Water level monitoring device for dishwashing machines

Abstract

A water level monitoring device (10) for a dishwashing machine is provided, which can suppress the poor vertical movement of the float (30) caused by foreign objects, thereby suppressing the reduction in the accuracy of water level monitoring. The water level monitoring device includes: a water tank (20); an inlet (21) that is provided through the lower part of the side wall (27) or the bottom wall (26) of the water tank; an outlet (22) that is provided through the side wall at a position above the inlet; a float guide (23) provided in the monitoring chamber (20A); a float that is provided in the monitoring chamber with the float guide inserted through the through hole (33) and moves vertically below the upper limit position; and a water level sensor (11) that monitors the vertical position of the float. The outlet is configured such that the lower end (22D) of the outlet is below the lower surface (30D1) of the float at the upper limit position and the upper end (22U) of the outlet is above the lower surface (30D2) of the float in the washing operation.

Description

Technical Field

[0001] This invention relates to a water level monitoring device for a dishwashing machine. Background Technology

[0002] Japanese Patent Application Publication No. 2014-14585 discloses an example of a water level monitoring device for a conventional dishwashing machine. This water level monitoring device is installed in a dishwashing machine that has a washing tank, a washing mechanism, and a drainage mechanism.

[0003] The cleaning tank holds the items to be cleaned. The cleaning tank stores cleaning water for cleaning the items. The cleaning mechanism includes a pump, fixed cleaning nozzles, and rotating cleaning nozzles. The cleaning mechanism performs a cleaning operation within the cleaning tank, using the cleaning water to clean the items.

[0004] The drainage system includes a drain pipe and a pump shared with the cleaning system. The drain pipe extends from the cleaning tank to the outside. During cleaning operation, the pump rotates in the opposite direction to pump cleaning water from the cleaning tank to the drain pipe. Thus, the drainage system discharges the cleaning water from the cleaning tank.

[0005] The water level monitoring device is positioned midway through the drain pipe to monitor the water level of the cleaning water in the cleaning tank. Specifically, the water level monitoring device includes an auxiliary water tank, a mounting plate, a float guide, a float, and a water level sensor.

[0006] A monitoring chamber is designated within the auxiliary water tank. The lowermost part of the auxiliary water tank is connected to the middle of the drain pipe via a flexible hose. A mounting plate is configured to cover the auxiliary water tank. A float guide protrudes upward from the mounting plate and has multiple guide holes arranged vertically within it.

[0007] The float is positioned in the monitoring chamber with its shaft protruding upwards from its upper surface and inserted into the guide holes of the float guide. The float's specific gravity is less than that of the cleaning water, and it moves vertically below its upper limit position as the amount of cleaning water in the monitoring chamber increases or decreases, guided by the guide holes of the float guide. The water level sensor is a reed switch held in the float guide, monitoring the float's vertical position.

[0008] However, for the water level monitoring devices of the aforementioned existing dishwashing machines, sometimes there are fine and light foreign objects mixed in with the washing water flowing into the monitoring chamber. Specifically, the foreign objects are food or tea residues that are mixed into the washing water in the washing tank during the washing operation and are not captured by the leftover food filter when draining.

[0009] Therefore, when the cleaning water in the cleaning tank is drained, if the monitoring chamber becomes full due to the cleaning water containing foreign objects, causing the float to rise to its upper limit, the foreign objects will float at the top of the monitoring chamber and easily adhere to the inner wall of the auxiliary water tank, the shaft of the float, and the guide holes of the float guide. As a result, the water level monitoring device is prone to poor vertical movement of the float due to foreign objects, which may further complicate the reduction in water level monitoring accuracy. Summary of the Invention

[0010] Therefore, a non-limiting objective of the present invention is to provide a water level monitoring device for a dishwashing machine that can suppress improper vertical movement of the float caused by foreign objects, thereby preventing a decrease in the accuracy of water level monitoring. This objective is solved by solution 1. Further extensions of the invention are described in other solutions.

[0011] The present invention relates to a water level monitoring device for a dishwashing machine, which includes: a washing tank for receiving and storing items to be washed; a washing mechanism for performing a washing operation within the washing tank using the washing water to wash the items; and a drainage mechanism having a drain pipe extending from the washing tank to the outside and a pump for pumping the washing water from the washing tank to the drain pipe, and for discharging the washing water from the washing tank.

[0012] The water level monitoring device of the dishwashing machine is positioned midway through the drain pipe to monitor the water level of the washing water in the washing tank. The water level monitoring device comprises:

[0013] A water tank having a bottom wall, an upper wall opposite the bottom wall from above, a cylindrical side wall connected to the bottom wall and the upper wall, and a monitoring chamber inside;

[0014] The inlet is disposed through the lower part of the side wall or the bottom wall and is connected to the pump side of the drain pipe;

[0015] The outlet is disposed through the side wall at a position above the inlet and connected to the opposite side of the pump of the drain pipe;

[0016] A float guide is configured to extend vertically within the monitoring chamber;

[0017] The float, having a through hole extending vertically, is positioned in the monitoring chamber with the float guide inserted through the through hole. Its specific gravity is less than that of the cleaning water. As the amount of cleaning water in the monitoring chamber increases or decreases, it is guided by the float guide, thereby moving vertically below its upper limit position.

[0018] A water level sensor is installed on the float guide and monitors the vertical position of the float.

[0019] The outlet is configured such that its lower end is below the lower surface of the float located at the upper limit position, and its upper end is above the lower surface of the float during the cleaning operation.

[0020] In the water level monitoring device (hereinafter simply referred to as "water level monitoring device") of the dishwashing machine of the present invention, the lower end of the outlet is configured to be below the lower surface of the float, which is located at the upper limit position. Therefore, when the washing water in the washing tank is discharged, even if the washing water containing foreign objects fills the monitoring chamber and causes the float to rise to the upper limit position, the float will not completely block the outlet. This allows foreign objects floating above the monitoring chamber to be quickly discharged to the outside of the monitoring chamber. Consequently, foreign objects are less likely to adhere to the inner wall of the water tank, the through-hole of the float, and the float guide.

[0021] In addition, during the cleaning operation, the cleaning water stored in the cleaning tank is used by the cleaning mechanism for cleaning, so the water level in the cleaning tank temporarily drops.

[0022] Here, depending on the structure of the cleaning and drainage mechanisms and their operating conditions, the position of the float sometimes drops from the upper limit position during cleaning operation, and sometimes it does not drop from the upper limit position.

[0023] As a first specific example, the following structure can be described: a single pump, which rotates forward for cleaning and reverses for drainage, is used in both the drainage and cleaning mechanisms, and the spray pressure from the pump during forward rotation also acts on the drain pipe. In this structure, depending on the magnitude of the spray pressure acting on the drain pipe, the height difference between the pump and the water level monitoring device, and other operating conditions, the float position may sometimes decrease from the upper limit position and sometimes may not decrease from the upper limit position during cleaning operation.

[0024] As a second specific example, the following structure can be cited: a single pump, which rotates forward for cleaning and reverses for drainage, is used in both the drainage and cleaning mechanisms. When the pump rotates forward, the valve body is pushed by the jet pressure to close the inlet of the drain pipe. In this structure, sometimes, during the rise of the jet pressure from 0, the valve body's operation becomes unstable, failing to reliably close the inlet of the drain pipe. As a result, the cleaning water in the drain pipe moves towards the pump side, causing the float position to drop from the upper limit position during cleaning operation. Alternatively, in this structure, sometimes the jet pressure rises from 0, causing the valve body to immediately close the inlet of the drain pipe, thus preventing the float position from dropping from the upper limit position during cleaning operation.

[0025] As a third specific example, the following structure can be described: the cleaning mechanism has a pump different from the pump of the drainage mechanism, and when the pump of the cleaning mechanism is activated and the pump of the drainage mechanism is stopped, the cleaning water in the drain pipe can move towards the pump side of the drainage mechanism. According to this structure, the position of the float descends from the upper limit position during cleaning operation.

[0026] At these times, since the upper end of the outlet is positioned above the lower surface of the float during the cleaning operation, foreign objects are unlikely to remain above the upper end of the outlet during the cleaning operation, thus making it difficult for them to adhere to the inner wall of the water tank, the through hole of the float, and the float guide.

[0027] Therefore, the water level monitoring device of the dishwashing machine of the present invention can suppress the poor vertical movement of the float caused by foreign objects, thereby suppressing the reduction in the accuracy of water level monitoring.

[0028] In another aspect of the invention, it is preferred that the position of the float decreases from the upper limit position during the cleaning operation. Furthermore, the outlet is preferably positioned such that the upper end of the outlet is below the midpoint between the upper and lower surfaces of the float at the upper limit position, and the lower end of the outlet is above the upper surface of the float during the cleaning operation.

[0029] In this configuration, since the upper end of the outlet is positioned below the midpoint between the upper and lower surfaces of the float at its upper limit, even if the monitoring chamber is filled with cleaning water containing foreign objects and the float rises to its upper limit when the cleaning water in the cleaning tank is discharged, the area of ​​the outlet blocked by the float can be reduced. This allows for more rapid discharge of foreign objects floating above the monitoring chamber to the outside of the monitoring chamber. Consequently, foreign objects are less likely to adhere to the inner wall of the water tank, the through-hole of the float, and the float guide. Furthermore, since the lower end of the outlet is positioned above the upper surface of the float during cleaning operation, the water level in the cleaning tank temporarily drops during cleaning operation, and the float position also drops. At this time, foreign objects are less likely to remain above the lower end of the outlet, thus making it difficult for them to adhere to the inner wall of the water tank, the through-hole of the float, and the float guide. As a result, this water level monitoring device can further limit the vertical movement of the float caused by foreign objects.

[0030] In another aspect of the invention, a pre-drainage outlet is preferably provided through the upper wall to discharge the cleaning water flowing into the monitoring room to the outside of the monitoring room.

[0031] In this situation, even if a large amount of cleaning water is discharged through the drain pipe, filling the monitoring chamber and the cleaning water containing foreign objects intrudes to a position above the float that has risen to its upper limit, the cleaning water containing foreign objects can be quickly discharged from the pre-drain outlet. Therefore, this water level monitoring device can further suppress the adhesion of foreign objects to the inner wall of the water tank, the float, and the float guide, and can further suppress the poor vertical movement of the float caused by foreign objects.

[0032] In another aspect of the invention, a portion of the pre-drainage path extending from the pre-drainage outlet to the outside of the monitoring room is preferably reduced in diameter.

[0033] In this situation, when the monitoring chamber is full, the cleaning water can be preferentially discharged from the outlet compared to the partially narrowed pre-drainage path. Furthermore, the remaining unnarrowed portion of the pre-drainage path allows the cleaning water flowing into it to quickly return to the monitoring chamber without stagnating in the pipe, preventing it from becoming full. As a result, the water level monitoring device can prevent foreign matter contained in the cleaning water from remaining in the pre-drainage path.

[0034] In another embodiment of the invention, the inlet is preferably disposed through the side wall, such that the first flow direction of the cleaning water flowing from the inlet into the monitoring chamber is a direction toward the circumferential side of the axis of the float guide. Furthermore, the outlet is preferably disposed through the side wall, such that the second flow direction of the cleaning water flowing from the monitoring chamber to the outlet is a direction toward the circumferential side.

[0035] In this situation, the cleaning water flowing in along the first flow direction easily swirls around the axis of the float guide. Furthermore, the cleaning water, while swirling, reaches the outlet, and this swirling flow is easily promoted by flowing out along the second flow direction. As a result, the water level monitoring device can suppress foreign matter from adhering to the inner wall of the tank, and can further suppress poor vertical movement of the float caused by foreign matter. In addition, the swirling flow allows heavier foreign matter to be discharged from the outlet, thus keeping a large area of ​​the monitoring chamber, including the bottom wall, clean. As a result, the water level monitoring device can further suppress poor vertical movement of the float caused by foreign matter.

[0036] In another aspect of the invention, the float is preferably formed in a ring shape centered on an axis. Furthermore, it is preferable that a plurality of fins protrude from at least one of the lower surface and the outer peripheral surface of the float.

[0037] In this situation, the swirling flow causes the float to rotate as it collides with multiple vanes, thereby preventing foreign objects from adhering to the float and its guide. As a result, the water level monitoring device can further suppress improper vertical movement of the float caused by foreign objects.

[0038] Other aspects and advantages of the invention will become apparent from the embodiments disclosed in the following description and drawings, the illustrations shown in the drawings, and the concept of the invention as disclosed in the specification and the drawings as a whole. Attached Figure Description

[0039] Figure 1 This is a cross-sectional schematic diagram of a dishwashing machine that uses the water level monitoring device of the embodiment.

[0040] Figure 2 This is a perspective view of the water level monitoring device in the embodiment.

[0041] Figure 3 The embodiment relates to a water level monitoring device, and is a perspective view of the main body of the water tank.

[0042] Figure 4 This is an exploded perspective view of the water level monitoring device in the embodiment, and is a view excluding the main body of the water tank.

[0043] Figure 5 This is a cross-sectional view of the water level monitoring device in the embodiment.

[0044] Explanation of reference numerals in the attached figures

[0045] 1…Dishwashing machine; 10…Water level monitoring device; TW1…Items to be washed (dishwashing); 7…Washing tank; 61, 62…Washing mechanism (61…nozzle, 62…pump); P2, 62…Drainage mechanism (P2…drain pipe, 62…pump); 26…Bottom wall; 29…Upper wall (top cover); 27…Side wall; 20A…Monitoring chamber; 20…Water tank; 21…Inlet; 22…Outlet; 23…Float guide; 33…Through hole; 30…Float; 11…Water level sensor; 22D…Lower end of outlet; 22U…Upper end of outlet; 30D…Float Lower surface; 30U… Upper surface of the float; 30D1… Lower surface of the float at the upper limit position; 30U1… Upper surface of the float at the upper limit position; 30D2… Lower surface of the float during cleaning operation; 30U2… Upper surface of the float during cleaning operation; 30C1… Midpoint between the upper and lower surfaces of the float at the upper limit position; 28… Pre-drainage port; P3… Pre-drainage path; X23… Axis of the float guide; R1… Direction towards one side of the circumferential axis of the float guide; DR1… First flow direction; DR2… Second flow direction; 35… Multiple blades. Detailed Implementation

[0046] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[0047] like Figure 1As shown, the water level monitoring device 10 in this embodiment is an example of a specific embodiment of the water level monitoring device for the dishwashing machine of the present invention. The water level monitoring device 10 is equipped with the dishwashing machine 1. The dishwashing machine 1 is a front-surface push-pull type dishwashing machine installed below the ceiling CT1 of the integrated kitchen.

[0048] In this embodiment, the side of the integrated kitchen opposite the user and the housing 9 will be utilized. Figure 1 The left side of the paper is defined as the front of the casing 9, and its opposite side is... Figure 1 The right side of the paper is defined as the rear of housing 9. Additionally, the left side, i.e., when the user is facing housing 9... Figure 1 The inside is defined as the left side of shell 9, and the right side, i.e. Figure 1 The paper side and the front side are defined as the right side of shell 9. Furthermore, Figure 2 The forward / backward, left / right, and up / down directions shown in subsequent diagrams are all consistent with... Figure 1 The corresponding representation is made.

[0049] Housing, cleaning tank and cover

[0050] The dishwashing machine 1 has a housing 9, a washing tank 7, and a cover 8.

[0051] The housing 9 is approximately box-shaped. The top of the housing 9 is covered by a top plate CT1. The housing 9 has a housing opening 9H. The housing opening 9H opens a large area from the upper end to the lower end of the front of the housing 9, and communicates the interior of the housing 9 with the exterior.

[0052] The cleaning tank 7 is housed inside the casing 9. Figure 1 The cleaning tank 7 shown is positioned for storage. A sliding track mechanism (not shown) is arranged between the side of the cleaning tank 7, which is approximately box-shaped, and the inner wall of the housing 9. Although not shown, the cleaning tank 7 can slide relative to the housing 9 using this sliding track mechanism.

[0053] The cleaning tank 7 has an opening 7H. The opening 7H makes the upper part of the cleaning tank 7 open. A handle 7G is provided at the upper front part of the cleaning tank 7.

[0054] The user holds the handle 7G and manually slides the cleaning tank 7 from its stored position towards the front of the housing 9. Although the illustration is omitted, this causes the cleaning tank 7 to be pulled forward from the housing opening 9H of the housing 9. Alternatively, the user can manually slide the pulled-out cleaning tank 7 towards the rear of the housing 9, thus returning the cleaning tank 7 to its stored position.

[0055] The cover 8 is disposed on the upper part inside the housing 9, allowing the opening 7H of the cleaning tank 7 to be closed and opened. The cover 8 is slidably linked to the cleaning tank 7 via a linkage mechanism (not shown). Figure 1 The positions shown, and although the illustrations are omitted, are from... Figure 1 The position shown rises while allowing the cleaning tank 7 to slide up and down between positions.

[0056] When the cleaning tank 7 is in the storage position, the opening 9H of the housing is closed, and the opening 7H is closed by the cover 8.

[0057] Although the illustration is omitted, the opening 7H exposed on the outside of the housing 9 is opened by the cover 8 remaining inside the housing 9 when the washing tank 7 is pulled out. Thus, the user can store the tableware TW1 in the washing tank 7 or remove the tableware TW1 from the washing tank 7 through the opening 7H.

[0058] Tableware category TW1 includes, for example, teacups, saucers, glasses, and other tableware, as well as chopsticks, spoons, forks, and other tableware utensils. Tableware category TW1 is an example of the "object to be cleaned" in this invention.

[0059] A water storage section 71 is provided at the bottom of the washing tank 7 to store the washing water for washing the tableware TW1. Additionally, a tableware basket 70 is provided inside the washing tank 7. The tableware TW1 is placed in the tableware basket 70.

[0060] An exhaust passage 79 is provided in the cleaning tank 7. One end of the exhaust passage 79 opens into the inner wall of the front surface of the cleaning tank 7. The other end of the exhaust passage 79 opens into the front surface of the cleaning tank 7 at a position lower than the handle 7G. Air inside the cleaning tank 7 is discharged to the outside of the cleaning machine, i.e., to the front of the housing 9, through the exhaust passage 79.

[0061] Water supply pipes, water supply solenoid valves, drain pipes, nozzles and pumps

[0062] The dishwashing machine 1 also includes a water supply pipe P1, a water supply solenoid valve 69, a drain pipe P2, a nozzle 61, and a pump 62.

[0063] Nozzle 61 and pump 62 are examples of the "cleaning mechanism" of the present invention. Drain pipe P2 and pump 62 are examples of the "drainage mechanism" of the present invention. That is, pump 62 serves as both a cleaning mechanism and a drainage mechanism.

[0064] Water supply pipe P1, water supply solenoid valve 69, and drain pipe P2 are housed within housing 9. Water supply pipe P1 supplies water to the washing tank 7 from a water source (not shown) located outside the dishwashing machine 1. Water supply solenoid valve 69 switches the water supply to the washing tank 7 by opening and closing water supply pipe P1.

[0065] Drain pipe P2 extends from the lower part of the water storage section 71 of the washing tank 7 and extends through the rear wall of the housing 9 to the outside of the dishwashing machine 1. Drain pipe P2 discharges the washing water stored in the water storage section 71 of the washing tank 7 to the outside of the dishwashing machine 1.

[0066] Nozzle 61 is disposed inside the cleaning tank 7. Pump 62 is assembled at the lower part of the water storage section 71 of the cleaning tank 7. Nozzle 61 and pump 62 perform a cleaning operation in the cleaning tank 7 to clean the tableware TW1 using cleaning water.

[0067] More specifically, nozzle 61 can spray cleaning water into the cleaning tank 7 from multiple spray holes. In order to reliably clean the multiple types of tableware TW1 stacked in the cleaning tank 7, and to clean the inner wall surface of the cleaning tank 7 and the tableware basket 70, the spray direction of nozzle 61 is varied in multiple directions.

[0068] Pump 62 rotates forward to supply cleaning water stored in the water reservoir 71 of the cleaning tank 7 to nozzle 61 and spray it into the cleaning tank 7. Since the sprayed cleaning water is stored in the water reservoir 71, it is repeatedly supplied to nozzle 61 by pump 62.

[0069] On the other hand, the pump 62 reverses its operation to pressurize the cleaning water stored in the water storage section 71 of the cleaning tank 7 to the drain pipe P2, and discharges the cleaning water to the outside of the dishwashing machine 1 through the drain pipe P2.

[0070] At this point, almost all the foreign matter in the washing water is captured by the leftover food filter 67 installed in the water storage section 71. However, fine and lightweight foreign matter such as food residue and tea leaves will not be captured by the leftover food filter 67 but will be pumped to the drain pipe P2.

[0071] Heater, temperature sensor and drying fan

[0072] The dishwashing machine 1 also has a heater 63, a temperature sensor 63S, and a drying fan 68.

[0073] The heater 63 is located at the bottom of the water storage section 71. The drying fan 68 is mounted on the rear wall of the washing tank 7. The temperature sensor 63S is located below the heater 63 relative to the bottom of the water storage section 71.

[0074] Heater 63 heats the cleaning water stored in the water storage section 71 of the cleaning tank 7, or the air in the cleaning tank 7.

[0075] Temperature sensor 63S monitors the temperature of the cleaning water stored in the water storage section 71 of the cleaning tank 7 or the air in the cleaning tank 7 near heater 63.

[0076] The drying fan 68 rotates while the heater 63 is in operation, thereby sending heated air into the washing tank 7 to dry the tableware TW1. The air sent into the washing tank 7 by the drying fan 68 is discharged to the outside of the tableware washing machine 1 through the exhaust passage 79.

[0077] Water level monitoring device

[0078] The water level monitoring device 10 is a float-type sensor that monitors the water level of the cleaning water in the cleaning tank 7. The water level monitoring device 10 is assembled on the lower part of the rear wall of the cleaning tank 7 and is positioned in the middle of the drain pipe P2.

[0079] The pump 62 side is designated as the first drain pipe P21 relative to the water level monitoring device 10 of drain pipe P2. The opposite side of the pump 62 is designated as the second drain pipe P22 relative to the water level monitoring device 10 of drain pipe P2.

[0080] In addition, Figure 1 In the diagram, for ease of reading, the position of the water level monitoring device 10 is shown to be further away from the rear wall of the cleaning tank 7 than in reality, and the pre-drainage path P3 is also shown to be longer in the front-to-back direction than in reality.

[0081] like Figures 2-5 As shown, the water level monitoring device 10 has a water tank 20, an inlet 21, an outlet 22, a float guide 23, a float 30, and a water level sensor 11.

[0082] Water tank 20 has: Figure 2 , Figure 3 and Figure 5 The main body of the water tank 25 shown; and Figure 2 , Figure 4 and Figure 5 The top cover 29 and the cover 29C are shown. The top cover 29 is an example of the "upper wall" of the present invention.

[0083] In this embodiment, the water tank body 25, the top cover 29, and the cover 29C are resin molded products manufactured by injection molding of thermoplastic resin, etc.

[0084] like Figure 3 As shown, the main body 25 of the water tank integrally comprises a bottom wall 26 and side walls 27. When viewed from above, the bottom wall 26 is an approximately square flat plate with rounded corners at all four corners. The side walls 27 are formed into a quadrangular cylindrical shape by comprising a front wall 27A, a rear wall 27B, a left wall 27L, and a right wall 27R. The side walls 27 extend in the vertical direction, and their lower ends connect to the bottom wall 26.

[0085] A base 24 is formed at the center of the upper surface of the bottom wall 26. The base 24 protrudes upward in a cylindrical shape with respect to an axis X23 extending in the vertical direction. The interior of the base 24 is sealed by a partition wall 24W.

[0086] A lower limit stop 26S is formed around the base 24 on the upper surface of the bottom wall 26. The lower limit stop 26S consists of multiple ribs that protrude radially outward from the outer periphery of the base 24 toward the axis X23.

[0087] like Figure 3 and Figure 5 As shown, a circular inlet 21 is provided through the lower and rear part of the right wall 27R of the water tank. Figure 5 In the middle, the right wall 27R of the water tank is located at the front of the paper; therefore, the inlet 21 is shown by a double-dotted line. (See image below.) Figure 3 As shown, the inlet 21 protrudes to the right in a cylindrical shape from the right wall 27R of the water tank. Figure 1 and Figure 2 As shown, the inlet 21 is connected to the first drain pipe P21 on the pump 62 side of the drain pipe P2.

[0088] like Figure 5 As shown, a circular outlet 22 is provided above and behind the flow inlet 21 on the left wall 27L of the water tank. Figure 3 As shown, the outlet 22 protrudes to the left in a cylindrical shape from the left wall 27L of the water tank. Figure 1 and Figure 2 As shown, outlet 22 is connected to the second drain pipe P22 on the opposite side of pump 62 of drain pipe P2.

[0089] like Figure 3 As shown, the direction of the cleaning water pressurized in the first drain pipe P21 flowing into the monitoring chamber 20A from the inlet 21 is designated as the first flow direction DR1. The direction of the cleaning water flowing out of the monitoring chamber 20A from the outlet 22 is designated as the second flow direction DR2.

[0090] The inlet 21 is provided through the right wall 27R of the water tank in such a way that the first flow direction DR1 is directed toward one side of the circumferential direction of the axis X23 of the float guide 23.

[0091] The outlet 22 is disposed through the left wall 27L of the water tank in such a way that the second flow direction DR2 is oriented toward one side of the circumference R1. In this embodiment, the first flow direction DR1 and the second flow direction DR2 are the same, both facing to the left.

[0092] Based on the structure of the inlet 21 and outlet 22, the cleaning water flowing into the monitoring chamber 20A along the first flow direction DR1 can easily swirl around the axis X23 of the float guide 23. In addition, the cleaning water that reaches the outlet 22 while swirling out along the second flow direction DR2 can easily promote the swirling flow.

[0093] like Figure 4 As shown, when viewed from above, the top cover 29 is an approximately square plate with rounded corners at all four sides. On the lower surface of the top cover 29, a rectangular annular fitting rib 29R is formed to protrude downwards.

[0094] A float guide 23 is formed in the center of the lower surface of the upper cover 29. The float guide 23 protrudes downward in a cylindrical shape, centered on the axis X23. Figure 5 As shown, the interior of the float guide 23 is sealed by the partition wall 23W. The internal space of the float guide 23 above the partition wall 23W is designated as the sensor storage section 23S.

[0095] like Figure 4 and Figure 5 As shown, an upper limit stop 29S is formed around the float guide 23 on the lower surface of the upper cover 29. The upper limit stop 29S consists of multiple ribs that protrude radially outward from the root of the outer peripheral surface of the float guide 23 toward the axis X23.

[0096] A rectangular pre-drainage port 28 extending elongated in the left-right direction is provided through the front part of the top cover 29. The portion of the pre-drainage port 28 extending in the left-right direction in front of the fitting rib 29R protrudes upward from the rear adjacent position.

[0097] A connecting portion 28C is integrally formed on the upper part of the pre-drainage port 28. The connecting portion 28C communicates with the pre-drainage port 28 and protrudes forward in a cylindrical shape.

[0098] The cover 29C is secured to the top cover 29 by screws 29B while the sensor storage section 23S is closed from above.

[0099] The top cover 29 is connected to the side wall 27 by means of a sealing component such as a sealant or an elastic sealing ring (not shown) when the fitting rib 29R is fitted into the upper edge of the side wall 27 and is opposite to the bottom wall 26 from above.

[0100] like Figure 5 As shown, a monitoring chamber 20A is defined inside the water tank 20. The monitoring chamber 20A is a space surrounded by a bottom wall 26, side walls 27, and a top cover 29. The float guide 23 extends vertically within the monitoring chamber 20A, and its lower end is embedded in the base 24 and held in place.

[0101] The water tank 20 has a fixing protrusion 20D that protrudes forward from the front wall 27A of the water tank, and a fixing piece 20E that protrudes upward from the top cover 29. The rear wall of the cleaning tank 7 has a connecting recess 7F; a fixing recess 7D located below the connecting recess 7F; and a fastening part 7E located above the connecting recess 7F.

[0102] The connecting part 28C is embedded in the connecting recess 7F, the fixing protrusion 20D is embedded in the fixing recess 7D, and the fixing piece 20E is fastened to the fastening part 7E by the screw 20B, thereby assembling the water tank 20 onto the rear wall of the cleaning tank 7.

[0103] A connecting hole 7C is provided through the rear wall of the cleaning tank 7 in the front-to-back direction. The connecting hole 7C communicates with the lower end of the connecting portion 28C, which is embedded in the connecting recess 7F, and the interior of the cleaning tank 7. The connecting portion 28C and the connecting hole 7C constitute a pre-drainage path P3 extending from the pre-drainage port 28 to the outside of the monitoring chamber 20A. The connecting hole 7C, as part of the pre-drainage path P3, is narrower than the connecting portion 28C.

[0104] The pre-drain outlet 28 can discharge the cleaning water flowing into the monitoring chamber 20A to the outside of the monitoring chamber 20A, and more specifically to the cleaning tank 7, via the pre-drain path P3. In addition, the pre-drain outlet 28 also serves as a vent to discharge the air inside the monitoring chamber 20A to the outside of the monitoring chamber 20A.

[0105] The float 30 is formed as an annular shape with a through hole 33 extending vertically around the axis X23. The outer peripheral surface of the float 30 is a cylindrical surface centered on the axis X23.

[0106] like Figure 4 As shown, a plurality of blades 35 are provided protruding downward on the lower surface 30D of the float 30. Each blade 35 extends radially in a rib-like manner along the axis X23.

[0107] like Figure 5 As shown, multiple blades 35 are also provided protruding upwards on the upper surface 30U of the float 30. The blades 35 on the upper surface 30U are the same as those on the lower surface 30D, except that they protrude in the opposite direction.

[0108] The float 30 can be, for example, a foamed body composed of independent air bubbles made of resin, rubber, or soft materials; a hollow resin molded product formed by blow molding; or a hollow resin molded product consisting of two connected parts, such as a Japanese-style "hollow cake shell," thereby making its specific gravity less than that of the washing water. Although the illustration is omitted, a permanent magnet is built into the inside of the float 30.

[0109] The float 30 is positioned within the monitoring chamber 20A such that the float guide 23 is inserted through the through hole 33. The float 30 is guided by the float guide 23 as the amount of cleaning water in the monitoring chamber 20A increases or decreases, moving vertically between the upper limit position and the lower limit position.

[0110] like Figure 5 As shown by the double-dotted line, the upper limit position of the float 30 is the position where the upper surface 30U of the float 30 abuts against the upper limit stop 29S. Although the illustration is omitted, the lower limit position of the float 30 is the position where the lower surface 30D of the float 30 abuts against the lower limit stop 26S.

[0111] The water level sensor 11 is a well-known reed switch disposed on the substrate and housed in the sensor housing 23S of the float guide 23. The signal line of the water level sensor 11 is led out from the wiring outlet formed in the cover 29C and connected to the control unit C1 described later.

[0112] The water level sensor 11 causes its internal contacts to disconnect as the permanent magnet embedded in the float 30 approaches and separates, thereby monitoring the vertical position of the float 30. In this embodiment, the water level sensor 11 is configured to detect whether the float 30 is in a certain position. Figure 5 The upper limit position indicated by the double-dotted line is the location to be monitored.

[0113] When the amount of cleaning water stored in the water storage section 71 of the cleaning tank 7 reaches the amount required to perform the cleaning operation, the float 30 reaches the upper limit position. In addition, when the cleaning water stored in the water storage section 71 of the cleaning tank 7 is discharged using the drain pipe P2, the float 30 reaches the upper limit position when the amount of cleaning water pressurized into the monitoring chamber 20A is large.

[0114] During cleaning operation, the water level in the cleaning tank 7 temporarily decreases according to the amount of cleaning water sprayed from the nozzle 61, and the cleaning water level in the monitoring chamber 20A also temporarily decreases. In this embodiment, a single pump 62, which rotates forward for cleaning and reverses for drainage, is used in both the drainage and cleaning mechanisms. Furthermore, the spray pressure from the pump 62 during forward rotation also acts on the first drain pipe P21. Additionally, depending on the spray pressure acting on the first drain pipe P21 and the height difference between the pump 62 and the water level monitoring device 10, the float 30's position decreases from its upper limit position during cleaning operation. Therefore, during cleaning operation, the float 30 temporarily decreases from its upper limit position. Figure 5 The upper limit position indicated by the double-dotted line drops to Figure 5 The position is indicated by the solid line.

[0115] Outlet configuration

[0116] The outlet 22 is configured such that the lower end 22D of the outlet 22 is below the lower surface 30D1 of the float 30 which is in the upper limit position, and the upper end 22U of the outlet 22 is above the lower surface 30D2 of the float 30 during cleaning operation, i.e., during the process of spraying cleaning water from the nozzle 61.

[0117] More preferably, the outlet 22 is configured such that the upper end 22U of the outlet 22 is below the midpoint 30C1 between the upper surface 30U1 and the lower surface 30D1 of the float 30 located at the upper limit position, and the lower end 22D of the outlet 22 is above the upper surface 30U2 of the float 30 in cleaning operation.

[0118] Control unit and input / output unit

[0119] like Figure 1 As shown, the dishwashing machine 1 also includes a control unit C1 and an input / output unit 40. The control unit C1 is located on the front surface side of the washing tank 7, below the handle 7G. The input / output unit 40 is located at the upper end of the front surface side of the washing tank 7.

[0120] The control unit C1 is an electronic circuit unit, which includes: a CPU (not shown), a memory consisting of storage elements such as ROM and RAM; an interface circuit for transmitting and receiving signals with the controlled object; and a power supply circuit for controlling the power supply to the controlled object. The memory stores programs and setting information for causing the dishwashing machine 1 to perform operations.

[0121] The control unit C1 controls the operation of the pump 62, heater 63, and drying fan 68, and receives monitoring signals from the temperature sensor 63S and the water level sensor 11 of the water level monitoring device 10. Additionally, the control unit C1 receives monitoring signals from sensors not shown in the diagram, such as a position sensor that monitors whether the washing tank 7 is in the storage position, and a lock sensor that monitors whether the washing tank 7 is locked in the storage position.

[0122] The input / output unit 40 has multiple buttons (not shown) for user input operations. Additionally, the input / output unit 40 includes lights and display elements capable of displaying numbers, text, etc., to transmit various information to the user. The input / output unit 40 transmits user input operations to the control unit C1 and displays the information transmitted from the control unit C1.

[0123] With the washing tank 7 in its retracted position, the entire input / output section 40 is concealed by the ceiling panel CT1 of the integrated kitchen. Therefore, the user cannot operate or visually inspect the input / output section 40.

[0124] On the other hand, although the illustration is omitted, by pulling the washing tank 7 out of its storage position, the entire input / output unit 40 is moved to a position forward of the ceiling panel CT1 of the overall kitchen. Therefore, the user can operate and visually inspect the input / output unit 40.

[0125] Cleaning operation

[0126] In the dishwashing machine 1 with the above-described structure, the washing operation is performed in the following order: with the washing tank 7 pulled out from the storage position, the user operates the input / output unit 40 to instruct the start of the washing operation, and then pushes the washing tank 7 back into the storage position.

[0127] Therefore, the control unit C1 activates the pump 62 based on the condition that the cleaning tank 7 is in the stored position using a position sensor (not shown) and the cleaning tank 7 is locked in the stored position using a locking sensor (not shown), thereby performing a cleaning operation that sprays cleaning water from the nozzle 61 into the cleaning tank 7. That is, after confirming that the opening 7H of the cleaning tank 7 is closed by the cover 8, the control unit C1 activates the pump 62 to perform the cleaning operation.

[0128] During the cleaning operation, the control unit C1 sequentially executes the cleaning steps using cleaning water containing detergent and the rinsing steps using clean cleaning water, thereby cleaning the tableware TW1 in the cleaning tank 7.

[0129] At the beginning and during these steps, the control unit C1 appropriately opens the water supply solenoid valve 69 to supply water to the cleaning tank 7 via the water supply pipe P1. At this time, the control unit C1 determines whether the amount of cleaning water stored in the water storage section 71 of the cleaning tank 7 has reached the amount required to perform the cleaning operation based on the monitoring signal from the water level sensor 11, and closes the water supply solenoid valve 69 when it has reached the required amount.

[0130] In addition, during and at the end of these steps, the control unit C1 appropriately reverses the pump 62 to pump cleaning water from the water storage section 71 of the washing tank 7 to the drain pipe P2, and discharges it to the outside of the dishwashing machine 1 through the drain pipe P2. At this time, the control unit C1 judges the discharge status and discharge completion status of the cleaning water discharged through the drain pipe P2 based on the monitoring signal from the water level sensor 11, and controls the reverse operation of the pump 62.

[0131] Furthermore, the control unit C1 performs a drying step at the end of the cleaning operation, causing the heater 63 and the drying fan 68 to operate appropriately to dry the tableware TW1 in the cleaning tank 7, and then ends the cleaning operation.

[0132] Effects

[0133] In the water level monitoring device 10 of the embodiment, such as Figure 5 As shown, the lower end 22D of the outlet 22 is positioned below the lower surface 30D1 of the float 30, which is at its upper limit position. Therefore, when the cleaning water in the cleaning tank 7 is discharged, even if the monitoring chamber 20A is filled with cleaning water containing foreign objects, causing the float 30 to rise to its upper limit position, the float 30 will not completely block the outlet 22. This allows foreign objects floating above the monitoring chamber 20A to be quickly discharged outside the monitoring chamber 20A. Consequently, foreign objects are less likely to adhere to the inner wall of the water tank 20, the through hole 33 of the float 30, and the float guide 23.

[0134] Furthermore, during the cleaning operation, the cleaning water stored in the cleaning tank 7 is used for cleaning using the nozzle 61 and pump 62. Therefore, the water level in the cleaning tank 7 temporarily drops, and the position of the float 30 also drops. At this time, since the upper end 22U of the outlet 22 is positioned above the lower surface 30D2 of the float 30 during the cleaning operation, foreign objects are unlikely to remain above the upper end 22U of the outlet 22 during the cleaning operation, and thus are unlikely to adhere to the inner wall of the water tank 20, the through hole 33 of the float 30, and the float guide 23.

[0135] Therefore, the water level monitoring device 10 of the embodiment can suppress the poor vertical movement of the float 30 caused by foreign objects, thereby suppressing the reduction in the accuracy of water level monitoring.

[0136] Furthermore, in this water level monitoring device 10, the upper end 22U of the outlet 22 is positioned below the midpoint 30C1 between the upper surface 30U1 and the lower surface 30D1 of the float 30, which is at its upper limit position. Therefore, when the cleaning water in the cleaning tank 7 is discharged, even if the monitoring chamber 20A is filled with cleaning water containing foreign objects, causing the float 30 to rise to its upper limit position, the area of ​​the outlet 22 blocked by the float 30 can be reduced. This allows for the rapid discharge of foreign objects floating above the monitoring chamber 20A. Consequently, foreign objects are less likely to adhere further to the inner wall of the water tank 20, the through hole 33 of the float 30, and the float guide 23. Furthermore, since the lower end 22D of the outlet 22 is positioned above the upper surface 30U2 of the float 30 during cleaning operation, the water level in the cleaning tank 7 temporarily drops during cleaning. Consequently, when the float 30 also drops, foreign objects are less likely to remain above the lower end 22D of the outlet 22, thus making it difficult for them to adhere to the inner wall of the tank 20, the through hole 33 of the float 30, and the float guide 23. As a result, the water level monitoring device 10 can further suppress poor vertical movement of the float 30 caused by foreign objects.

[0137] Furthermore, the water level monitoring device 10 has a pre-drainage outlet 28 through the top cover 29, which discharges the cleaning water flowing into the monitoring chamber 20A to the outside of the monitoring chamber 20A. According to this structure, even if a large amount of cleaning water is discharged through the drain pipe P2, causing the monitoring chamber 20A to become full, and cleaning water containing foreign matter intrudes to a position above the float 30 which has risen to its upper limit, the cleaning water containing foreign matter can be quickly discharged from the pre-drainage outlet 28. Therefore, the water level monitoring device 10 can further suppress the adhesion of foreign matter to the inner wall of the water tank 20, the float 30, and the float guide 23, and can further suppress poor vertical movement of the float 30 caused by foreign matter.

[0138] Furthermore, in this water level monitoring device 10, a portion of the pre-drainage path P3 extending from the pre-drainage outlet 28 to the outside of the monitoring chamber 20A, namely the connecting hole 7C, is narrower than the other portions of the pre-drainage path P3, namely the connecting portion 28C. According to this structure, when the monitoring chamber 20A is full, the connecting hole 7C, compared to the narrowed pre-drainage path P3, can preferentially discharge cleaning water from the outlet 22. Additionally, the non-narrowed connecting portion 28C of the pre-drainage path P3, when preventing a full state, allows the cleaning water flowing into the pre-drainage path P3 to quickly return to the monitoring chamber 20A without stagnating in the pipe. As a result, the water level monitoring device 10 can suppress the residue of foreign matter contained in the cleaning water within the pre-drainage path P3.

[0139] In addition, in this water level monitoring device 10, such as Figure 3 As shown, an inlet 21 is provided at the lower and rear part of the right wall 27R of the water tank, such that the first flow direction DR1 is directed in a direction R1 toward the circumferential direction of the axis X23 of the float guide 23. Furthermore, an outlet 22 is provided at the upper and rear part of the left wall 27L of the water tank, such that the second flow direction DR2 is directed in a direction R1 toward the circumferential direction. With this structure, the cleaning water flowing in along the first flow direction DR1 easily swirls around the axis X23 of the float guide 23, and the cleaning water reaching the outlet 22 while swirling flows out along the second flow direction DR2, thereby easily promoting this swirling flow. As a result, the water level monitoring device 10 can suppress the adhesion of foreign objects to the inner wall surface of the water tank 20, and can further suppress poor vertical movement of the float 30 caused by foreign objects. Furthermore, the swirling flow allows heavier foreign objects to be discharged from the outlet 22, thus keeping a large area within the monitoring chamber 20A, including the bottom wall side, clean. As a result, the water level monitoring device 10 can further suppress improper vertical movement of the float 30 caused by foreign objects.

[0140] In addition, in this water level monitoring device 10, such as Figure 4As shown, the float 30 is formed in an annular shape centered on the axis X23. Furthermore, multiple vanes 35 protrude from the lower surface 30D and upper surface 30U of the float 30. According to this structure, the swirling flow collides with the multiple vanes 35 while flowing, causing the float 30 to rotate, thereby suppressing the adhesion of foreign objects to the float 30 and the float guide 23. As a result, the water level monitoring device 10 can further suppress poor vertical movement of the float 30 caused by foreign objects.

[0141] The present invention has been described above with reference to the embodiments. However, the present invention is not limited to the above embodiments. It goes without saying that appropriate changes can be made and applied within the scope of its spirit.

[0142] The positional relationship between the inlet 21 and outlet 22 in this embodiment is just one example, and the present invention is not limited to this structure. For example, it can be modified so that the outlet 22 is disposed through the left part of the front wall 27A of the water tank, so that the second flow direction DR2 faces forward and becomes the direction R1 facing the circumferential direction. In this case, the second flow direction DR2 is orthogonal to the first flow direction DR1. Alternatively, it can be modified so that the outlet 22 is disposed through the front part of the right wall 27R of the water tank, so that the second flow direction DR2 faces right and becomes the direction R1 facing the circumferential direction. In this case, the second flow direction DR2 is opposite to the first flow direction DR1. Moreover, it can be modified so that the outlet 22 is disposed through the right part of the rear wall 27B of the water tank, so that the second flow direction DR2 faces backward and becomes the direction R1 facing the circumferential direction. In this case, the second flow direction DR2 is orthogonal to the first flow direction DR1.

[0143] In one embodiment, the sidewall 27 is a quadrangular cylindrical shape; however, the structure of the present invention is not limited to this, for example, the sidewall may also be cylindrical.

[0144] In one embodiment, the inlet 21 is disposed through the lower part of the side wall 27; however, the structure of the present invention is not limited thereto. For example, the inlet may also be disposed through the bottom wall.

[0145] In this embodiment, the inlet 21 is a circular hole; however, the structure of the present invention is not limited to this. For example, the inlet can also be a rectangular hole or a polygonal hole. The outlet is the same.

[0146] In one embodiment, the float guide 23 extends downward from the upper cover 29 and is held by a base 24 protruding from the bottom wall 26; however, the structure of the invention is not limited thereto. For example, a structure in which the base 24 is removed from the bottom wall 26 and the lower end of the float guide 23 is not held is also included in the invention.

[0147] In this embodiment, the float 30 is annular; however, the structure of the present invention is not limited to this. For example, the float can be any shape as long as it has a through hole, and can also be a rectangular ring or a polygonal ring.

[0148] In one embodiment, a plurality of fins 35 are provided protruding from the lower surface 30D and the upper surface 30U of the float 30. However, the structure of the present invention is not limited to this. For example, the plurality of fins may be provided only on the lower surface of the float, or they may be provided on the outer peripheral surface of the float.

[0149] In this embodiment, a single pump 62, which rotates forward for cleaning and reverses for drainage, is used in both the drainage and cleaning mechanisms. The ejection pressure from the pump 62 during forward rotation also acts on the first drain pipe P21. Furthermore, depending on the magnitude of the ejection pressure acting on the first drain pipe P21 and the height difference between the pump 62 and the water level monitoring device 10, the float 30 descends from its upper limit position during cleaning operation. This invention is not limited to the structure of this embodiment. Three specific examples are listed below.

[0150] For example, similar to the embodiments, the present invention also applies the spray pressure of the pump when it performs forward rotation to the structure of the drain pipe. However, the position of the float may not drop from the upper limit position during the cleaning operation, depending on the magnitude of the spray pressure acting on the drain pipe, the height difference between the pump and the water level monitoring device, and other usage conditions.

[0151] Alternatively, the present invention can also be configured to use a single pump, which rotates forward for cleaning and reverses for drainage, in both the drainage and cleaning mechanisms. The valve body is pushed by the jet pressure during the pump's forward rotation to close the inlet of the drain pipe. In this configuration, if the valve body's operation is unstable and fails to reliably close the drain pipe inlet while the jet pressure is rising from 0, the cleaning water in the drain pipe moves towards the pump side, causing the float to drop from its upper limit position during cleaning operation. Alternatively, in this configuration, if the jet pressure rises from 0 and the valve body immediately closes the drain pipe inlet, the float's position does not drop from its upper limit position during cleaning operation.

[0152] Alternatively, the present invention can also be configured such that the cleaning mechanism has a pump different from the pump of the drainage mechanism, the cleaning water in the drain pipe can move toward the pump side of the drainage mechanism when the pump of the cleaning mechanism is activated and the pump of the drainage mechanism is stopped, and the position of the float does not drop from the upper limit position during the cleaning operation.

[0153] This invention can be used, for example, in a dishwashing machine or a dishwashing and drying machine.

Claims

1. A water level monitoring device (10) of a tableware washing machine (1), The tableware washing machine (1) has: a washing tub (7) that accommodates a washed object (TW1) and can store washing water for washing the washed object (TW1); a washing mechanism (61, 62) that performs a washing operation of washing the washed object (TW1) with the washing water in the washing tub (7); and a drain mechanism (P2, 62) that has a drain pipe (P2) extending from the washing tub (7) to the outside and a pump (62) that pressurizes and sends the washing water from the washing tub (7) to the drain pipe (P2) and drains the washing water in the washing tub (7); the water level monitoring device (10) of the tableware washing machine (1) is provided midway through the drain pipe (P2) and monitors the water level of the washing water in the washing tub (7), characterized in that the water level monitoring device (10) of the tableware washing machine (1) has: a water tank (20) that has a bottom wall (26), an upper wall (29) opposed to the bottom wall (26) from above, a side wall (27) formed in a cylindrical shape and connected to the bottom wall (26) and the upper wall (29), and divides a monitoring chamber (20A) inside; an inflow port (21) that is provided through the lower portion of the side wall (27) or the bottom wall (26) and connected to the pump (62) side of the drain pipe (P2); an outflow port (22) that is provided through a position of the side wall (27) above the inflow port (21) and connected to the opposite side of the pump (62) of the drain pipe (P2); a float guide (23) that is provided to extend in the vertical direction in the monitoring chamber (20A); a float (30) that has a through-hole (33) that penetrates in the vertical direction and is provided in the monitoring chamber (20A) in a state in which the float guide (23) is inserted into the through-hole (33), has a specific gravity smaller than that of the washing water, and is guided by the float guide (23) as the amount of the washing water in the monitoring chamber (20A) increases or decreases, thereby moving in the vertical direction below an upper limit position; and a water level sensor (11) that is provided to the float guide (23) and monitors the position of the float (30) in the vertical direction; and the outflow port (22) is disposed so that the lower end of the outflow port (22) is below the lower surface (30D1) of the float (30) at the upper limit position and so that the upper end of the outflow port (22) is above the lower surface (30D2) of the float (30) in the washing operation.

2. The water level monitoring device (10) of the tableware washing machine (1) according to claim 1, characterized in that it is configured so that the position of the float (30) decreases from the upper limit position in the washing operation. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ The flow outlet (22) is disposed so that the upper end of the flow outlet (22) is positioned below the midpoint (30C1) of the upper surface (30U1) and the lower surface (30D1) of the float (30) in the upper limit position, and so that the lower end of the flow outlet (22) is positioned above the upper surface (30U2) of the float (30) in the cleaning operation.

3. The water level monitoring device (10) of the dishwasher (1) according to claim 1 or 2, characterized in that A pre-drain port (28) through which the cleaning water flowing into the monitoring chamber (20A) is discharged outside the monitoring chamber (20A) is provided through the upper wall (29).

4. The water level monitoring device (10) of the dishwasher (1) according to claim 3, characterized in that A portion of a pre-drain path (P3) extending from the pre-drain port (28) to the outside of the monitoring chamber (20A) is reduced in diameter.

5. The water level monitoring device (10) of the dishwasher (1) according to any one of claims 1 to 4, characterized in that The flow inlet (21) is provided through the side wall (27) so that a first flow direction (DR1) in which the cleaning water flows from the flow inlet (21) into the monitoring chamber (20A) is a direction (R1) toward one side of a circumferential direction of an axis (X23) of the float guide (23), The flow outlet (22) is provided through the side wall (27) so that a second flow direction (DR2) in which the cleaning water flows from the monitoring chamber (20A) to the flow outlet (22) is a direction (R1) toward the one side of the circumferential direction.

6. The water level monitoring device (10) of the dishwasher (1) according to claim 5, characterized in that The float (30) is formed in a ring shape with the axis (X23) as a center, A plurality of fins (35) are provided protruding at least one of the lower surface (30D) and the outer peripheral surface of the float (30).

Images