EP3041986B1

EP3041986B1 - Improved ironing board for use with a cordless clothes iron

Info

Publication number: EP3041986B1
Application number: EP13759476.8A
Authority: EP
Inventors: Ahmet Yorukoglu; Onur Yaman; Sefa Hazir; Yagiz TEZEL; Ahmet SOZEN
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2013-09-02
Filing date: 2013-09-02
Publication date: 2017-11-01
Anticipated expiration: 2033-09-02
Also published as: WO2015028102A1; CN105492687A; EP3041986A1; ES2657952T3

Description

The present invention relates to an ironing board and a cordless clothes iron for use with the ironing board. The present invention more particularly relates to an ironing board which inductively operates a cordless clothes iron.
A clothes iron is usually equipped with an electrical resistance utilized for heating a sole plate. The electric power needed for operating the electrical resistance is typically supplied by an electric power cord in other words by a flexible electric wire which is connectable to a mains supply. The electric power cord is a simple and reliable means for transmitting electric power to a clothes iron. However, an electric power cord has also several drawbacks. For instance, an electric power cord generally restricts a user's actions when ironing the clothes. In addition, an electric power cord is also a potential for accidents. These and similar drawbacks have been overcome by the so-called "cordless" clothes irons.
Several techniques have been devised for operating a cordless clothes iron. In a commonly known technique, the ironing board is equipped with an electric socket which is mounted on an iron rest. The cordless clothes iron is equipped with an electric plug. When the cordless clothes iron is placed on the iron rest by the user, the electric plug easily fits into the electric socket. Thereby, the cloths iron becomes easy to handle. However, the user must from time to time interrupt ironing the clothes for re-heating the sole plate on the iron rest. Hence, a time spent for the ironing work increases.
In another commonly known technique, plural induction coils are installed under the ironing board. The cordless clothes iron is equipped with a sole plate which is made from a material having a high magnetic permeability such as a ferromagnetic material.
The induction coils which are installed under the ironing board, generate an electromagnetic field which induces electric currents in the sole plate. Thereby, the sole plate is inductively heated.
DE 199 04 587 A1 discloses an ironing board and a cordless clothes iron which has a sole plate made of ferritic steel. The ironing board includes a table for ironing clothes thereon, plural induction coils arranged underneath the table for inductively heating the sole plate and a control unit for energizing the induction coils.
In general, cordless cloths irons which are operable on ironing boards by inductive power transmission greatly facilitate ironing. However, such inductive-type ironing systems have several drawbacks.
A cordless induction-type clothes iron generally requires powerful induction coils to effectuate satisfactory heating of the sole plate. However, a provision and installation of such powerful induction coils into the ironing board incurs relatively high costs. Moreover, the ironing board becomes relatively heavy. Consequently, the user is likely to have difficulties in folding and stowing the ironing board.
An objective of the present invention is to provide an ironing board which overcomes the aforementioned problems and which efficiently and reliably operates a cordless clothes iron by inductive power transmission.
This objective has been achieved by the ironing board according to the present invention as defined in claim 1, and the ironing system according to the present invention as defined in claim 11. Further achievements have been attained by the subject-matters respectively defined in the dependent claims.
In the ironing board according to the present invention, the induction coil is movably supported along the entire table. The position of the cordless clothes iron, relative to the table is determined by sensing the cordless clothes iron. The induction coil is displaced in accordance with the determined position. Thereby, a single induction coil can be effectively utilized to operate the cordless clothes iron, by inductive power transmission, at any point on the table.
In an embodiment, a load of the induction coil is monitored to decide whether the cordless clothes iron is present or absent above the induction coil. In this embodiment, the induction coil is energized in accordance with the decision on the presence-absence. Thereby, energy efficiency and reliability of the ironing system have been further improved.
In another embodiment, the induction coil is displaced to a home position if it is decided that the cordless clothes iron has been absent above the induction coil for more than a predetermined duration.
In another embodiment, energizing of the induction coil is gradually reduced and finally stopped when the cordless clothes iron does not substantially change its position on the table for a predetermined duration. In this embodiment, energizing of the induction coil is resumed with the previously set operation mode defining a target temperature, when the cordless cloth iron restarts moving.
In another embodiment, load cells are utilized for sensing the cordless clothes iron. The load cells respectively sense a force exerted by the cordless clothes iron when being pressed onto the table. Thereby, a position of the cordless clothes iron relative to the table is precisely determined based on the distribution and the strength of the sensed forces.
In another embodiment, the induction coil is mounted onto a carriage which is movably guided along the entire table. The carriage is moved and stopped by an actuator in accordance with a position of the cordless clothes iron. Thereby, the induction coil can be precisely displaced to a position underneath the cordless clothes iron.
In another embodiment, the induction coil is protected from excessive heat radiated off from the table, by means of an air gap which is left between the table and the induction coil.
In another embodiment, the induction coil is prevented from overheating by monitoring its temperature.
In another embodiment, the induction coil is energized in accordance with control information which is wirelessly received from the cordless clothes iron, to precisely maintain a temperature of the sole plate at a target temperature.
In another embodiment, the cordless clothes iron wirelessly transmits control information for controlling operation of the induction coil of the ironing board in accordance with a target temperature input by a user and a temperature of the sole plate. In this embodiment, a plurality of operation modes respectively defined by a different target temperature are available for the purpose of ironing clothes made of different kinds of material.
In another embodiment, the target temperature is automatically selected by the cordless clothes iron. In this embodiment, the ironing board transmits the temperature of the induction coil to the cordless clothes iron. The cordless clothes iron switches to operation modes by comparing the temperature of the sole plate with the temperature of the induction coil. In this embodiment, the cordless clothes iron wirelessly transmits control information for controlling operation of the induction coil (4) in accordance with the target temperature defined for the switched mode and the temperature of the sole plate.
In another embodiment, the cordless clothes iron audibly and/or visually outputs information to the user.
In another embodiment, the sole plate is rendered exchangeable.
In another embodiment of the cordless clothes iron, the thermal energy needed for producing steam is obtained from the inductively heated the sole plate.
Additional advantages of the ironing system according to the present invention will become apparent with the detailed description of the embodiments with reference to the accompanying drawings in which:

Figure 1 - is a schematic side view of an ironing system including an ironing board and a cordless clothes iron according to an embodiment of the present invention.
Figure 2 - is a schematic top view of the ironing system including the ironing board and the cordless clothes iron according to an embodiment of the present invention.
Figure 3 - is a schematic cross sectional view taken along the line A - A in Fig. 1.
Figure 4 - is a schematic cross sectional view taken along the line B - B in Fig. 2.

The reference signs appearing on the drawings relate to the following technical features.

1.: Ironing board
2.: Cordless clothes iron
3.: Table
4.: Induction coil
5.: First control unit
6.: Guide
7.: Carriage
8.: Iron rest
9.: Heat-resistant fabric
10.: Gap
11.: Temperature sensor
12.: Ironing system
13.: Sole plate
14.: User interface unit
15.: Temperature sensor
16.: Leg
17.: Hinge
18.: Motor
19.: Screw
20.: Bearing
21.: Encoder
22.: Limit switch

The ironing board (1) is suitable for use with a cordless clothes iron (2) (Fig. 1). The ironing board (1) comprises a table (3) for ironing clothes thereon, an induction coil (4) for generating a time-varying electromagnetic field and a first control unit (5) for controlling operation of the induction coil (4) (Fig.4).
The ironing board (1) according to the present invention further comprises a support unit which movably supports the induction coil (4) along the entire table (3) and a first sensor unit (not shown) which senses the cordless clothes iron (2) and outputs a signal to the first control unit (5) (Fig. 4). The first control unit (5) determines a position of the cordless clothes iron (2) relative to the table (3) based on the signal, and operates the support unit to displace the induction coil (4) in accordance with the determined position (Fig. 4).
In an embodiment of the present invention, the first control unit (5) determines presence-absence of the cordless clothes iron (2) on the induction coil (4) by measuring a load of the induction coil (4), and controls operation of the induction coil (4) in accordance with the determination result on the presence-absence (Fig. 4). In this embodiment, the load is monitored by measuring a voltage across the induction coil (4) and a current flowing through the induction coil (4) (Fig. 3).
In an alternative embodiment of the present invention, the load is monitored by measuring and comparing a phase of the voltage across the induction coil (4) and a phase of the current flowing through the induction coil (4) (Fig. 3).
In another embodiment of the present invention, the first control unit (5) operates the support unit to displace the induction coil (4) to a home position if the cordless clothes iron (2) is absent on the induction coil (4) for more than a first predetermined duration. In this embodiment, monitoring of the load is continued during the absence of the cordless clothes iron (2) and the induction coil (4) is also not moved prior to expiry of the first predetermined duration. However, if it is decided that the cordless clothes iron (2) is again present on the induction coil (4) prior to expiry of the first predetermined duration, energizing of the induction coil (4) is resumed with the previously set operation mode for heating the sole plate (13).
In another embodiment of the present invention, the first control unit (5) terminates operation of the induction coil (4) if it is determined that a position of the cordless clothes iron (2) does not change for more than a second predetermined duration. In this embodiment, the first control unit (5) resumes, after expiry of the second predetermined duration, operation of the induction coil (4) with the previous operation mode, if it is determined that a position of the cordless cloth iron (2) changes. In this embodiment, the cordless clothes iron (2) has a non-volatile memory (not shown) such as an EEPROM for storing the set operation mode.
In another embodiment of the present invention, the first sensor unit includes at least three load cells (not shown) which are arranged on the table (3). Each of the load cells senses a force exerted by the cordless clothes iron (2). In this embodiment, the first control unit (5) determines a position of the cordless clothes iron (2) relative to the table (3) based on a spatial distribution and strength of the sensed forces, for example, by referring to a look-up table (LUT) or by way of direct calculation.
In another embodiment of the present invention, the three load cells are respectively arranged on the sides of the table (3).
In an alternative embodiment of the present invention, optical and/or acoustical sensors (not shown) are used to track the position of the cordless clothes iron (2).
In another embodiment of the present invention, the support unit includes a guide (6) which is arranged along the table (3), on its lower side and a carriage (7) which is movably engaged with the guide (6) (Figs. 3 and 4). The induction coil (4) is fixed onto the carriage (7) (Figs. 3 and 4). The support unit further includes an actuator which displaces the carriage (7) along the guide (6) (Figs. 3 and 4). The first control unit (5) operates the actuator to displace the carriage (7) in accordance with the determined position (Figs. 3 and 4). In this embodiment, the position of the carriage (7) is determined by utilizing an encoder (21) which is built into or attached to the actuator (Figs. 3 and 4).
In another embodiment of the present invention, the actuator includes an electric motor (18) and a screw (19) rotatably connected to the motor (18) (Figs. 3 and 4). The screw (19) is supported by a couple of bearings (20) arranged along the long axis (LA) of the table (3). In this embodiment, the encoder (21) is located on the screw (19). In addition, limit switches (22) are arranged on the opposing ends of the guide (6) (Fig. 3).
In another alternative embodiment of the present invention, the position of the carriage (7) is determined by utilizing a resolver (not shown) which is built into or attached to the actuator.
In another embodiment of the present invention, a single induction coil (4) is mounted onto the carriage (7) (Fig. 3). In this embodiment, the induction coil (4) has an oblong shaped winding which extends along the entire width (W) of the table (3).
In another embodiment of the present invention, the ironing board (1) further comprises an iron rest (8) for supporting the cordless clothes iron (2) (Fig. 1 to 4). In this embodiment, the table (3) is made from a heat-resistant and non-magnetic material, preferably plastic (Fig. 1). In this embodiment, the table (3) is covered with a heat-resistant fabric (9) (Fig. 2). In addition, a gap (10) is provided between a lower side of the table (3) and an upper side of the induction coil (4) (Fig. 4).
In another embodiment of the present invention, the table (3) is height-adjustable and has foldable legs (16) which are pivotably connected to each other by one or more hinges (17).
In another alternative embodiment of the present invention, the table (3) is made from wood, glass, ceramic, or non-magnetic steel, or a non-magnetic and metallic material such as aluminum and the like.
In another embodiment of the present invention, the iron rest (8) has an eye-catching design which differs in structure and shape from the rest of the ironing board (1) so as to be easily noticed by the user (Fig. 3). In this embodiment, the iron rest (8) has a recess portion for securely supporting the cordless clothes iron (2). In this embodiment, the home position of the induction coil (4) is a mid-position underneath the table (3).
In another embodiment of the present invention, the ironing board (1) further comprises a second sensor unit which includes a temperature sensor (11), for sensing a temperature of the induction coil (4) and outputting the sensed temperature to the first control unit (5) (Figs. 3 and 4). In this embodiment, the first control unit (5) compares the sensed temperature of the induction coil (4) with a threshold temperature, and controls operation of the induction coil (4) in accordance with the comparison result. In this embodiment, energizing of the induction coil (4) is suppressed or terminated when the sensed temperature of the induction coil (4) exceeds the threshold temperature.
In another embodiment of the present invention, the temperature sensor (11) of the second sensor unit is embedded in a center portion of the induction coil (4) (Figs. 3 and 4).
In another embodiment of the present invention, the ironing board (1) further comprises a first wireless communication unit (not shown) which establishes communication with the cordless clothes iron (2) to receive control information. In this embodiment, the first control unit (5) controls operation of the induction coil (4) in accordance with the received control information.
In another embodiment of the present invention, the ironing board (1) establishes a one-way wireless communication with the cordless clothes iron (2). In this embodiment, the ironing board (1) and the cordless clothes iron (2) respectively utilizes an RF receiver (not shown) and an RF transmitter (not shown).
In another alternative embodiment of the present invention, the ironing board (1) and the cordless clothes iron (2) respectively utilizes an IR receiver (not shown) and an IR transmitter (not shown) to establish a one-way wireless communication.
In another embodiment of the present invention, the ironing board (1) establishes a two-way wireless communication with the cordless clothes iron (2). In this embodiment, both the ironing board (1) and the cordless clothes iron (2) utilize an RF receiver (not shown) and an RF transmitter (not shown).
In another alternative embodiment of the present invention, both the ironing board (1) and the cordless clothes iron (2) utilize an IR receiver (not shown) and an IR transmitter (not shown) to establish a two-way wireless communication.
In another embodiment of the present invention, the first control unit (5) operates the first wireless communication unit to transmit the sensed temperature of the induction coil (4) to the cordless clothes iron (2).
The ironing system (12) comprises the ironing board (1) and a cordless clothes iron (2) (Figs. 1 to 4).
The cordless clothes iron (2) according to the present invention comprises a sole plate (13) made from a material suitable for induction heating, a user interface unit (14) for receiving a user input to set an operation mode of the cordless clothes iron (2), wherein the operation mode is defined through at least a target temperature for the sole plate (13), a third sensor unit which includes a temperature sensor (15), for sensing a temperature of the sole plate (13) and for outputting the sensed temperature, a second wireless communication unit (not shown) for establishing communication with the ironing board (1) to transmit control information for controlling operation of the induction coil (4) in accordance with the target temperature and temperature of the sole plate (13), a second control unit (not shown) for controlling operation of the user interface unit (14), the third sensor unit, and the second wireless communication unit and a power supply unit (not shown) which includes a receiver coil for sensing a time-varying magnetic field of the induction coil (4), a rectifier and a regulator which are electrically connected to the receiver coil to output an operating voltage for the overall operation of cordless clothes iron (2) (Fig. 4).
In another embodiment of the present invention, the second control unit has a plurality of operation modes respectively defined by a different target temperature for ironing clothes made of different kinds of material. In this embodiment, the second control unit compares the temperature of the sole plate (13) and the temperature of the induction coil (4), and determines a kind of the cloth being ironed based on the comparison result, for example, by referring to a look-up table (LUT). Subsequently, the second control unit switches to an operation mode in accordance with its determination result on the kind of cloth. The second wireless communication unit transmits control information for controlling operation of the induction coil (4) in accordance with the target temperature of the switched operation mode and the temperature of the sole plate (13).
In another embodiment of the present invention, the user interface unit (14) has means which is respectively configured to audibly and/or visually output information to the user. In this embodiment, the information includes at least one of a target temperature, a temperature of the sole plate (13), and an operation mode input by the user or switched to by the second control unit. In this embodiment, LEDs (not shown) and/or a display (not shown) are utilized to output, for example, a temperature of the sole plate to the user. In this embodiment, the cordless clothes iron (2) has a button (not shown) for setting a target temperature of the sole plate and/or a clothes type.
In another embodiment of the present invention, the sole plate (13) has an optimum size and shape for performing the ironing work.
In another alternative embodiment of the present invention, the sole plate (13) is rendered exchangeable. In this embodiment, the user can mount onto the cordless clothes iron (2), a sole plate (13) which has a shape and size that is either suitable fast ironing or detailed ironing.
In another embodiment of the present invention, the cordless clothes iron (2) has a water reservoir (not shown) which is arranged in thermal contact with the sole plate (13). The sole plate (13) has one or more than one discharge opening (not shown) which is in fluid communication with the water reservoir via a valve (not shown), for densely ejecting steam onto the clothes. The cordless clothes iron (2) has a button (not shown) for operating the valve.

Claims

An ironing board (1) suitable for use with a cordless clothes iron (2), comprising a table (3) for ironing clothes thereon an induction coil (4) for generating a time-varying electromagnetic field and a first control unit (5) for controlling operation of the induction coil (4), characterized in that a support unit configured to movably support the induction coil (4) along the table and a first sensor unit for sensing the cordless clothes iron (2) and outputting a signal to the first control unit (5), wherein the first control unit (5) is configured to determine a position of the cordless clothes iron (2) relative to the table (3) based on the signal, and to operate the support unit to displace the induction coil (4) in accordance with the determined position.
The ironing board (1) according to Claim 1, characterized in that the first control unit (5) is further configured to determine presence-absence of the cordless clothes iron (2) on the induction coil (4) by measuring a load of the induction coil (4), and to control operation of the induction coil (4) in accordance with the determination result on the presence-absence.
The ironing board (1) according to Claim 2, characterized in that the first control unit (5) is further configured to operate the support unit to displace the induction coil (4) to a home position if the cordless clothes iron (2) is absent on the induction coil (4) for more than a first predetermined duration.
The ironing board (1) according to any one of claims 1 to 3, characterized in that the first control unit (5) is further configured to terminate operation of the induction coil (4) if it is determined that a position of the cordless clothes iron (2) does not change for more than a second predetermined duration, and to resume, after expiry of the second predetermined duration, operation of the induction coil (4) if it is determined that a position of the cordless cloth iron (2) changes.
The ironing board (1) according to any one of claims 1 to 4, characterized in that the first sensor unit includes at least three load cells arranged on the table (3), each for sensing a force exerted by the cordless clothes iron (2), wherein the first control unit (5) is configured to determine the position of the cordless clothes iron (2) based on the sensed forces.
The ironing board (1) according to any one of claims 1 to 5, characterized in that the support unit includes,
- a guide (6) arranged along the table (3), on a lower side thereof,

- a carriage (7) movably engaged with the guide (6), wherein the induction coil (4) is fixed onto the carriage (7) and

- an actuator configured to displace the carriage (7) along the guide (6), wherein the first control unit (5) is configured to operate the actuator to displace the carriage (7) in accordance with the determined position.
The ironing board (1) according to any one of claims 1 to 6, characterized in that an iron rest (8) for supporting the cordless clothes iron (2), wherein the table (3) is made from a heat-resistant and non-magnetic material and is covered with a heat-resistant fabric (9) and wherein a gap (10) is provided between the induction coil (4) and the table (3).
The ironing board (1) according to any one of claims 1 to 7, characterized in that a second sensor unit including a temperature sensor (11), for sensing a temperature of the induction coil (4) and for outputting the sensed temperature to the first control unit (5), wherein the first control unit (5) is further configured to compare the sensed temperature of the induction coil (4) with a threshold temperature and to control operation of the induction coil (4) in accordance with the comparison result.
The ironing board (1) according to any one of claims 1 to 8, characterized in that a first wireless communication unit for establishing communication with the cordless clothes iron (2) to receive control information, wherein the first control unit (5) is further configured to control operation of the induction coil (4) in accordance with the received control information.
The ironing board (1) according to of Claim 9, characterized in that the first control unit (5) is further configured to operate the first wireless communication unit to transmit the sensed temperature of the induction coil (4) to the cordless clothes iron (2).
An ironing system (12) comprising the ironing board (1) according to claim 9 or 10 and the cordless clothes iron (2) characterized in that said cordless clothes iron (2) comprising
- a sole plate (13) made from a material suitable for induction heating,

- a user interface unit (14) for receiving a user input to set an operation mode of the cordless clothes iron (2), the operation mode is defined through at least a target temperature for the sole plate (13),

- a third sensor unit including a temperature sensor (15), for sensing a temperature of the sole plate (13) and for outputting the temperature of the sole plate (13),

- a second wireless communication unit for establishing communication with the ironing board (1) to transmit control information for controlling operation of the induction coil (4) in accordance with the target temperature and the output temperature of the sole plate (13),

- a second control unit for controlling operation of the user interface unit (14), the third sensor unit, and the second wireless communication unit and

- a power supply unit including a receiver coil for sensing a time-varying magnetic field of the induction coil (4), a rectifier and a regulator electrically connected to the receiver coil to output an operating voltage.
The ironing system (12) according to claim 11, characterized in that the second control unit has a plurality of operation modes respectively defined by a different target temperature for ironing clothes made of different kinds of material, wherein the second control unit is configured to compare the temperature of the sole plate (13) and the temperature of the induction coil (4), to determine a kind of the cloth being ironed based on the comparison result, and to switch to an operation mode in accordance with the determination result on the kind of cloth.
The ironing system (12) according to claim 12, characterized in that the user interface unit (14) has means respectively configured to audibly and/or visually output information to the user, wherein said information includes at least one of a target temperature, a temperature of the sole plate (13) and an operation mode.
The ironing system (12) according to any one of claims 11 to 13, characterized in that the cordless clothes iron (2) has an exchangeable sole plate (13).
The ironing system (12) according to any one of claims 11 to 14, characterized in that the cordless clothes iron (2) further comprising a water reservoir arranged in thermal contact with the sole plate (13) and one or more than one discharge opening in fluid communication with the water reservoir via a valve, for densely ejecting steam onto the clothes and a button for operating the valve.