Washing machine

Abstract

To reduce maintenance work required for a heating device.SOLUTION: The invention includes a case, a water drum that is placed inside the case, a washing drum that is placed inside the water drum, driving means that drives the rotation of the washing drum via a substantially vertical rotation shaft, a water discharge outlet through which a liquid used for washing in the water drum is discharged, and heating means via which the washing liquid is heated, and a recess that is formed in a manner in which it is set deeper than the inner bottom of the water drum and an attachment unit to which the heating means is attached are formed in the bottom of the water drum, and on the top of the heating means, a cover plate that covers the heating means is placed and the cover plate has a through-hole in a position that is off the top of the heating means and in the side close to the rotation shaft.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a washing machine for washing clothes and the like.

Background Art

[0002] Conventionally, as this type of washing machine, a washing machine has been proposed that makes it easier to remove dirt by raising the temperature of the washing liquid (see, for example, Patent Document 1).

[0003] FIG. 13 is a cross-sectional view of a conventional washing machine. In FIG. 13, it includes a water supply port 62 for supplying water to a water tank 63, and a switching valve 66 that branches the water supply path from the water supply port 62 to the water tank 63 into a main water path 64 and a bypass path 65, and a heater 67 is provided in the middle of the bypass path 65.

[0004] However, with this configuration, there is a problem that the flow path for supplying the heated washing liquid to the water tank 63 becomes complicated.

[0005] Therefore, in order to solve this problem, as shown in FIG. 14, it is conceivable to dispose a heater 72 at the bottom of the water tank 71.

[0006] FIG. 14 is a perspective view of a conventional water tank. In the water tank 71, a concave portion 73 is formed at the bottom, and the heater 72 is disposed so as to be located within the concave portion 73. A fixing portion 74 for fixing the heater 72 is formed on the outer peripheral side of the bottom of the water tank 71.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] However, in the conventional configuration, since the drain outlet is disposed near the heater, the drain water from the drain outlet flows near the heater, and there is a risk that the lint contained in the drain water gets caught on the heater. When lint gets caught on the heater, it is necessary to remove the lint from the heater, resulting in poor usability.

[0009] The present invention solves the above-described conventional problems, and an object thereof is to provide a washing machine capable of reducing the maintenance of a heating device.

Means for Solving the Problems

[0010] In order to solve the above-described conventional problems, a washing machine according to the present invention includes a housing, a water tank disposed in the housing, a washing tub disposed in the water tank, a motor that rotationally drives the washing tub via a rotation axis in a substantially vertical direction, and a heating device that heats a washing liquid. A recess is formed at the bottom of the water tank so as to be lower than the bottom surface of the water tank, a heating plate that covers the heating device is provided above the heating device, and there is a gap between the side of the heating plate and the side surface of the recess.

Effects of the Invention

[0011] The washing machine according to the present invention can provide a washing machine capable of reducing the maintenance of a heating device.

Brief Description of the Drawings

[0012]

Figure 1

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Figure 14

Mode for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited by these embodiments.

[0014] FIG. 1 is an exploded perspective view of a washing machine according to an embodiment of the present invention as viewed from the back, and FIG. 2 is a longitudinal sectional view of the washing machine.

[0015] The housing 1 is formed in an L shape having a front surface, both side surfaces, and a back surface, and an opening 2 is formed on the back side. The opening 2 is closed by a door body 3 so as to be openable and closable. By removing the door body 3, the inside of the housing 1 can be viewed from the opening 2.

[0016] In the present embodiment, since the opening 2 is formed on the back side of the housing 1, the housing 1 is rotated to a position where the inside of the housing 1 can be maintained through the opening 2, and maintenance of the inside of the housing 1 is performed. By disposing the door body 3 on the back surface, it does not enter the user's field of view when the washing machine is installed and does not impair the aesthetics.

[0017] In the present embodiment, the opening 2 is formed on the back side of the housing 1, but it may be formed on the side surface. When formed on the side surface, the amount of movement of the housing 1 during maintenance can be reduced, and the inspection workability can be improved.

[0018] Above the housing 1, an upper case 4 is mounted. In the space surrounded by the housing 1 and the upper case 4, a bottomed cylindrical water tank 5 made of a flame-retardant synthetic resin is supported, and a rotary shaft 6 is disposed on the central axis of the water tank 5. Inside the water tank 5, a washing tub 7 connected to the rotary shaft 6 is installed, and at the bottom of the washing tub 7, a pulsator 8 connected to the rotary shaft 6 is disposed. Below the water tank 5, a motor 9 is disposed, the rotary shaft 6 is connected to the motor 9, and the washing tub 7 and the pulsator 8 are rotationally driven by the motor 9.

[0019] On the upper surface of the water tank 5, an inlet 10 for loading laundry into the washing tub 7 is formed, and the inlet 10 is openably and closably closed by a lid 11. In the upper case 4, an external inlet (not shown) for loading laundry into the washing tub 7 is formed, and the external inlet is openably and closably closed by an outer lid 12.

[0020] The washing tub 7 includes a cylindrical side wall 7a made of a corrosion-resistant metal, in this embodiment, stainless steel, and a bottom wall 7b made of a flame-retardant synthetic resin, and the side wall 7a and the bottom wall 7b are integrally fixed. The washing tub 7 is provided with a large number of dehydration holes 13 in the side wall 7a, and an annular fluid balancer 14 for reducing dehydration vibration is attached to the upper part.

[0021] On the washing tub 7, a circulation waterway cover 15 is provided at positions facing each other on the side wall 7a, and a circulation waterway (not shown) is formed between the side surface of the washing tub 7 and the circulation waterway cover 15. By mounting a pair of circulation waterway covers 15 on the washing tub 7, two opposing circulation waterways are formed. The circulation waterway cover 15 and the circulation waterway are preferably formed in the same shape in order to suppress the occurrence of imbalance during the rotation of the washing tub 7, but the shapes may be different if necessary.

[0022] On the circulation waterway cover 15, discharge ports 16 are formed at positions corresponding to the upper part and the middle part of the washing tub 7. The discharge ports 16 may be formed only at one of the positions corresponding to the upper part or the middle part of the washing tub 7.

[0023] At the lower part of the pulsator 8, blades 8a are integrally formed. When the motor 9 rotates the pulsator 8, the centrifugal force of the blades 8a pushes the washing water toward the outer peripheral side, circulating through the circulation water path, and discharging and spraying the washing liquid into the washing tub 7 from the discharge port 16 of the circulation water path.

[0024] At the bottom of the water tank 5, a recess 17 is formed in a substantially arc shape centered on the rotating shaft 6, and the bottom of the water tank 5 is formed to be inclined so as to gradually become lower toward the recess 17. A drain port 18 is formed at one end side of the recess 17 in the recess 17, and the bottom surface of the recess 17 is formed to be inclined so as to gradually become lower toward the drain port 18. The drain port 18 is formed at a position on the leading side in the rotation direction during dehydration of the washing tub 7 in the recess 17. The rotation direction during dehydration of the washing tub 7 is clockwise when viewed from above the washing tub 7, and is the A direction indicated by the arrow in FIG. 11.

[0025] In the recess 17 of the water tank 5, a mounting portion 20 for mounting the heating device 19 is integrally bulged upward from the bottom of the recess 17 of the water tank 5. The heating device 19 is for heating the washing water supplied into the water tank 5 and is composed of a heater.

[0026] The mounting portion 20 is formed across the recess 17 from the side surface of the water tank 5 and bulges upward from the bottom surface of the recess 17. The top surface of the mounting portion 20 is formed at substantially the same height as the bottom surface of the water tank 5 or slightly higher than the bottom surface of the water tank 5. The mounting portion 20 has a first side surface 20a that is substantially orthogonal to the rotation direction of the washing tub 7 and a second side surface 20b that is substantially orthogonal to the first side surface 20a. The first side surface 20a is configured to be inclined toward the rotation direction side of the washing tub 7 as it goes upward from the bottom surface side. The second side surface 20b is formed in a substantially vertical planar shape, and an opening 21 through which the heating device 19 is inserted from the outside of the water tank 5 is formed in the second side surface 20b.

[0027] The heating device 19 forms a heater wire in a meandering shape and fixes both end portions to a mounting plate 22 having an insulation and heat insulation function. A temperature sensor 23 composed of a thermistor is mounted on the mounting plate 22, and the temperature of the heating device 19 is detected by the temperature sensor 23. The temperature sensor 23 is disposed at a substantially central position of both end portions of the heater wire so as to accurately detect the temperature of the heating device 19. A sealing material (not shown) is provided on the outer peripheral portion of the mounting plate 22, and the mounting plate 22 is watertightly attached to the periphery of the opening 21 of the second side surface 20b of the mounting portion 20 by the sealing material.

[0028] The water tank 5 is mounted on the housing 1 such that the opening 21 of the mounting portion 20 faces the door body 3. When the door body 3 is opened, the opening 21 of the mounting portion 20 faces the opening 2 of the housing 1, and maintenance of the heating device 19 mounted on the opening 21 becomes possible.

[0029] A heat shield plate 24 formed of metal, stainless steel in this embodiment, is disposed below the heating device 19, and the heat shield plate 24 is fixed with a gap between the bottom surface of the recess 17. By disposing the heat shield plate 24 between the heating device 19 and the bottom surface of the recess 17, it is possible to suppress the heat generated by the heating device 19 from being directly transmitted to the recess 17, and it is possible to suppress the thermal deterioration of the bottom of the water tank 5.

[0030] In this embodiment, the heat shield plate 24 is formed of stainless steel in order to have corrosion resistance, but other metal materials may be used, and as long as it can suppress the conduction of heat of the heating device 19 to the water tank 5 and has flame retardancy or incombustibility, materials other than metals, for example, ceramics may be used.

[0031] Above the heating device 19, a heating plate 25 made of metal, stainless steel in this embodiment, is disposed. A through hole 25a is formed in the heating plate 25 on the center side of the water tank 5. The through hole 25a is formed at a position offset from the upper position of the heating device 19, and the heating device 19 is configured to be covered by the heating plate 25. Since the heating device 19 is covered by the heating plate 25, it is possible to suppress the direct transmission of heat generated from the heating device 19 to the washing tub 7, and it is possible to suppress the thermal degradation of the bottom of the washing tub 7.

[0032] The heating plate 25 is fixed while maintaining a space from the heating device 19 by a plurality of ribs 26 erected upward from the bottom surface of the recess 17. The heating plate 25 is mounted at substantially the same height as the bottom surface of the water tank 5 and the top surface of the mounting portion 20. The heating plate 25 is mounted so as to be inclined gradually higher toward the through hole 25a, and the washing liquid heated by the heating device 19 is efficiently guided to the through hole 25a by the inclination of the heating plate 25.

[0033] In this embodiment, the heating plate 25 is set to have an inclination angle of 3 degrees with respect to the horizontal. The washing machine of this embodiment is set to have an allowable inclination of 2 degrees with respect to the horizontal at the time of installation, and even when the washing machine is installed with a 2-degree inclination, the heating plate 25 is set to be inclined with respect to the ground surface.

[0034] The heating plate 25 is formed in a substantially rectangular shape, and the side 25b on the second side surface 20b side of the mounting portion 20, the side 25c on the outer peripheral side of the recess 17, and the side 25d on the center side of the recess 17 are respectively in contact with or close to the second side surface 20b, the outer peripheral side surface of the recess 17, and the center side surface of the recess 17. The side 25e on the rotation direction side of the washing tub 7 of the heating plate 25 has a space from the side surface of the recess 17, and the side 25f located between the center side surface of the recess 17 of the heating plate 25 and the second side surface 20b is formed in an arc shape and has a space between the center side surface of the recess 17 and the second side surface 20b.

[0035] The heating plate 25 is formed with a through hole 25g at a position above the temperature sensor 23. Since the washing liquid heated by the heating device 19 passes upward through the through hole 25g, the heated washing liquid does not stay around the temperature sensor 23, and the temperature sensor 23 can accurately detect the temperature of the washing liquid.

[0036] Near the heating device 19 in the recess 17, a circulation water port 32 is formed between the heat insulation plate 24 and the side wall of the recess 17. A circulation pump 27 is connected to the circulation water port 32, and one end of a circulation path 28 is connected to the circulation pump 27. The circulation path 28 is disposed outside the water tank 5, and the other end of the circulation path 28 is connected to a water injection port 29 formed near the input port 10. The washing liquid is supplied from the water injection port 29 above the washing objects in the washing tub 7 by the circulation pump 27.

[0037] The water injection port 29 is disposed above the discharge port 16 of the circulation water path. The circulation amount of the washing liquid by the circulation pump 27 is set to be larger than the circulation amount of the washing liquid in the circulation water path. As a result, the amount of the washing liquid supplied from the water injection port 29 is large and it is supplied from a high position. The supplied washing liquid hits the washing objects and the washing liquid in the washing tub 7 to foam, wrapping the washing objects with a large amount of foam and acting on the dirt, thereby improving the washing performance.

[0038] An operation display device 30 is disposed at the rear part of the upper surface of the upper case 4. By operating the operation display device 30, various operation courses are set and the set operation courses etc. are displayed. A control device 33 is disposed at a position facing the opening 2 of the housing 1, and the control device 33 executes the operation course selected by the operation display device 30.

[0039] In the present embodiment, the operation courses executed by the control device 33 include a course of heating the washing liquid to perform washing and a course of performing washing in a non-heated state of the washing liquid.

[0040] In the washing machine configured as described above, the operation and action thereof will be described below.

[0041] Open the outer lid 12 and the lid body 11, put the laundry into the washing tub 7 through the inlet 10, close the outer lid 12 and the lid body 11, and operate the power switch (not shown) of the operation display device 30 to turn on the power. Select an operation course or the like by the operation display device 30, and operate the start switch (not shown) to start the operation.

[0042] When the operation is started, after detecting the amount of the laundry put in, the water supply means (not shown) operates to start water supply, and the washing liquid is supplied into the water tank 5 together with the detergent put into the detergent case (not shown).

[0043] When a predetermined amount of washing liquid is stored in the water tank 5, the circulation pump 27 operates to inject the washing liquid from the water injection port 29 (see FIG. 3). Since the washing liquid from the water injection port 29 is supplied from a high position, it hits the laundry in the washing tub 7 to foam, and the foam penetrates deep into the fibers of the laundry, wraps the dirt, floats the dirt, and washes it off.

[0044] The amount of water supplied to the water tank 5 is set according to the amount of the laundry put into the washing tub 7. When a predetermined water level is detected by the water level sensor (not shown), the water supply stops, and the motor 9 is driven to rotate the pulsator 8 forward and reverse alternately. The rotation of the pulsator 8 stirs the laundry in the washing tub 7 together with the washing liquid to wash the laundry.

[0045] Even in the washing process, the operation of the circulation pump 27 continues. The foamed washing liquid is circulated to make the foam act on the dirt, and the dirt can be efficiently removed.

[0046] Continue the washing process for a predetermined time. When the washing is completed, open the drain valve (not shown) to drain the water. When the drainage is completed, perform dehydration. The dehydration is performed by rotating the washing tub 7 in one direction. In this embodiment, the washing tub 7 is rotated at high speed clockwise when viewed from above.

[0047] After dehydration, operate the water supply means to supply a predetermined amount of water to the washing tub 7, perform the rinsing process, and further perform the dehydration process to end each process of the washing.

[0048] When a course for heating the washing liquid to perform washing is selected as the driving course, in the washing step, a heating step for heating the washing liquid is performed. When the operation is started, the amount of the laundry put in is detected, and water is supplied into the water tank 5 according to the amount of the laundry put in. Along with the water supply, the heating device 19 is energized to heat the washing liquid in the water tank 5.

[0049] The washing liquid heated by the heating device 19 moves upward. Since the heating plate 25 located above the heating device 19 is disposed so as to be inclined gradually higher toward the through-hole 25a side, the heated washing liquid is guided along the heating plate 25 to the through-hole 25a and moves upward from the through-hole 25a above the heating plate 25.

[0050] Since the washing liquid below the heating plate 25 moves above the heating plate 25, the low-temperature washing liquid flows from around the heating plate 25 to the lower side of the heating plate 25. Since the heating plate 25 has a space between the side 25e on the rotation direction side of the washing tub 7, the side 25f located between the side surface on the center side of the recess 17 and the second side surface 20b, and the side surface of the recess 17, the washing liquid flows into the lower part of the heating plate 25 from the substantially opposite two sides of the heating plate 25. Since the washing liquid flows into the lower part of the heating plate 25 from the substantially opposite two sides of the heating plate 25, the washing liquid can be efficiently convected and the washing liquid can be efficiently heated. In addition, since the heating device 19 also heats the heating plate 25, the washing liquid is also heated by the heating plate 25, and the heating efficiency of the washing liquid is improved.

[0051] Since the through-hole 25a is formed in the inclined upper side of the heating plate 25, the heated washing liquid can be efficiently guided upward. The through-hole 25a is formed at a position laterally shifted from the upper position of the heating device 19, and since the upper part of the heating device 19 is covered by the heating plate 25, it is possible to prevent foreign matters from contacting the heating device 19 by the heating plate 25.

[0052] In the heating step, the washing liquid is heated by the heating device 19 to a predetermined temperature suitable for washing, which is about 15 °C in the present embodiment.

[0053] When the washing liquid reaches a constant temperature slightly lower than the predetermined temperature, the circulation pump 27 is activated to circulate the washing liquid and supply it from the water inlet 29 to the laundry. Since the warmed washing liquid is circulated, the powder detergent can be efficiently dissolved, the undissolved residue of the powder detergent can be suppressed, and the washing efficiency can be improved.

[0054] Since the washing liquid supplied from the water inlet 29 is supplied to the laundry from a high position, it foams when it hits the laundry, the foam penetrates into the laundry, and washes away the dirt attached deep inside the fibers. Since the washing liquid is warmed, the enzyme in the detergent is activated and the detergency can be improved.

[0055] When the washing liquid reaches the predetermined temperature, the pulsator 8 is rotated forward and backward alternately. By the rotation of the pulsator 8, the laundry in the washing tub 7 is stirred together with the washing water to wash the laundry. Since the washing liquid is heated and stirred, the undissolved residue of the powder detergent can be suppressed. Even in this state, the operation of the circulation pump 27 is continued to improve the washing efficiency.

[0056] When the pulsator 8 rotates, the washing liquid is pushed to the outer peripheral side by the centrifugal force generated by the rotation of the blades 8a, rises in the circulation water channel, and is sprinkled from the discharge port 16 toward the laundry in the washing tub 7.

[0057] Since the washing liquid sprinkled from the discharge port 16 to the laundry is heated to the predetermined temperature, the enzyme in the detergent is activated and the dirt soaked into the fibers of the laundry can be efficiently washed.

[0058] When the washing process with warm water is completed, a drain valve (not shown) is opened to drain the water. When the drainage is completed, dehydration is performed. The dehydration is performed by rotating the washing tub 7 in one direction, and in this embodiment, by rotating the washing tub 7 clockwise at a high speed when viewed from above.

[0059] After dehydration, the water supply means is activated to supply a predetermined amount of water to the washing tub 7, a rinsing process is performed, and then a dehydration process is performed to complete each washing process.

[0060] In the dehydration process, the washing tub 7 is rotated at high speed in the clockwise direction when viewed from above. Due to the rotation of the washing tub 7, an air flow is generated in the water tank 5 in the direction of arrow A shown in Fig. 11, and the dehydrated washing liquid flows together with the air flow.

[0061] The first side surface 20a of the mounting portion 20 is inclined toward the rotation direction side of the washing tub 7 as it goes upward. Therefore, the flow accompanying the rotation of the washing tub 7 is guided along the inclination of the first side surface 20a. Since the first side surface 20a is inclined, the suppression of the flow accompanying the rotation of the washing tub 7 from being blocked is achieved, the generation of turbulent flow is suppressed, and the generation of vibration is suppressed.

[0062] The second side surface 20b is formed substantially vertically for mounting the heating device 19. However, since it is located on the downstream side of the flow accompanying the rotation of the washing tub 7 compared to the first side surface 20a, it does not obstruct the flow and does not generate turbulent flow.

[0063] The upper part of the heating device 19 is covered by the heating plate 25. Furthermore, since the heating plate 25 is disposed at substantially the same height as the bottom surface of the water tank 5 and the top surface of the mounting portion 20, it does not obstruct the flow of the washing liquid flowing in the water tank 5 and can suppress the generation of turbulent flow.

[0064] The bottom surface of the water tank 5 is inclined toward the recess 17, and the bottom surface of the recess 17 is inclined toward the drain port 18. In the drainage process, the washing liquid in the water tank 5 flows toward the drain port 18. Since the heating device 19 is disposed at a position separated from the drain port 18, the washing liquid at the position facing the heating device 19 with respect to the rotary shaft 6 in the water tank 5 flows out from the drain port 18 without passing through the heating device 19. Since the amount of the washing liquid passing through the heating device 19 is reduced, the adhesion of lint contained in the washing liquid to the heating device 19 is suppressed.

[0065] When there is a problem with the heating device 19 or when maintenance of the heating device 19 is required, the washing machine is rotated to the position facing the door body 3, and the door body 3 is removed from the housing 1. Since the heating device 19 is disposed at a position facing the opening 2 from which the door body 3 has been removed, the heating device 19 can be visually recognized by removing the door body 3.

[0066] By removing the wiring from the terminals at both ends of the heating device 19 and removing the fixing screws (not shown), the heating device 19 can be removed from the water tank 5. The heating device 19 can be pulled out from the water tank 5 for maintenance. When replacing the heating device 19 with a new one, the new heating device 19 is inserted into the opening 21 of the mounting portion 20 of the water tank 5, the fixing screws are screwed in, the heating device 19 is fixed to the water tank 5, and the wiring is attached to the terminals of the heating device 19. The maintenance is completed by attaching the door body 3 to the housing 1 and returning the washing machine to its original position.

[0067] The bottom surface of the water tank 5 is inclined so as to gradually become lower toward the drain port 18, and the bottom surface of the water tank 5 is formed such that the outer peripheral side is the highest including the bottom surface of the recess 17. Reinforcing ribs 31 are formed on the back surface side of the bottom surface of the water tank 5 including the back surface of the recess 17. By raising the outer peripheral side of the back surface of the recess 17, the height of the reinforcing rib 31 located on the back surface of the recess 17 can be increased, and the strength of the recess 17 can be improved.

[0068] The heating device 19 is mounted substantially parallel to the bottom surface of the water tank 5 and is inclined such that the drain port 18 side is lower with respect to the horizontal plane. Since the heating device 19 is arranged substantially parallel to the bottom surface of the water tank 5, it is difficult to become a resistance to the drainage flowing toward the drain port 18, and it is possible to suppress the lint contained in the drainage from being entangled with the heating device 19.

[0069] In the present embodiment, the opening 2 is formed on the back side of the housing 1, but it may be formed on the side surface of the housing 1 with the heating device 19 facing the opening 2 on the side surface of the housing 1, or the opening 2 may be formed on the front surface of the housing 1 with the heating device 19 facing the opening 2 on the front surface of the housing 1.

[0070] By disposing the opening 2 on the side surface or the front surface of the housing 1, the amount of movement of the washing machine during maintenance can be reduced, and workability can be improved.

Industrial Applicability

[0071] As described above, since the washing machine according to the present invention can suppress the generation of vibration during the dehydration operation, it can also be applied to uses such as a washing and drying machine and an industrial washing machine.

Explanation of Reference Numerals

[0072] 1 Housing 2 Opening 3 Door body 5 Water tank 7 Washing tub 8 Pulsator 9 Motor 17 Recess 19 Heating device 20 Mounting portion 20a First side surface 20b Second side surface 21 Opening portion 23 Temperature sensor 24 Heat insulating plate 25 Heating plate 25a Through hole 27 Circulation pump 28 Circulation path 29 Water injection port

Claims

1. A housing, a water tank disposed within the housing, a washing tub disposed within the water tank, a motor that rotationally drives the washing tub via a substantially vertical rotation axis, a heating device that heats washing liquid, and is provided with, at the bottom of the water tank, a recess formed so as to be lower than the bottom surface of the water tank, above the heating device, a heating plate that covers the heating device is provided, a space is provided between the side of the heating plate and the side surface of the recess, a washing machine.

2. further comprising a drain port for draining the washing liquid in the water tank, the drain port is formed in the recess, vertically above the drain port is not covered by the heating plate, the washing machine according to Claim 1.

3. having the interval, the interval between the side close to the drain port and the side surface of the recess, and the interval between the side substantially opposite to the side close to the drain port and the side surface of the recess, the washing machine according to Claim 2.

4. at the bottom of the water tank, a mounting portion for mounting the heating device is further formed, the mounting portion has a first side surface that is substantially orthogonal to the rotation direction of the washing tub and into which the heating device is not inserted from the outside of the water tank, a space is provided between the end of the first side surface and the side surface of the recess, the washing machine according to any one of Claims 1 to 3.

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