CN111926523A

CN111926523A - Washing machine

Info

Publication number: CN111926523A
Application number: CN202010137865.8A
Authority: CN
Inventors: 北慎勇希; 吉田哲士; 小池敏文; 矢田好宏; 高田健太郎
Original assignee: Hitachi Global Life Solutions Inc
Current assignee: Hitachi Global Life Solutions Inc
Priority date: 2019-05-13
Filing date: 2020-03-03
Publication date: 2020-11-13
Anticipated expiration: 2040-03-03
Also published as: CN111926523B; JP2020185090A; JP7132173B2

Abstract

The invention provides a washing machine which reduces the shrinkage of clothes and reduces uneven drying. The drying process comprises the following steps: a standard drying step of drying at a predetermined temperature; and a low-temperature drying step of drying at a temperature lower than the predetermined temperature, wherein the low-temperature drying step includes heating the heating unit at a first intensity set in advance for a predetermined time, and heating the heating unit at a second intensity weaker than the first intensity after the elapse of the time or after the detection temperature of the temperature detection unit reaches the predetermined temperature before the elapse of the time, and turns off the heating unit when the detection temperature of the temperature detection unit reaches the first temperature set in advance, and turns on the heating unit after a predetermined time has elapsed after the turning off, and the turning off and on are repeated a plurality of times every elapse of the predetermined time after the turning on.

Description

Washing machine

Technical Field

The present invention relates to a washing machine having a drying operation function.

Background

Conventionally, there is known a washing machine equipped with a "drying operation program" of a known type for determining a degree of drying of laundry by detecting temperatures inside and outside a washing tub and drying the laundry by controlling a drying operation in accordance with the degree of drying. (for example, patent document 1). In order to raise the temperature inside the washing tub, wind generated by rotating the fan is circulated inside the washing tub via the PTC heater. The drying degree of the clothes is judged by observing the temperature difference between the inside and outside of the tub based on the principle that the temperature of the warm air rises when the moisture amount of the clothes decreases and the evaporation amount decreases, and the PTC heater is switched off if the temperature difference exceeds a threshold value, and the drying operation is ended.

Documents of the prior art

Patent document

Patent document 1: japanese laid-open patent publication No. 10-043499

Disclosure of Invention

Technical problem to be solved by the invention

In order to reduce the shrinkage of the laundry, it is very important to reduce the temperature in the tub as much as possible. Therefore, it is important to maintain the temperature in the tub lower than that when the PTC heater is continuously operated and low in order to reduce drying unevenness. Further, as a method of reducing the temperature in the tub, there is a method of reducing the resistance value of the PTC heater, but in view of mass productivity, series development, and cost, a method of not changing the resistance of the PTC heater is preferable.

The invention provides a washing machine which reduces the shrinkage of clothes and has less uneven drying.

Means for solving the problems

In order to solve the above problem, a washing machine according to the present invention includes, as an example: a water tub disposed inside the housing; a water supply part for supplying water to the water barrel; a heating part for heating air to obtain dry air; a blowing part for circulating the dry air; a temperature detecting part for detecting the temperature in the barrel or the temperature of the clothes; and a control unit having a drying step, the drying step including: a standard drying step of drying at a predetermined temperature; and a low-temperature drying step of drying at a temperature lower than the predetermined temperature, wherein the low-temperature drying step includes heating the heating unit at a first intensity set in advance for a predetermined time, and heating the heating unit at a second intensity weaker than the first intensity after the elapse of the time or after the detection temperature of the temperature detection unit reaches the predetermined temperature, and turns off the heating unit when the detection temperature of the temperature detection unit reaches the first temperature set in advance, and turns on the heating unit when the second temperature higher than the first temperature and lower than the predetermined temperature is reached, and turns on the heating unit after the elapse of the predetermined time after the turning off, and the turning off and on are repeated a plurality of times every elapse of the predetermined time after the turning on.

Effects of the invention

According to the present invention, it is possible to provide a washing machine that reduces the shrinkage of clothes and has less drying unevenness.

Drawings

Fig. 1 is a perspective view showing an external configuration of a washing machine according to the present invention.

Fig. 2 is a sectional view showing the structure of the washing machine of the present invention.

Fig. 3 is a diagram showing a control flow of the standard drying process of the present invention.

Fig. 4 is a diagram showing a control flow of the low-temperature drying step of the present invention.

Fig. 5 is a diagram showing the progression of the temperature inside the tub in the low-temperature drying step of the present invention.

Description of reference numerals

1: a washing machine; 2: a housing; 3: an outer tub (tub); 4: a water bucket; 5: an outer tub cover; 6: an inner cover; 7: an SUS plate; 8: rotating the leaf; 10: a main motor; 11: a rotation detecting device; 12: a motor current detection device; 13: a water supply unit; 14: a drying unit: (ii) a 15: a fan; 16: an air supply duct; 17: a drying pipeline; 18: a blow-out nozzle; 21: an upper face mask; 22: an outer cover; 23: a front panel; 24: an operation panel; 25: a recessed portion; 30: and a temperature measurer.

Detailed Description

Embodiments of the present invention (hereinafter referred to as "the present embodiments") will be described in detail below with reference to the drawings. The drawings are merely schematic drawings to the extent that the present invention can be fully understood. The invention is thus not limited to the examples shown in the figures. In the drawings, the same reference numerals are given to the common components (members) and the same components, and redundant description thereof will be omitted.

Hereinafter, embodiments of the present invention will be described with reference to fig. 1 to 5.

< external Structure of washing machine >

Hereinafter, an external structure of the washing machine 1 according to the present embodiment will be described with reference to fig. 1 to 2. Fig. 1 is a perspective view showing an external structure of a washing machine 1 according to the present embodiment. Fig. 2 is a sectional view showing the structure of the washing machine 1.

Here, the washing machine 1 is described as a washing and drying machine having a function of drying laundry (clothes). Here, the washing machine 1 is a vertical washing machine in which a vertical water tub is disposed inside a casing. However, the washing machine 1 may be a drum-type washing machine.

As shown in fig. 1, the washing machine 1 includes an upper cover 21 and an outer cover 22 that can be opened and closed freely on the upper surface of the casing 2. In the present embodiment, the washing machine 1 has a detachable front panel 23 on the front surface of the casing 2. The upper cover 21 is disposed on the rear upper surface of the housing 2. The outer cover 22 is disposed over the center of the housing 2. An operation panel 24 for operating the washing machine 1 is provided on the outer cover 22.

< internal Structure of washing machine >

The internal structure of the washing machine 1 will be described below with reference to fig. 2. Fig. 2 is a sectional view showing an internal structure of the washing machine 1.

As shown in fig. 2, the washing machine 1 has an outer tub 3 inside a casing 2, and a water tub 4 (washing and dehydrating tub) inside.

The outer tub 3 includes: an outer tub cover 5 provided on the upper surface; a lid member 5a sealing an opening portion provided in the tub cover 5; an inner lid 6 provided at the outer tub cover for taking out and putting in laundry; and a lid member 6a sealing the opening portion provided in the inner lid.

The water tub 4 (washing and dehydrating tub) has a bottomed cylindrical shape with an open upper surface. The water tub 4 has: an SUS plate 7 constituting a body portion of the cylinder; a rotary blade 8 rotating at the bottom of the water tub 4; a balancing ring 9 for maintaining the balance of the water tub 4. The SUS plate 7 is formed with a plurality of through holes 7a for water and air passage. The balance ring 9 is a fluid balancer in which fluid is sealed.

The washing machine 1 includes: a driving device 10 for rotationally driving the water tub 4 and the rotary blade 8; rotation detecting means 11 for detecting an operation of the driving means 10; and motor current detection means 12. The drive device 10 includes: a motor 10a for rotating the water tub 4 and the rotary blade 8; a clutch mechanism 10b that specifies the rotational direction and rotational speed of the water tub 4 and the rotary blade 8; and a rotating shaft 10c connected to the rotating blade 8. The rotation shaft 10c is disposed at the center of the water tub 4 in plan view.

In addition, the washing machine 1 includes, in a rear upper portion of the casing 2: a water supply unit 13 which is a water supply portion for supplying water to the water tub 4; a drying unit 14 having a heating portion such as a heater for heating air to obtain dry air; a fan 15 for circulating the drying air; an air supply duct 16; and a drying duct 17.

The air duct 16 is disposed between the fan 15 and the blowing nozzle 18, and the drying unit 14 is disposed at a midway portion thereof. The air supply duct 16 is connected to the blowout nozzle 18 via a bellows a 19. The blowing nozzle 18 blows the dry air heated by the drying unit 14 sent from the fan 15 into the tub 3. The drying duct 17 is disposed between the tub 3 and the fan 15. The drying duct 17 is connected to the recessed portion 25 of the tub 3 by a bellows B20.

The washing machine 1 has a control unit for performing a washing step, a rinsing step, and a drying step, and supplies water from the water supply unit 20 to the outer tub 3 for soaking the water tub 4 (washing and dehydrating tub) with water, for example, in the washing step and the rinsing step. In the drying process, for example, in washing machine 1, fan 15 is rotated to send air to air blowing duct 16, the air is heated by the heating part of drying unit 14 to obtain dry air, and the dry air is passed through outer tub 3 and water tub 4. Thereby, the washing machine 1 dries the washing target (clothes) accommodated in the water tub 4. The washing machine 1 repeatedly performs the same operation by sending the air having passed through the inside of the outer tub 3 and the water tub 4 from the drying duct 17 to the blowing duct 16 by the fan 15.

In addition, the washing machine 1 includes: a discharge path 26 through which water is discharged; and a drain valve 27 that opens and closes the drain path 26.

< brief summary of the present embodiment >

Hereinafter, a method of controlling the drying process according to the present embodiment will be described with reference to fig. 3 to 5.

The drying process comprises the following steps: a standard drying step (standard drying program) for performing a drying operation at a predetermined temperature (hereinafter, second predetermined temperature); and a low-temperature drying step (low-temperature drying program) for performing a drying operation at a temperature lower than the predetermined temperature (hereinafter, referred to as a second temperature).

Fig. 3 is a flowchart illustrating a normal drying process, fig. 4 is a flowchart illustrating a low-temperature drying process, and fig. 5 is a graph illustrating time and a tub interior temperature (or a laundry temperature) in the low-temperature drying process. However, the solid line in fig. 5 shows the value of the low-temperature drying step of the present invention, and the alternate long and short dash line shows the value of the standard drying step.

In the standard drying process, the PTC heater is operated for a predetermined time with the output of the PTC heater maximized (hereinafter, referred to as "strong operation (first intensity)), or the PTC heater is operated for a minimum output (hereinafter, referred to as" weak operation (second intensity)) after the temperature measured by the temperature measuring device 30 serving as the temperature detecting unit exceeds a predetermined value set in advance. The PTC heater output is minimized (hereinafter referred to as "weak operation (second intensity)) after the temperature in the tub measured by the temperature measuring device 30 as a temperature detecting unit reaches a first temperature which is a temperature at which the temperature in the tub is balanced. When the temperature in the tub measured by the temperature measuring device 30 reaches a second predetermined temperature, it is determined that the laundry is dried, and the PTC heater is turned off to end the operation. The second predetermined temperature is set to a temperature at which the laundry is completely dried. The second strength of the heating portion may be lower than the first strength.

In the case of the control of the standard drying process, when the operation is performed to the second predetermined temperature, the temperature in the tub becomes high, and the shrinkage of the laundry cannot be suppressed.

In the present invention, the second temperature is set to be lower than the second predetermined temperature, and the PTC heater as the heating portion is repeatedly turned on and off to keep the temperature in the tub constant with respect to the drying unevenness generated thereby, thereby suppressing the drying unevenness. Thus, the temperature in the barrel is lower than that in the standard drying process of the drying operation. In addition, the first temperature is the same in the standard drying process and in the low-temperature drying process.

Specifically, the control of the low-temperature drying step of the present invention will be described with reference to fig. 4.

After the drying is started, the heating unit is operated at the first intensity for a predetermined time, or operated until the temperature in the tub measured by the temperature measuring device 30 before the operation for the predetermined time exceeds a predetermined value, and then operated at the second intensity. Then, when the first temperature (predetermined temperature), which is the temperature at which the temperature in the tub measured by the temperature measuring device 30 as the temperature detecting section is balanced, is set as a reference value (for example, 60 ℃), and then the temperature in the tub measured by the temperature measuring device 30 reaches a second temperature (a second predetermined temperature or less) (for example, 65 ℃) higher than the first temperature, the PTC heater is turned off even if the laundry is not dried. After a preset Amin is passed since the heater is turned off, the heater is turned on, the heating part is operated at a second intensity, and the heater is turned off after a preset B min. After this routine (cycle) is executed a predetermined number of times (C times), the heater is turned off and the operation is ended. The values of a and B, C are values that can be changed as appropriate.

Fig. 5 shows the evolution of the output power of the PTC heater when the control of fig. 4 is performed. The output power shown in fig. 5 has a relationship proportional to the temperature inside the tub, depending on the intensity or the amount of current flowing when it is turned on/off.

By repeatedly turning on and off the heater in this way, the temperature in the tub can be kept low, and uneven drying can be suppressed.

As described above, according to the present invention, it is possible to provide a washing machine capable of suppressing uneven drying while suppressing reduction in size of laundry.

Claims

1. A washing machine, characterized by comprising:

a housing;

a water tub disposed inside the case;

a water supply part for supplying water to the water barrel;

a heating part for heating air to obtain dry air;

a blowing part for circulating the dry air;

a temperature detecting part for detecting the temperature in the barrel or the temperature of the clothes; and

a control part having a drying process is provided,

the drying process includes: a standard drying step of drying at a predetermined temperature; and a low-temperature drying step of drying at a temperature lower than the predetermined temperature,

the low-temperature drying step includes heating the heating unit at a first intensity set in advance for a predetermined time, heating the heating unit at a second intensity weaker than the first intensity after the time elapses or after a detection temperature of the temperature detection unit reaches a predetermined temperature before the time elapses, turning off the heating unit when the detection temperature of the temperature detection unit reaches the first temperature set in advance, and turning on the heating unit when a second temperature higher than the first temperature and lower than the predetermined temperature elapses after the turning off, and repeating the turning off and on a plurality of times every elapse of a predetermined time after the turning on.

2. A washing machine as claimed in claim 1, wherein:

the first temperature is the same in the standard drying process and the low-temperature drying process.