WO2017005542A1

WO2017005542A1 - A communication means and the household appliance wherein the same is used

Info

Publication number: WO2017005542A1
Application number: PCT/EP2016/064964
Authority: WO
Inventors: Sezgi YIKILMAZCINAR; Selami SEVIK; Oner Hatipoglu
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2015-07-08
Filing date: 2016-06-28
Publication date: 2017-01-12
Anticipated expiration: 2018-01-08

Abstract

The present invention relates to a communication means (1 ) that provides the household appliance wherein the communication means (1 ) is used with wireless transmission feature and that comprises a feeding unit, a lower layer (2) which is a printed circuit board, an antenna (3) that is disposed on the lower layer (2) and that has a ground connection (4) and a feed point (5).

Description

A COMMUNICATION MEANS AND THE HOUSEHOLD APPLIANCE WHEREIN THE SAME IS USED

The present invention relates to a communication means that provides communication between the household appliances and between the household appliances and the user, to a household appliance wherein the said communication means is used.

According the radio frequency arrangements, frequencies that can be used for wireless communication without obtaining licenses are determined. Frequencies that the household appliances can use are defined as ISM (Industrial, scientific and medical) band. In this band, different frequencies are determined for different regions and since using an appliance specific to a certain region in another region causes interference, it poses a problem. Therefore, the producers who do not want to produce different appliances for different regions are forced to use broadband communication means, in particular broadband antenna. In the technique, the communication means are used externally or as integrated. In the integrated communication means, the use of a low-cost communication means that is composed of an antenna printed on a printed circuit board is known. However, the dipole antennas working in frequencies defined by standards, for example in frequencies in the vicinity of 800-900 MHz have a length of about 15cm and the monopole antennas have a length of about 8cm; moreover, producing broadband antennas in the said low frequencies is more difficult in comparison to higher frequencies, for example 2.4 GHz. These large dimensions affect the design of the household appliances and cause the communication means to occupy a large space on the household appliances. Helical antennas that can be produced in smaller sizes are sensitive to production tolerances and not suitable for mass production. In addition, the helical antennas have antenna gain. However, the communication means used in the household appliances are required to be non-directional and to be capable of broadcasting and receiving broadcast omni-directionally. Therefore, low gain antennas are preferred.

In the state of the art European Patent Application No. EP2851997, a printed circuit board antenna is disclosed, comprising a coupling circuit so as to work in different wavelengths.

In the state of the art European Patent Application No.EP2763238, a printed circuit board antenna that can work in different bandwidths is disclosed.

In the state of the art European Patent Application No. EP1095422, a communication means is disclosed, comprising an integrated antenna that can work in different wavelengths.

The aim of the present invention is the realization of a small-sized and low-cost communication means and a household appliance wherein the said communication means is used.

The communication means realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises an antenna having a plurality of branches that are asymmetrically positioned on a linear section extending from a feed point for a certain length.

The antenna part of the communication means comprises ten branches that are perpendicularly positioned on the linear section. The branches are arranged as two groups of two and two groups of three starting from the closest one to the feed point. In the two groups of two, the branch closer to the feed point is shorter than the other. In the two groups of three, the branches are arranged so as to be medium - long - short length according to their proximity to the feed point. The branches have a length that is one twentieth or one fifteenth of the resonance wavelength. Moreover, the branches are positioned in an eccentric manner on the linear section. A printed circuit board is used as the lower layer wherein the antenna pattern is situated and the said printed circuit board is produced in the standard thickness and from standard materials.

In order to provide impedance matching in the communication means, a gap is provided on the ground connection and the feed point of the antenna is printed on the printed circuit board so as to be in the gap. The linear section extending from the feed point is selected in a length that is between one fifth and one sixth of the resonance wavelength.

With the above-mentioned features thereof, the communication means have a broad bandwidth around the desired central frequency. Thus, the household appliance wherein the communication is used can be used in different regions without requiring any extra component. The broad bandwidth also enables the household appliance to wirelessly transfer audio and video.

The said communication means has a simpler design than the state of the art means and is produced with lower costs. Moreover, the above-mentioned antenna pattern is resistant to production tolerances and is minimally affected by production errors. Thus, losses that may occur during mass production can be minimized, thus providing cost advantage.

By means of the above-mentioned antenna pattern, a small-sized communication means is realized in the license-free frequency band reserved for industrial use in radio frequency arrangements and the communication means can be easily integrated to the edge of the printed circuit board that constitutes the control card of the household appliance wherein the communication means is used.

The household appliance wherein the communication means of the present invention is used is in particular a cooking device, an exhaust hood system with an image processing means. By means of the image processing means, the exhaust hood can reflect the information received from the cooking device onto the kitchen counter and thus the user is not required to bend over to see the status of the cooking device. The household appliance wherein the communication means of the present invention is used is not limited to the above-mentioned sample household appliances, and can be a cooling device, a laundry washer and/or dryer, a dishwasher or a small home appliance.

The communication means realized in order to attain the aim of the present invention is illustrated in the attached figures, where:

Figure 1 – is the schematic view of a communication means.

Figure 2 – is the graphic of the losses by frequency of the communication means related to an embodiment of the present invention.

Figure 3 – is the graphic of gain in 868 MHz frequency of the communication means related to an embodiment of the present invention.

Figure 4 – is the graphic of gain in 915 MHz frequency of the communication means related to an embodiment of the present invention.

The elements illustrated in the figures are numbered as follows:

1. Communication means

2. Lower layer

3. Antenna

4. Ground connection

5. Feed point

6. Linear section

7. Branch

8. Gap

The following symbols are used for explicating the communication means (1) of the present invention:

d1 : Length of the first branch

d2 : Length of the second branch

d3 : Length of the third branch

d4 : Length of the fourth branch

d5 : Length of the fifth branch

d6 : Length of the sixth branch

d7 : Length of the seventh branch

d8 : Length of the eighth branch

d9 : Length of the ninth branch

d10 : Length of the tenth branch

da : Distance between the second branch and the third branch

db : Distance between the fourth branch and the fifth branch

dc : Distance between the seventh branch and the eighth branch

The communication means (1) comprises a feeding unit (not shown in the figures), a lower layer (2) and an antenna (3) that is disposed on the lower layer (2) and that has a ground connection (4) and a feed point (5).

The communication means (1) of the present invention comprises the antenna (3) having

- a linear section (6) that extends from the feed point (5) in a certain length and

- a plurality of branches (7) in different lengths that are disposed on the linear section (6) and that are asymmetrically arranged on the linear section (6) so as to be perpendicular to the linear section (6) (Figure 1).

The communication means (1) is driven in the resonance frequency over the feed point (5) by the feeding unit. Moreover, the feeding unit receives signals in the resonance frequency that are captured by the antenna (3). In other words, the communication means (1) works as a receiver and/or transmitter. The person skilled in the art can easily change the gain, efficiency, resonance frequency and bandwidth of the communication means (1) by changing the positions of the branches (7) on the linear section (6).

By means of the antenna (3) pattern of the present invention, a communication means (1) with an 11% bandwidth in 900 MHz frequency is realized (Figure 2). Figure 2 shows the backscatter ratio by frequency of the signal transmitted from the antenna (3), in technical terms the S parameter. In this graphic, for an antenna (3) of a certain size, values lower than 0.3 show an antenna (3) efficiency of 90%. The communication means (1) with the said bandwidth is explained hereinafter in detail.

In Figure 3 and Figure 4, for an antenna (3) driven in two frequencies, the gain graphic of the antenna (3) is shown in two directions, in other words in the azimuth plane. Therefore, when driven in a frequency of 868 MHz, the antenna (3) of the present invention has a 1.79 dB gain with an azimuth plane of 4 degrees (Figure 3). When driven in a frequency of 915 MHz, the antenna (3) has a 1.85 gain with an azimuth plane of 3 degrees. As shown in Figure 3 and Figure 4, the antenna (3) of the present invention has a gain over 1.7 dB in almost all directions and the antenna (3) is considered non-directional according to standards.

The antenna (3) of the communication means (1) comprises ten branches (7) that are perpendicularly positioned on the linear section (6) (Figure 1).

In the communication means (1), the branches (7) are arranged so as to in two groups of two and two groups of three. The distances between the branches (7) can be equal or can be different (Figure 1).

In the branches (7) groups having two branches (7), the branch (7) away from the feed point (5) is longer than the branch (7) close to the feed point (5). As shown in Figure 1, the second branch (7) is longer than the first branch (7) and the fourth branch (7) longer than the third branch (7) (d2 > d1 and d4 > d3). In this embodiment, the branch (7) closest to the feed point (5) is referred to as the first branch (7) so as to more easily describe the invention and in fact, there are no structural differences between the branches (7) required for the operation of the invention.

The branches (7) positioned as groups of three are arranged so as to be medium - long - short length as the distance to the feed point (5) increases. As shown in Figure 1, the fifth branch (7) is shorter than the sixth branch (7) and longer than the seventh branch (7) (d6 > d5 > d7) while the eighth branch (7) is shorter than the ninth branch (7) and longer than the tenth branch (7) (d9 > d8 > d10).

The distance between the branch (7) groups increases towards the end of the linear section (6) starting from the feed point (5). As shown in Figure 1, the distance between the fourth branch (7) and the fifth branch (7) is longer than the distance between the second branch (7) and the third branch (7) and shorter than the distance between the seventh branch (7) and the eighth branch (7) (da < db < dc).

The branches (7) disposed on the linear section (6) have a length that is between one twentieth and one fifteenth of the resonance wavelength. A communication means (1) with the above-described antenna (3) pattern has a low gain, in other words is non-directional, in other words omni-directionally sends signals in almost equal power.

The branches (7) are eccentrically arranged on the linear section (6). With the arrangement pattern of the branches (7) positioned on the linear section (6), a broad bandwidth in the above-mentioned frequencies is obtained. However, the person skilled in the art can obtain broader bandwidths by easily changing, in particular increasing the area and the thickness of the branches (7).

The lower layer (2) used in the communication means (1) is a printed circuit board. The lower layer (2) is in particular a printed circuit board with a thickness of 1.6mm and produced from FR4 material. Thus, the communication means (1) is produced as integrated with the control unit on the household appliance and the production costs are substantially decreased. Moreover, as can be easily seen by the person skilled in the art, by positioning the antenna (3) pattern at the edge of the printed circuit board, a broader bandwidth and a higher efficiency are obtained.

A gap (8) is arranged on the ground connection (4) provided on the printed circuit board and the feed point (5) is positioned in the said gap (8). Thus, the impedance of the antenna (3) is improved so that the impedance of the communication means (1) of the present invention is about 50Ω at the feed point (5). By obtaining an impedance of 50Ω at the feed point (5), the standard impedance level in the technique is obtained and the communication means (1) can be used with the state of the art feeding units without requiring any impedance tuners.

The length of the linear section (6) of the antenna (3) is of a length that is between one fifth and one sixth of the resonance wavelength. Thus, a communication means (1) is realized, that is smaller than the communication means (1) with the state of the art monopole and dipole antennas (3).

In the above-described communication means (1), the lengths and distances given for the antenna (3) have a production tolerance of +-10%.

In the antenna (3), in order to control the bandwidth and the input impedance, the ground connection (4) is also printed on at least on other layer of the printed circuit board. In summary, the ground connection (4) shown in Figure 1 is present in at least two layers of the printed circuit board. As can be easily understood by the person skilled in the art, the ground connection (4) and the antenna (3) pattern are obtained by printing copper on the printed circuit board.

In the household appliance of the present invention, the above-described communication means (1) is used for wireless transmission. The household appliance can be an oven, a cooker, a dishwasher, an exhaust hood, a laundry washer or a refrigerator used in the user's kitchen or bathroom and requiring image and signal transmission to communicate with other household appliances and the user. For example, by means of the communication means (1) used in a refrigerator, the images of the refrigerator shelves are displayed for the user or the exhaust hood can capture the images of the foods that are being cooked on the cooker by means of the camera and the processor thereon so as to analyze the same and to send control commands to the cooker.

Claims

A communication means (1) comprising a feeding unit, a lower layer (2) and an antenna (3) that is disposed on the lower layer (2) and that has a ground connection (4) and a feed point (5), characterized by the antenna (3) having

- a linear section (6) that extends from the feed point (5) in a certain length and

- a plurality of branches (7) in different lengths that are disposed on the linear section (6) and that are asymmetrically arranged on the linear section (6) so as to be perpendicular to the linear section (6).
A communication means (1) as in Claim 1, characterized by ten branches (7) that are disposed on the linear section (6).
A communication means (1) as in Claim 2, characterized by the branches (7) that are arranged in two groups of two and two groups of three.
A communication means (1) as in Claim 3, characterized by the branch (7) that is longer than the branch (7) closer to the feed point (5) in the groups with two branches (7).
A communication means (1) as in Claim 3, characterized by the branches (7) that are arranged so as to be medium - long - short length as the distance to the feed point (5) increases in the groups with three branches (7).
A communication means (1) as in Claim 3 to 5, characterized by the branches (7) wherein the distance between the groups increases starting from the feed point (5) towards the end of the linear section (6).
A communication means (1) as in any one of the above claims, characterized by the branches (7) whereof the lengths are between one twentieth and one fifteenth of the resonance wavelength.
A communication means (1) as in any one of the above claims, characterized by the branches (7) that are eccentrically arranged on the linear section (6).
A communication means (1) as in any one of the above claims, characterized by the lower layer (2) which is a printed circuit board.
A communication means (1) as in Claim 9, characterized by the lower layer (2) whereof the thickness is 1.6mm.
A communication means (1) as in Claim 9 or 10, characterized by the lower layer (2) that is produced from FR4 material.
A communication means (1) as in any one of the above claims, characterized by a gap (8) arranged on the ground connection (4) and the feed point (5) positioned so as to be in the gap (8).
A communication means (1) as in any one of the above claims, characterized by the antenna (3) whereof the impedance at the feed point (5) is 50Ω.
A communication means (1) as in any one of the above claims, characterized by the linear section (6) whereof the length is between one fifth and one sixth of the resonance wavelength.
A household appliance wherein the communication means (1) disclosed in the above claims is used.