# US 9,435,587 B2 · Clothing dryer and blockage detection method thereof

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 9,435,587 B2
- Document ID: US9435587B2
- Status: Granted
- Kind: B2
- Application number: 13/851,319
- Filed: 2013-03-27
- Published: 2013-10-03
- Granted: 2016-09-06
- Earliest claimed: 2012-03-30
- Assignees: Samsung Electronics Co., Ltd.
- Applicants: Samsung Electronics Co., Ltd.
- Inventors: Hyung Woo Lee; Hee Beom Park; Sang Oh Yoo; Geun Kang; Pil Soo Chang
- Web page: https://patentgrep.com/patent/US9435587B2

## CPC

- D06F 34/20: Parameters relating to constructional components, e.g. door sensors
- D06F 58/50: Responding to irregular working conditions, e.g. malfunctioning of blowers
- F26B 25/009: {Alarm systems; Safety systems, e.g. preventing fire and explosions (using inert gases F26B21/40)}
- G01K 13/02: for measuring temperature of moving fluids or granular materials capable of flow
- D06F 37/42: Safety arrangements, e.g. for stopping rotation of the receptacle upon opening of the casing door
- D06F 58/20: General details of domestic laundry dryers (D06F59/00 takes precedence)
- D06F 58/22: Lint collecting arrangements
- D06F 2101/20: Operation modes, e.g. delicate laundry washing programmes, service modes or refreshment cycles
- D06F 2103/08: Humidity
- D06F 2103/32: Temperature
- D06F 2103/38: Time, e.g. duration
- D06F 2105/28: Electric heating
- D06F 2105/58: Indications or alarms to the control system or to the user
- G01K 13/024: of moving gases
- G01K 2207/00: Application of thermometers in household appliances
- D06F: LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
- F26B: DRYING SOLID MATERIALS OR OBJECTS BY REMOVING LIQUID THEREFROM (drying devices for combines A01D41/133; racks for drying fruit or vegetables A01F25/12; drying foodstuffs A23; drying hair A45D20/00; body-drying implements A47K10/00; drying household articles A47L; drying gases or vapours B01D; chemical or physical processes for dewatering or like separating liquids from solids B01D43/00; centrifugal apparatus B04; drying ceramics C04B33/30; drying yarns or fabrics in association with some other form of treatment D06C; drying frames for laundry without heating or positive air circulation, domestic laundry-or spin-driers, wringing or hot pressing laundry D06F; furnaces, kilns, ovens F27)
- G01K: MEASURING TEMPERATURE; MEASURING QUANTITY OF HEAT; THERMALLY-SENSITIVE ELEMENTS NOT OTHERWISE PROVIDED FOR (radiation pyrometry G01J5/00)

## Abstract

A method for detecting a degree of blockage of an exhaust duct includes detecting the temperature of air in an intake and exhaust system, calculating a rate of change of the detected temperature, and determining a degree of blockage of the exhaust duct based on the detected temperature and the rate of change of the detected temperature.

## Claims

### Claim 1

A dryer, comprising:
a drum to accommodate a substance to be dried;
a temperature sensor to detect a temperature at an entry of hot air into the drum;
a heater to supply the hot air to the inside of the drum;
an exhaust duct to discharge the hot air passed through the drum;
a thermostat to control power applied to the heater while operating according to a temperature of the heater; and
a control unit configured to detect a degree of a blockage of the exhaust duct based on the detected temperature at the entry of hot air into the drum and an operation of the thermostat,
wherein the temperature sensor is a thermistor to detect the temperature of the hot air being introduced to the inside of the drum,
wherein the control unit, when a rate of temperature change of the thermistor exceeds a reference rate of change at a predetermined point in time, determines the point in time as a point in time of the operation to detect the temperature of the entry of the drum and the time, and
wherein the point in time of the operation comprises a first point in time of the operation when the heater is turned OFF according to the operation of the thermostat, and a second point in time of the operation when the heater is turned ON after being turned OFF according to the operation of the thermostat.

### Claim 2 (depends on 1)

The dryer of claim 1, wherein:
the thermistor is provided at a hot blast duct configured to introduce hot air to the inside of the drum.

### Claim 3 (depends on 1)

The dryer of claim 1, wherein:
the first point in time of the operation is a point in time when a temperature of the entry of the drum detected by the thermostat is provided with a maximum value.

### Claim 4 (depends on 3)

The dryer of claim 3, wherein:
the second point in time of the operation is a point in time when the temperature of the entry of the drum detected by the thermostat is provided with the minimum value.

### Claim 5 (depends on 4)

The dryer of claim 4, wherein:
the control unit is configured to calculate a temperature difference between the maximum temperature at the first point in time of the operation and the minimum temperature at the second point in time of the operation, calculate a time difference between a time at the first point in time of the operation and a time at the second point in time of the operation, and detect the degree of the blockage of the exhaust duct by using the temperature difference and the time difference that are calculated.

### Claim 6 (depends on 5)

The dryer of claim 5, wherein:
the control unit stores a table capable of calculating the degree of the blockage of the exhaust duct by use of the temperature difference and the time difference.

### Claim 7 (depends on 6)

The dryer of claim 6, wherein:
the control unit is configured to detect the degree of the blockage of the exhaust duct at each stage level based on data stored in the table.

### Claim 8 (depends on 1)

The dryer of claim 1, wherein:
the control unit is configured to display the detected degree of the blockage of the exhaust duct at each stage level with a display unit.

### Claim 9 (depends on 8)

The dryer of claim 8, wherein:
in a case that the display unit is a liquid crystal display (LCD), the display unit is configured to display different warning messages in the form of text based on the degree of a blockage of the exhaust duct.

### Claim 10 (depends on 9)

The dryer of claim 9, wherein:
the display unit is configured to display the warning message in a form of an expression of emphasis including at least one of colorization, boldfacing, and italicization, or in a continuous manner for a predetermined period of time.

### Claim 11 (depends on 8)

The dryer of claim 8, wherein:
in a case that the display unit is a light emitting diode (LED), the display unit is configured to display a blockage icon by lighting or flashing the blockage icon based on the degree of the blockage of the exhaust duct.

### Claim 12 (depends on 11)

The dryer of claim 11, wherein:
the display unit is configured to continuously displaying the blockage icon for a predetermined period of time.

### Claim 13 (depends on 1)

The dryer of claim 1, wherein:
the thermostat is a safety apparatus installed at a side surface or adjacent to the heater and configured to mechanically operate based on the temperature of the heater.

### Claim 14 (depends on 1)

The dryer of claim 1, wherein:
the exhaust duct comprises a front exhaust duct and a rear exhaust duct to guide the discharging of the air that is passed through the drum, and an outside exhaust duct connected to the rear exhaust duct to guide the discharged air to an outdoor location.