign matter contained in the swirling flow increases. Therefore, under the action of centrifugal force, the foreign matter moves towards the fourth circumferential wall portion 221 of the rotating drum 220 and is pressed against the fourth circumferential wall portion 221. As a result, the washing water inside the rotating drum 220 is in a state where the foreign matter is centrifugally separated.

[0080] When the rotating drum 220 is driven to rotate, the washing water is pressurized by the pump section 230. As a result, the pressure of the washing water at the nozzle 215 of the pump housing 212 is greater than the pressure of the washing water at the opening 219 at the lower end of the housing 210. Due to this pressure difference, a portion of the washing water flowing from the rotating drum 220 toward the nozzle 215 may sometimes flow backward through the opening 219 from between the outer peripheral surface 225 of the housing 210 and the rotating drum 220 into the internal space 272 of the cylindrical section 270. This backward-flowing washing water into the internal space 272 may merge with the swirling flow of the cylindrical section 270 and further flow backward, causing turbulence in the swirling flow. However, this backward-flowing washing water into the internal space 272 will be guided back toward the rotating drum 220 by the swirling flow containing an upward component within the internal space 272, and will not flow into the circular space 256 of the fluid inlet section 250. In other words, even if the flow of the swirling flow inside the cylindrical section 270 is disturbed by the countercurrent washing water, the countercurrent washing water, which becomes part of the swirling washing water, will at least not flow into the circular space 256. A swirling flow can be generated in the fluid inlet section 250 without disturbing the swirling of the washing water.

[0081] Furthermore, the inlet 285 of the fluid inlet section 250 is formed on the outside of the circular space 256. Therefore, the incoming washing water is less susceptible to the influence of backflowing washing water, and a swirling flow can be generated in the fluid inlet section 250 without causing turbulence in the inflow of washing water. Moreover, the swirling center of the swirling flow flowing in the fluid inlet section 250 can be approximately aligned with the central axis of the cylindrical section 270 and the rotation axis of the rotating cylinder 220, allowing the washing water to flow into the cylindrical section 270 while maintaining the swirling flow.

[0082] The washing water from which foreign matter has been separated by centrifugation flows into the pump housing 212 through the opening of the annular plate portion 223 under the suction force of the pump section 230. At this time, the foreign matter pressed against the fourth circumferential wall portion 221 of the rotating cylinder 220 is also subject to the suction force of the pump section 230, but the annular plate portion 223 prevents the foreign matter from flowing into the pump housing 212.

[0083] Washing water flowing into the pump housing 212 is ejected from the pump section 230 and flows into the return line 145 through the ejection pipe 216 connected to the pump housing 212. The washing water returns to the water tank 112 through the return line 145. That is, the centrifuge 200 can return the washing water, after removing foreign matter, to the water tank 112.

[0084] During the aforementioned washing process, the washing machine 100 may also perform an intermediate spin-drying process (the spin-drying process performed during the washing process). At this time, the control unit 170 controls the drain valve 142 to open the discharge path 140. In addition, the control unit 170 controls the drive unit 121 to increase the rotational speed of the rotating drum 120, thereby centrifugally separating the water contained in the laundry 101.

[0085] During the intermediate dehydration process, the control unit 170 controls the drive unit 240 of the centrifuge 200 to stop the pump unit 230 and the rotating drum 220. As a result, the centrifugal force acting on the foreign matter disappears, making it easier to peel off the foreign matter adhering to the fourth circumferential wall portion 221 of the rotating drum 220.

[0086] The control unit 170 opens the discharge path 140, causing the washing water to flow in the opposite direction to the centrifugal separation process performed by the centrifugal separator 200 on foreign objects. That is, the washing water inside the housing 210, along with the foreign objects detached from the fourth circumferential wall portion 221 of the rotating drum 220, passes sequentially under gravity through the cylindrical portion 270, the fluid inlet portion 250, the inlet portion 260, and the drain pipe 144. Then, the washing water and foreign objects that have passed through the drain pipe 144 can be discharged to the outside of the washing machine 100 through the discharge path 140.

[0087] In the rinsing process, similar to the washing process, a predetermined amount of water is controlled to accumulate in the water tank 112. After the predetermined amount of water has accumulated in the water tank 112, the drive unit 121 for the rotating drum 120 is controlled by the control unit 170 to agitate the laundry 101 inside the rotating drum 120. After agitating the laundry 101 for a time sufficient to remove detergent from it, the control unit 170 controls the drain valve 142 to open the discharge path 140. Furthermore, during the rinsing process, the same intermediate dehydration process as performed in the washing process can also be performed. In addition, during the rinsing process, the centrifugal separation process performed by the centrifuge 200 can be performed, similar to the washing process.

[0088] After the rinsing process, the control unit 170 controls the drive unit 121 for the rotating drum 120 to cause the washing machine 100 to perform a spin-drying process. During the spin-drying process, the control unit 170 controls the drive unit 121 to make the rotational speed of the rotating drum 120 higher than the rotational speed of the rotating drum 120 during the washing and rinsing processes. As a result, water is centrifugally separated from the laundry 101 in the rotating drum 120.

[0089] In this centrifuge 200, the second circumferential wall 271 of the cylindrical section 270 is formed as a cone with a larger inner diameter towards the upper side (centrifugal separation section 204 side) and a smaller inner diameter towards the lower side (fluid inflow section 250 side). Therefore, if the washing water swirling inside the cylindrical section 270 reaches the vicinity of the upwardly inclined second circumferential wall 271, a phenomenon such as... will occur near the second circumferential wall 271. Figure 2 As indicated by arrow C, a swirling flow containing an upward component is generated. Specifically, when the rotating cylinder 220 is driven to rotate, near the second circumferential wall 271, the second circumferential wall 271 of the cylindrical portion 270 exerts an upward force (towards the centrifugal separation section 204) on the washing water that is subjected to centrifugal force acting radially outwards from the cylindrical portion 270 through swirling. This generates a swirling flow near the second circumferential wall 271 containing an upward component along the second circumferential wall 271.

[0090] Therefore, for the centrifuge 200, even when the washing water flows back from between the outer peripheral surface 225 of the shell 210 and the rotating drum 220 to the cylindrical section 270, an upward force can be applied to the backflowing washing water near the second peripheral wall section 271. As a result, the centrifuge 200 can suppress the inflow of backflowing washing water from the cylindrical section 270 to the fluid inflow section 250. Consequently, for the centrifuge 200, a swirling flow can be generated in the swirling flow generation section 205 without causing turbulence in the swirling of the washing water.

[0091] Furthermore, in the fluid inlet section 250, an inlet 285 and a curved space 283 are provided on the outer side of the circular space 256. Washing water flowing in from the inlet section 260 through the inlet 285 flows into the curved space 283 before flowing into the circular space 256. The curved space 283 gradually narrows in the downstream direction of the flow direction of the swirling flow within the fluid inlet section 250. Therefore, the washing water flowing into the curved space 283 gradually merges with the washing water swirling in the circular space 256. As a result, a swirling flow along the first circumferential wall 252 of the fluid inlet section 250 can be generated, and the swirling center of the swirling flow flowing within the fluid inlet section 250 can be made to approximately coincide with the central axis of the cylindrical section 270 and the rotation axis of the rotating cylinder 220. Therefore, even when the washing water flows back from between the housing 210 and the rotating cylinder 220 to the cylindrical section 270, the washing water flowing in from the inlet section 260 is not easily affected, and the swirling flow within the circular space 256 is not easily disturbed.

[0092] In addition, various modifications or improvements can be made to the washing machine 100 of the first embodiment. Figure 4 This is a cross-sectional view that schematically shows the structure of a modified centrifuge 200 of the first embodiment as viewed from below. Additionally, Figure 5A and Figure 5BThese are longitudinal sectional views showing the structure of a centrifuge 200 according to other variations of the first embodiment.

[0093] For example, to achieve miniaturization and weight reduction of the centrifuge 200, a tortuous space 283 may not be formed within the fluid inflow section 250. That is, as... Figure 4 As shown, the first peripheral wall 252 of the fluid inflow section 250 is formed as an arc with a certain radius of curvature extending from the upstream end 282 towards the downstream end 257. In this case, the inflow space 261 is formed to coincide with the circular space 256 and is surrounded by the arc-shaped first peripheral wall 252. The inlet 285 of the fluid inflow section 250 is located inside the circular space 256.

[0094] Furthermore, the second circumferential wall portion 271 is tapered, extending from the lower end (cylindrical portion 270 side) of the housing 210 toward the upper end (cylindrical portion 270 side) of the fluid inflow portion 250, with its inner diameter gradually decreasing, but it is not limited to this. For example, it could also be, as... Figure 5A As shown, the second peripheral wall portion 271 includes a cylindrical portion 274 and a conical portion 273. The cylindrical portion 274 is formed by extending vertically downward from the lower end of the housing 210 to the middle portion of the second peripheral wall portion 271. The conical portion 273 is formed by extending from the lower side (fluid inlet portion 250 side) of the cylindrical portion 274 toward the upper end of the fluid inlet portion 250, with its inner diameter gradually decreasing. As a result, an upward force is exerted on the swirling washing water near the conical portion 273. Therefore, for the centrifuge 200 of this modified example, even when the washing water flows back into the cylindrical portion 270 through the space between the housing 210 and the rotating drum 220, the inflow of backflowing washing water from the cylindrical portion 270 to the fluid inlet portion 250 can be suppressed.

[0095] Or, it could be, such as Figure 5B As shown, the second peripheral wall portion 271 includes a conical portion 273 and two cylindrical portions 274 and 275. The two cylindrical portions 274 and 275 are respectively connected to the lower end (cylindrical portion 270 side) of the housing 210 and the upper end (cylindrical portion 270 side) of the fluid inlet portion 250. The conical portion 273 connects the two cylindrical portions 274 and 275. The conical portion 273 extends from the cylindrical portion 274 connected to the lower end of the housing 210 toward the cylindrical portion 275 connected to the upper end of the fluid inlet portion 250, with its inner diameter gradually decreasing. Therefore, an upward force is exerted on the swirling washing water near the conical portion 273. Therefore, for the centrifuge 200 of this modified example, even when the washing water flows back into the cylindrical portion 270 through the space between the housing 210 and the rotating drum 220, the inflow of the backflowing washing water from the cylindrical portion 270 into the fluid inflow portion 250 can be suppressed.

[0096] Furthermore, the centrifuge 200 is mounted inside the washing machine 100 with the axis of rotation of the swirling flow approximately vertical, but is not limited to this. For example, the centrifuge 200 may also be mounted inside the washing machine 100 with the axis of rotation of the swirling flow approximately horizontal.

[0097] A centrifuge 200 according to one aspect of the first embodiment is configured to separate foreign matter contained in washing water (an example of the liquid fluid of the present invention). The centrifuge 200 includes: a drive unit 240 that generates driving force; a centrifugal separation unit 204; and a swirling flow generating unit 205 connected to the centrifugal separation unit 204. The centrifugal separation unit 204 has a housing 210 and a rotating drum 220 disposed within the housing 210 and rotated by the driving force of the drive unit 240. The centrifugal separation unit 204 centrifuges away foreign matter from the washing water within the rotating drum 220. The swirling flow generating unit 205 includes a fluid inflow section 250 and a cylindrical section 270. The fluid inlet 250 has a first peripheral wall 252, which has an inlet 285 for allowing washing water to flow in, and guides the washing water flowing into the inflow space 261 inside the first peripheral wall 252 in a swirling manner. A cylindrical portion 270 is located between the fluid inlet 250 and the centrifugal separator 204, causing the washing water swirling in the fluid inlet 250 to swirl and be introduced into the centrifugal separator 204. The cylindrical portion 270 includes a second peripheral wall 271, in which at least a portion of the cylindrical portion 270 in the axial direction is formed as a cone with a diameter that gradually decreases from the housing 210 toward the fluid inlet 250.

[0098] According to the above structure, the conical second peripheral wall 271 is used to exert an upward force (towards the centrifugal separation section 204) on the washing water that is subjected to centrifugal force acting radially outwards towards the cylindrical section 270 through swirling. As a result, a swirling flow containing an upward component along the conical second peripheral wall 271 is generated near the conical second peripheral wall 271. Therefore, for the centrifuge 200 of the first embodiment, even when the washing water in the centrifugal separation section 204 flows back towards the cylindrical section 270 from between the outer peripheral surface 225 of the housing 210 and the rotating drum 220, an upward force (towards the centrifugal separation section 204) can be exerted on the backflowing washing water. Thus, the centrifuge 200 of the first embodiment can suppress the backflowing washing water from the cylindrical section 270 into the fluid inlet section 250. As a result, for the centrifuge 200 of the first embodiment, a swirling flow can be generated in the fluid inlet section 250 without causing turbulence in the swirling of the washing water. That is, the centrifuge 200 of the first embodiment can suppress the reduction of the centrifugal force acting on foreign matter by the centrifugal separation section 204.

[0099] In the above structure, the inlet 285 of the fluid inflow section 250 may be defined as the space between the upstream end 282 and the downstream end 257. The upstream end 282 is located on the upstream side of the first peripheral wall portion 252 in the flow direction of the swirling flow. The downstream end 257 is located on the side opposite to the side where the upstream end 282 is located in the flow direction of the swirling flow. Alternatively, the first peripheral wall portion 252 may have a first arcuate wall portion 255 and a second arcuate wall portion 254. The first arcuate wall portion 255 bends from the downstream end 257 with a predetermined radius of curvature. The second arcuate wall portion 254 bends arcuately from the upstream end 282 with a radius of curvature larger than the predetermined radius of curvature and extends therefrom, and is connected to the first arcuate wall portion 255. Alternatively, the second arcuate wall portion 254 may be located radially outward from the second peripheral wall portion 271 of the cylindrical portion 270.

[0100] According to the above structure, the inlet 285 of the fluid inflow section 250 is formed by the first arcuate wall portion 255 and the second arcuate wall portion 254 at a position radially outer than the second peripheral wall portion 271 of the cylindrical portion 270. Therefore, for the centrifuge 200 of the first embodiment, even when the washing water flows back from between the housing 210 and the rotating drum 220 to the cylindrical portion 270, the inlet 285 of the fluid inflow section 250 is not easily affected. As a result, for the centrifuge 200 of the first embodiment, a swirling flow can be generated in the fluid inflow section 250 without causing turbulence in the swirling of the washing water.

[0101] Another aspect of the above-described embodiment of the washing machine 100 includes: the centrifuge 200 described above; and a washing tub 115, which washes the laundry 101. The centrifuge 200 is connected to the washing tub 115 such that washing water in the washing tub 115 flows into the centrifuge 200.

[0102] According to the above structure, in the washing machine 100 of the first embodiment, the reduction of the centrifugal force acting on foreign matter in the centrifugal separator 204 of the centrifugal separator 200 of the first embodiment can be suppressed, thus enabling effective separation of foreign matter contained in the washing water in the centrifugal separator 200. Furthermore, in the washing machine 100 of the first embodiment, the re-adhesion of separated foreign matter to the laundry 101 can be suppressed, thereby improving the cleaning effect.

[0103] (Second Implementation)

[0104] Figure 6This is a longitudinal sectional view schematically showing the structure of the centrifuge 200 according to the second embodiment. In the first embodiment, when washing water flows back into the cylindrical portion 270 through the space between the housing 210 and the rotating drum 220, the flow of backflowing washing water from the cylindrical portion 270 to the fluid inflow portion 250 is suppressed by the second peripheral wall portion 271, which is formed in a conical shape. In the centrifuge 200 of the second embodiment, by providing an inflow prevention portion 290 in the swirling flow generating portion 205, the flow of backflowing washing water from the cylindrical portion 270 to the fluid inflow portion 250 is suppressed more effectively. In addition to the swirling flow generating portion 205, Figure 6 The centrifuge 200 of the second embodiment shown is constructed in accordance with... Figure 2 The centrifuge 200 of the first embodiment shown has the same structure.

[0105] like Figure 6 As shown, the cylindrical portion 270 is formed such that the inner diameter of its lower end (fluid inflow portion 250 side) is larger than the diameter of the circular space 256 of the fluid inflow portion 250. Furthermore, the opposing wall portion 253 of the fluid inflow portion 250 is formed to cover the upper side (cylindrical portion 270 side) of the curved space 283, extending radially inward from the lower end (fluid inflow portion 250 side) of the second circumferential wall portion 271 of the cylindrical portion 270 towards the circular space 256. That is, the portion of the opposing wall portion 253 that overlaps with the inner space 272 of the cylindrical portion 270 and the curved space 283 of the fluid inflow portion 250 in the top view functions as an inflow prevention portion 290 separating the inner space 272 and the curved space 283. At this time, the inflow prevention portion 290 of the opposing wall portion 253 is configured to protrude radially inward from the lower end (fluid inflow portion 250 side) of the cylindrical portion 270.

[0106] Since the inflow prevention section 290 separates the internal space 272 and the curved space 283, even when the washing water flows back from the centrifugal separation section 204 to the cylindrical section 270, the inflow of backflow washing water from the internal space 272 of the cylindrical section 270 to the fluid inflow section 250 can be effectively suppressed. Therefore, the centrifugal separator 200 of the second embodiment can suppress the turbulence of the swirling flow caused by the backflow washing water flowing into the cylindrical section 270. As a result, a swirling flow can be generated in the fluid inflow section 250 without causing turbulence in the swirling of the washing water.

[0107] Similar to the first embodiment, the centrifuge 200 of one aspect of the second embodiment is configured to separate foreign matter contained in washing water (an example of the liquid fluid of the present invention). The centrifuge 200 includes: a drive unit 240 that generates driving force; a centrifugal separation unit 204; and a swirling flow generating unit 205 connected to the centrifugal separation unit 204. The centrifugal separation unit 204 has a housing 210 and a rotating drum 220 disposed within the housing 210 and rotated by the driving force of the drive unit 240. The centrifugal separation unit 204 centrifuges separates foreign matter from the washing water within the rotating drum 220. The swirling flow generating unit 205 includes a fluid inflow section 250 and a cylindrical section 270. The fluid inlet 250 has a first peripheral wall 252, which has an inlet 285 for allowing washing water to flow in, and guides the washing water flowing into the inflow space 261 inside the first peripheral wall 252 in a swirling manner. A cylindrical portion 270 is located between the fluid inlet 250 and the centrifugal separator 204, causing the washing water swirling in the fluid inlet 250 to swirl and be introduced into the centrifugal separator 204. The cylindrical portion 270 includes a second peripheral wall 271, in which at least a portion of the cylindrical portion 270 in the axial direction is formed as a cone with a diameter that gradually decreases from the housing 210 toward the fluid inlet 250.

[0108] In the above structure, similar to the first embodiment, the first peripheral wall portion 252 of the fluid inflow portion 250 may also include a first arcuate wall portion 255 and a second arcuate wall portion 254. The first arcuate wall portion 255 is formed as an arc concentric with the drive shaft 242 of the drive portion 240. The second arcuate wall portion 254 has a radius of curvature larger than that of the first arcuate wall portion 255 and extends from the upstream end of the first arcuate wall portion 255 in the direction of rotation to the inlet 285. The second arcuate wall portion 254 may also be configured to be located radially outward from the second peripheral wall portion 271 of the cylindrical portion 270.

[0109] In the above structure, the swirling flow generating section 205 may also include an inflow prevention section 290, which prevents at least a portion of the washing water swirling in the cylindrical section 270 from flowing into the fluid inflow section 250.

[0110] According to the above structure, the cylindrical portion 270 of the swirling flow generating section 205 is provided with an inflow prevention section 290 to prevent washing water from flowing from the cylindrical portion 270 into the fluid inflow section 250. Therefore, for the centrifuge 200 of the second embodiment, even when washing water flows back from the centrifugal separation section 204 into the cylindrical portion 270, the inflow of backflow washing water from the cylindrical portion 270 into the fluid inflow section 250 can be suppressed.

[0111] In the above structure, the inflow prevention part 290 may also protrude inward from the end of the cylindrical part 270 on the fluid inflow part 250 side of the cylindrical part 270 at least on the side of the cylindrical part 270 of the inlet 285.

[0112] According to the above structure, the inflow prevention portion 290, which is formed to protrude radially inward from the lower end of the cylindrical portion 270, can be used to suppress the inflow of backflow washing water from the cylindrical portion 270 to the fluid inflow portion 250.

[0113] Similar to the first embodiment, the washing machine 100 of another aspect of the above-described embodiment includes: the centrifuge 200 of the second embodiment; and a washing tub 115 for washing the laundry 101. The centrifuge 200 of the second embodiment is connected to the washing tub 115 such that the washing water in the washing tub 115 flows into the centrifuge 200 of the second embodiment.

[0114] In the first and second embodiments, the centrifuge 200 is mounted on a rotary drum washing machine 100 for centrifugally separating foreign matter (fibers, etc.) separated from the laundry 101. Alternatively, the centrifuge 200 may be mounted on a vertical washing machine. Alternatively, the centrifuge 200 is not limited to various washing machines and can also be applied to devices for cleaning bathwater or organic wastewater.

[0115] (Effects, etc.)

[0116] The centrifuge 200 and washing machine 100 of the above embodiments have the following features and achieve the following effects.

[0117] One aspect of the centrifugal separation mechanism described above separates foreign matter contained in a liquid fluid. The centrifugal separator includes: a drive unit that generates driving force; a centrifugal separation unit having a housing and a rotating cylinder disposed within the housing and rotated by the driving force of the drive unit, the centrifugal separation unit centrifugally separating foreign matter from the fluid within the rotating cylinder; and a swirling flow generating unit connected to the centrifugal separation unit. The swirling flow generating unit includes a fluid inlet and a cylindrical section. The fluid inlet has a first circumferential wall portion having an inlet for fluid inflow, and the first circumferential wall portion guides the fluid in a manner that causes the fluid flowing into the inflow space inside the first circumferential wall portion to swirl. The cylindrical section is located between the fluid inlet and the centrifugal separation unit, causing the fluid swirling in the fluid inlet to swirl and be introduced into the centrifugal separation unit. The cylindrical section includes a second circumferential wall portion, in which at least a portion of the cylindrical section in the axial direction is formed as a cone shape whose diameter gradually decreases from the housing towards the fluid inlet.

[0118] According to the above structure, the conical second peripheral wall portion exerts an upward force (towards the centrifugal separation section) on the fluid that is exerting centrifugal force radially outward towards the cylindrical portion through swirling. As a result, a swirling flow containing an upward component along the conical second peripheral wall portion is generated near the conical second peripheral wall portion. Therefore, for the centrifuge of one aspect of the above embodiment, even when the fluid in the centrifugal separation section flows counter-currently from between the outer peripheral surface of the shell and the rotating cylinder towards the cylindrical portion, an upward force (towards the centrifugal separation section) can be exerted on the counter-current fluid. Therefore, the centrifuge of one aspect of the above embodiment can suppress the flow of counter-current fluid from the cylindrical portion into the fluid inlet portion. As a result, for the centrifuge of one aspect of the above embodiment, a swirling flow can be generated in the fluid inlet portion without causing turbulence in the fluid swirling. That is, the centrifuge of one aspect of the above embodiment can suppress the reduction of the centrifugal force acting on foreign matter in the centrifugal separation section.

[0119] In the above structure, the inlet of the fluid inflow section may also be defined as the space between the upstream end of the first circumferential wall section located on the upstream side in the flow direction of the swirling flow and the downstream end of the first circumferential wall section located on the side opposite to the upstream end in the flow direction of the swirling flow. Alternatively, the first circumferential wall section may have a first arc-shaped wall section and a second arc-shaped wall section, the first arc-shaped wall section being curved from the downstream end with a predetermined radius of curvature, and the second arc-shaped wall section being curved and extending from the upstream end with a radius of curvature larger than the predetermined radius of curvature, and connected to the first arc-shaped wall section. Furthermore, the second arc-shaped wall section may be configured to be located radially outward from the second circumferential wall section of the cylindrical section.

[0120] According to the above structure, the inlet of the fluid inlet is formed by the first and second arc-shaped walls at a radially outer position compared to the second circumferential wall of the cylindrical section. Therefore, for the centrifuge of one aspect of the above embodiment, a swirling flow along the first circumferential wall of the fluid inlet can be generated, and the center of swirling flow flowing within the fluid inlet can be substantially aligned with the central axis of the cylindrical section and the axis of rotation of the rotating cylinder. As a result, for the centrifuge of one aspect of the above embodiment, even when the fluid flows counter-currently from between the shell and the rotating cylinder towards the cylindrical section, a swirling flow can be generated in the fluid inlet without causing turbulence in the fluid swirling.

[0121] In the above structure, the swirling flow generating section may also include an inflow prevention section that prevents a portion of the fluid swirling inside the cylindrical section from flowing into the fluid inflow section.

[0122] According to the above structure, the cylindrical portion of the swirling flow generating section is provided with an inflow prevention section to prevent fluid from flowing from the cylindrical portion into the fluid inflow section. Therefore, for the centrifuge of one aspect of the above embodiment, even when the fluid flows back from the centrifugal separation section to the cylindrical portion, the inflow of the backflowing fluid from the cylindrical portion into the fluid inflow section can be suppressed.

[0123] In the above structure, the inflow prevention part may also protrude inward from the end of the cylindrical part on the fluid inflow side of the cylindrical part at least on the inlet cylindrical part side.

[0124] According to the above structure, the inflow prevention portion, which is formed to protrude radially inward from the lower end of the cylindrical portion, can be used to suppress the inflow of backflow fluid from the cylindrical portion to the fluid inflow portion.

[0125] Another aspect of the above-described embodiments of the washing machine includes: the centrifugal separator described above; and a washing tub for washing laundry. The centrifugal separator is connected to the washing tub in such a way that fluid from the washing tub flows into the centrifugal separator.

[0126] According to the above structure, in the washing machine of another aspect of the above embodiment, the reduction of the centrifugal force acting on foreign matter in the centrifugal separator can be suppressed, thus enabling effective separation of foreign matter contained in the fluid within the centrifugal separator. Furthermore, in the washing machine of another aspect of the above embodiment, the re-adhesion of separated foreign matter to the laundry can be suppressed, thereby improving the cleaning effect.

[0127] Industrial availability

[0128] This invention is suitable for various devices used to remove foreign matter from fluids.

[0129] Explanation of reference numerals in the attached figures

[0130] 100. Washing machine; 101. Laundry; 102. Faucet; 110. Outer casing; 111. Door; 112. Water tank; 113. Sealing component; 114. Suspension mechanism; 115. Washing tub; 116. Water inlet; 117. Drain outlet; 118. Inlet; 120. Rotating drum; 121. Drive unit; 123. Protrusion; 124. Small hole; 130. Water supply path; 131. Water supply valve; 132. Detergent tank; 139. Water supply unit; 140. Discharge path; 142. Drain valve; 143. Circulation Path; 144. Drainage pipe; 145. Return pipe; 170. Control unit; 200. Centrifuge; 204. Centrifugal separation unit; 205. Cyclone generation unit; 210. Shell; 211. Cylinder housing; 212. Pump housing; 213. Third peripheral wall; 214. End wall; 215. Spray outlet; 216. Spray pipe; 219. Opening; 220. Rotating cylinder; 221. Fourth peripheral wall; 222. Annular plate; 223. Annular plate; 225. Outer peripheral surface; 230. Pump unit; 231. Pump blades 232. Mounting plate; 240. Drive unit (driven unit of a centrifuge); 241. Motor body; 242. Drive shaft; 250. Fluid inlet; 251. Bottom wall; 252. First peripheral wall; 253. Opposite wall; 254. Second arc-shaped wall; 255. First arc-shaped wall; 256. Circular space; 257. Downstream end; 258. Connecting part; 260. Inlet; 261. Inlet space; 267. Outer wall; 268. Inner wall; 270. Cylindrical part; 271. Second peripheral wall 272. Internal space; 273. Conical part; 274. Cylindrical part; 275. Cylindrical part; 282. Upstream end; 283. Bend space; 284. Opening; 285. Inlet; 290. Inflow prevention part; 300. Centrifugal separator; 310. Centrifugal separation part; 311. Rotating cylinder; 312. Pump part; 315. Spray outlet; 320. Swirl flow generation part; 321. Inlet; 322. Peripheral wall part; 330. Inlet pipe; 340. Shell; 345. Opening; 350. Drive part.

Claims

1. A centrifugal separator for separating foreign matter contained in a liquid fluid, wherein, This centrifuge features: The drive unit generates driving force; A centrifugal separation unit has a housing and a rotating cylinder disposed within the housing and rotated by the driving force of the drive unit, the centrifugal separation unit centrifugally separating foreign matter from the fluid within the rotating cylinder; as well as A swirling flow generating section, which is integrated with the centrifugal separation section. The swirling flow generating section includes a fluid inlet section and a cylindrical section. The fluid inlet section has a first circumferential wall section with an inlet for the fluid to flow in. The first circumferential wall section guides the fluid flowing into the inflow space inside the first circumferential wall section in a swirling manner. The cylindrical section is located between the fluid inlet section and the centrifugal separation section, causing the fluid swirling in the fluid inlet section to swirl and be introduced into the centrifugal separation section. The cylindrical portion includes a second circumferential wall portion, in which at least a portion of the cylindrical portion in the axial direction is formed as a cone with a diameter that gradually decreases from the housing toward the fluid inflow portion.

2. The centrifuge according to claim 1, wherein, The inlet of the fluid inflow section is defined as the space between the upstream end of the first circumferential wall section located on the upstream side in the flow direction of the swirling flow and the downstream end of the first circumferential wall section located on the side opposite to the upstream end in the flow direction of the swirling flow. The first peripheral wall portion has a first arc-shaped wall portion and a second arc-shaped wall portion. The first arc-shaped wall portion bends from the downstream end with a predetermined radius of curvature, and the second arc-shaped wall portion bends in an arc shape from the upstream end with a radius of curvature larger than the predetermined radius of curvature and extends therefrom, and is connected to the first arc-shaped wall portion. The centrifugal separation mechanism is such that the second arc-shaped wall portion is located radially outward from the second peripheral wall portion of the cylindrical portion.

3. The centrifuge according to claim 1 or 2, wherein, The swirling flow generating section includes an inflow prevention section that prevents at least a portion of the fluid swirling within the cylindrical section from flowing into the fluid inflow section.

4. The centrifuge according to claim 3, wherein, The inflow prevention part protrudes inward from the end of the cylindrical part on the fluid inflow side of the cylindrical part at least on the cylindrical part side of the inlet.

5. A washing machine, wherein, This washing machine features: The centrifuge according to any one of claims 1 to 4; and A washing tub is used to wash laundry. The centrifuge is connected to the washing tank in such a way that fluid from the washing tank flows into the centrifuge.

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