JP2020167553A - Antenna device - Google Patents

Abstract

To provide an antenna device capable of managing tools and the like with a simple configuration and good workability, for example.SOLUTION: The antenna device has a plurality of sleeve antennas 11 to 14 connected in parallel and bundled into one, and disposes an antenna unit 15 of each of the sleeve antennas 11 to 14 to be shifted in a longitudinal direction by λ/2 or more when a wavelength of an electric wave is denoted as λ. The bundled sleeve antennas 11 to 14 are disposed to surround a read area 24 in which a plurality of identifiers storing preset individual information is disposable. It is preferable that electric waves are transmitted and received between the antenna unit 15 and the identifiers.SELECTED DRAWING: Figure 1

Description

The present invention relates to, for example, an antenna device suitable for use such as tools and tool management.

For example, in construction and maintenance work, a wide variety of tools and tools (hereinafter referred to as tools, etc.) are used at one time. At this time, if the used tools or the like are lost (misplaced), there is a high risk of having a great influence (adverse effect) on the factory equipment and safety.
Therefore, as a breakthrough measure that relies on management left to the operator, an identifier such as an RF tag or barcode (QR code (registered trademark)) is attached to a tool or the like, and this identifier is attached to, for example, a portable terminal ( A method of managing tools and the like by checking with a handy terminal or the like has been considered.
However, in the case of RF-ID, since the antenna used for the terminal has directivity (range in which radio waves can be transmitted and received), the identifier may not be read by the above method.
Therefore, for example, the RFID tag reading system and the RFID tag reading method described in Patent Document 1 have been proposed. Specifically, it includes a reading device that reads data from an RFID tag (RF tag) and an antenna system that transmits and receives electromagnetic waves.

Japanese Unexamined Patent Publication No. 2008-123231

However, in the technique described in Patent Document 1 described above, the antenna system includes the first to third antennas, and the radiation direction of the second antenna is the radiation direction of the first antenna connected to the reading device. Since the antenna is arranged so as to face the antenna and the third antenna is connected to the second antenna, the device configuration is complicated.
In addition, there are roughly two types of usage patterns for tools and the like.
1) Frequently used tools, etc. are stored in the tool belt by the operator and always carried.
2) When the type and size of tools change frequently, or when the size of tools is relatively large, the tools are stored in a tool box (container) and carried together.
The storage management of tools may be performed on shelves or warehouses.
All of the tools used in this way can be used anytime, anywhere (for example, before departure to the work site, at the end of work at the work site, before withdrawal from the work site) without increasing the burden on the operator. It has been desired to prevent the loss of tools, etc. by surely performing individual authentication, checking the presence or absence of tools, etc., and leaving the history of the check (verification) results on the system.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide an antenna device capable of managing tools and the like with a simple configuration and good workability.

The antenna device according to the present invention according to the above object has a plurality of sleeve antennas connected in parallel and bundled into one, and the antenna portion of each sleeve antenna has a wavelength of radio waves in the longitudinal direction thereof. They are arranged with a shift of λ / 2 or more as λ.

In the antenna device according to the present invention, the bundled sleeve antenna is arranged so as to surround a reading area in which a plurality of identifiers storing preset individual information can be arranged, and is located between the antenna unit and the identifier. It is preferable that radio waves are transmitted and received at.

In the antenna device according to the present invention, each of the sleeve antennas is attached and fixed around a container or a shelf in which a plurality of articles including one or both of tools and tools are housed, and the identifier is attached to each of the articles. It is preferable to be fixed.

In the antenna device according to the present invention, an RF tag that transmits a response wave including the individual information by radio waves when a question wave is received by radio waves can be used as the identifier.

In the antenna device according to the present invention, since a plurality of sleeve antennas connected in parallel are bundled into one, the device configuration can be simplified and the manufacturing cost can be reduced, and a plurality of sleeve antennas are used. The workability associated with this can also be improved.
Further, since the antenna portions of the sleeve antennas are arranged so as to be displaced by λ / 2 or more in the longitudinal direction thereof, the antenna portions of the sleeve antennas are not arranged next to each other. As a result, each antenna unit can transmit and receive radio waves to and from an identifier attached and fixed to, for example, a tool, etc., so even if each sleeve antenna has directivity, either one (all). It is possible to send and receive radio waves with the sleeve antenna.
Therefore, for example, the management of tools and the like can be carried out with a simple configuration and with good workability (recognition errors of the tools and the like can be reduced as compared with the conventional case).

(A) is an explanatory view of an antenna device according to an embodiment of the present invention, and (B) is a cross-sectional view taken along the line aa of (A). It is explanatory drawing of the sleeve antenna which comprises the antenna device. (A) is an explanatory diagram of a usage example of the antenna device, and (B) is an explanatory diagram of a state in which (A) is viewed in a plan view.

Subsequently, an embodiment embodying the present invention will be described with reference to the attached drawings, and the present invention will be understood.
As shown in FIGS. 1A, 1B, and 2A, a plurality of antenna devices 10 according to an embodiment of the present invention are connected in parallel and bundled into one (here, four). ), And the antenna portions 15 of the sleeve antennas 11 to 14 are arranged so as to be offset in the longitudinal direction thereof. Each antenna portion 15 is, for example, a plurality of RF tags described later. It sends and receives radio waves to and from (an example of an antenna). The details will be described below.

The sleeve antenna 11 (the same applies to the other sleeve antennas 12 to 14) has the same configuration as the existing sleeve antenna. Specifically, as shown in FIG. 2, an antenna portion (a core wire conductor) 18 covered with an insulator (insulating member) 17 is formed from the front end portion of the coaxial cable (coaxial feeding line) 16. The radiation portion) 15 is formed, and the net-like outer conductor (net wire) 19 of the coaxial cable 16 covering the antenna portion 15 is folded back toward the base side of the coaxial cable 16 to form the outermost layer portion of the coaxial cable 16. The sleeve 21 is formed by covering the outer cover (insulating member) 20 to be used. The sleeve may also be configured by covering the outer circumference of the outer conductor 19 with a coaxial circular tube.

Both the length of the antenna portion 15 and the length of the sleeve 21 are generally set to λ / 4, where λ is the wavelength of the radio wave to be received, but other lengths can be used.
The antenna unit 15 transmits and receives radio waves to and from the RF tag, and when the frequency of the radio waves is 920 MHz, the wavelength λ is 326.0 mm (λ / 4 is 81.5 mm), but the frequency is The length is not limited to this, and may be, for example, 2.4 GHz, and the lengths of the antenna portion and the sleeve are also changed according to this frequency.

As shown in FIGS. 1A and 1B, the plurality of sleeve antennas 11 to 14 are bundled (integrated) into one. As a method of bundling a plurality of sleeve antennas 11 to 14 into one, for example, a binding band (band material) or the like can be used, but the entire bundled sleeve antennas 11 to 14 are covered with a resin covering material. It can also be covered, which prevents dirt from adhering to the antenna portion 15.
In this way, when bundling a plurality of sleeve antennas 11 to 14 into one, it is easy to carry (lightweight) by reducing the maximum outer diameter of the sleeve antenna (outer diameter: for example, 10 mm or less, preferably 5 mm or less). It is preferable from the viewpoint of operability (flexibility) and operability.

The antenna portions 15 of the sleeve antennas 11 to 14 described above are arranged in the longitudinal direction of the antenna device 10 with the wavelength of the radio wave as λ and shifted by λ / 2 or more. Specifically, the antenna portion 15 and the sleeve 21 of the sleeve antenna 11 are arranged (adjacently arranged) adjacent to the outer cover 20 which is an insulating member of the coaxial cable 16 of the other sleeve antennas 12 to 14 (others). The sleeve antennas 12 and 13 of the above are substantially the same, but the antenna portion 15 of the sleeve antenna 14 is arranged independently).
As a result, even if there is a coaxial cable 16 next to the antenna portion 15, the mutual influence of the respective antennas can be reduced, and the performance as an antenna can be exhibited.

The distance S between the antenna portions 15 and the sleeves 21 adjacent to each other in the longitudinal direction of the antenna device 10 is such that, for example, the antenna portions 15 and the sleeve 21 of the sleeve antenna 11 are adjacent to the outer cover 20 of the sleeve antennas 12 to 14. The arrangement is not particularly limited as long as the antenna portion 15 is arranged (shifted by λ / 2 or more), but may be, for example, 5 cm or more (each interval S may be the same or different).
On the other hand, the upper limit value of the interval S is set in consideration of, for example, the range in which radio waves can be transmitted and received from the RF tag and the directivity of the sleeve antenna.

The base ends of the sleeve antennas 11 to 14 (coaxial cable 16) described above are individually connected (connected in parallel) to one distributor 22, and the distributor 22 is read by a single coaxial cable (not shown). ) (See FIG. 3 (A)).
The distributor 22 evenly distributes a predetermined high-frequency current sent from the reading means to the sleeve antennas 11 to 14, and has the same configuration as the existing distributor.
The reading means has the same configuration as the existing RF tag reader (reader / writer), and may or may not supply power to the RF tag.

This reading means transmits a high-frequency current from a reader / writer to each sleeve antenna 11 to 14 by using an RF-ID mechanism, and transmits it as an electromagnetic wave. When the RF tag receives the electromagnetic waves transmitted from the sleeve antennas 11 to 14, preset data (an example of individual information) is returned as electromagnetic waves. The returned electromagnetic wave is read by the sleeve antennas 11 to 14.
A computer is connected to the reading means by wire or wirelessly, and the above operation can be automatically repeated at a predetermined cycle based on a preset program. The contents of the data read by the reading means, the operating status of the reading means, and the like are transmitted and stored in this computer.

The RF tag is an identifier that stores data.
Examples of this RF tag include an electronic tag, an IC tag, an ID tag, a transponder, a wireless tag, a wireless IC tag, and the like.
The RF tag is a passive type that operates only with the power supplied from the reading means (mounted battery: none), but a semi-passive type that operates by communicating with the power supplied from the reading means (mounted battery: yes (only for the sensor)). ) Or an active type (on-board battery: Yes (for communication and sensor)) that operates entirely with the power supplied from the built-in (mounted) battery.

Subsequently, an example of managing tools and tools by using the antenna device 10 described above will be described with reference to FIGS. 3 (A) and 3 (B).
Each sleeve antenna 11-14 is attached and fixed around a container 23 in which a plurality of articles (not shown) are housed. Specifically, the sleeve antennas 11 to 14 are attached and fixed to the outer side surfaces of the side walls of the rectangular parallelepiped container 23 having an open upper portion.
The shape of the container is not particularly limited, and for example, a cube having an open upper portion can be used depending on the application (for example, the type of the article to be stored).

As a result, the bundled sleeve antennas 11 to 14 (that is, the antenna device 10) are arranged so as to surround the inside of the container 23, so that the inside of the container 23 becomes the reading area 24 by each sleeve antenna 11 to 14. ..
The sleeve antennas 11 to 14 are attached to the container 23 so that the transmission / reception range of each radio wave partially overlaps (partially overlaps) (so that the entire reading area 24 can be covered). There is. Therefore, if this condition is satisfied, it can be attached and fixed to another position (for example, the outer or inner surface of the bottom of the container, or the partition plate of the article arranged inside the container), and this attachment position is described above. It can also be used in combination with the mounting position.

The attachment target of each of the sleeve antennas 11 to 14 is not limited to the container 23, and may be, for example, a shelf for accommodating a plurality of articles or a belt (worker's body) wrapped around the body by the worker. .. The plurality of articles consist of one or both of the tool and the tool (that is, the plurality of articles consist of the tool only, the tool only, or both the tool and the tool), but are limited thereto. It's not a thing.
RF tags are attached and fixed to each article. The RF tag is preferably attached to the article by sticking, but is not limited to this, and may be wound or hung, for example, depending on the type of article (use environment). ..

The orientations of a plurality of articles, for example, a plurality of tools, are irregular (not aligned) because they are usually of different sizes and are randomly housed in a container (tool box).
Therefore, in order to read the RF tag attached to the tool housed in the container, the antenna must be omnidirectional (the RF tag side may be directional), and the antenna configuration is simple. It needs to have a high degree of freedom and be inexpensive.
Therefore, a plurality of sleeve antennas 11 to 14 are used as the antennas constituting the antenna device 10 of the present invention.

Subsequently, a tool and a tool management method using the antenna device 10 will be described.
After the worker performs the construction and maintenance work, the used tool (an example of an article) is stored in the container 23.
Sleeve antennas 11 to 14 are attached and fixed to the container 23. Further, RF tags are attached to each of the plurality of tools housed in the container 23. This RF tag is a passive type and operates only with the power supplied from the reading means, but may be a semi-passive type, an active type, or the various RF tags described above.

Next, when the reading means is operated by a computer to perform the reading operation, the reading means sends a predetermined high-frequency current to the sleeve antennas 11 to 14 via the distributor 22. When this high-frequency current is supplied to the sleeve antennas 11 to 14, radio waves are radiated from each antenna unit 15 (all sleeve antennas 11 to 14 simultaneously perform the radio waves). This radio wave is a question wave that operates the RF tag.
As a result, when the strength of the electromagnetic field in the container 23 (reading area 24) becomes equal to or higher than a predetermined value, the RF tag in the container 23 can be operated.

When the question wave radiated from the antenna unit 15 is received by the RF tag located in the container 23, the radio wave (answer wave) transmitted from this RF tag is received by the antenna unit 15, and the high frequency representing this answer wave is received. The current is input to the reading means.
The reading means demodulates this high frequency current and reads the data of the RF tag.
The above operation is performed based on a program preset in the computer, and the obtained data is sent to the computer and saved.
As a result, the presence or absence of the tool can be checked, and the history of the check (verification) result can be left on the system, so that the loss of the tool can be prevented.

Although the present invention has been described above with reference to the embodiments, the present invention is not limited to the configuration described in the above-described embodiments, and the matters described in the claims. It also includes other embodiments and variations that may be considered within the scope. For example, the case where the antenna device of the present invention is configured by combining a part or all of the above-described embodiments and modifications is also included in the scope of rights of the present invention.
In the above embodiment, the case where the number of sleeve antennas to be bundled into one is four has been described, but a plurality of sleeve antennas may be used, for example, two, three, or five or more. it can. The upper limit value is not particularly limited, but is, for example, about 20 antenna devices (preferably 15 antenna devices, more preferably 10 antenna antennas) in consideration of portability and operability of the antenna device. In this way, when the number of sleeve antennas is increased, the current sent to each sleeve antenna is distributed by the distributor and becomes smaller. Therefore, for example, about 2 to 5 antennas are grouped in parallel in one distributor. It is good to connect.

Further, in the above-described embodiment, the axial centers of the antenna portions of the plurality of sleeve antennas are arranged so as to be aligned with the longitudinal direction of the antenna device, but the present invention is not limited to this. For example, among a plurality of sleeve antennas, the axis of the antenna portion (which may include a sleeve) of a part or all of the sleeve antennas intersects the longitudinal direction of the antenna device (the same direction or different directions). It can be arranged according to (good), or the antenna portion can be arranged in an L shape or bent at an acute angle or an obtuse angle.
By adjusting the arrangement direction of the antenna unit and changing the shape of the antenna unit in this way, the radio wave transmission / reception range of each antenna unit can be overlapped in the optimum state, and the recognition error of the identifier can be further increased. Can be reduced.

10: Antenna device, 11-14: Sleeve antenna, 15: Antenna part, 16: Coaxial cable, 17: Insulator, 18: Center conductor, 19: External conductor, 20: Cover, 21: Sleeve, 22: Distributor , 23: Container, 24: Reading area

Claims (4)

It has a plurality of sleeve antennas connected in parallel and bundled into one, and the antenna portions of the sleeve antennas are arranged in the longitudinal direction with a wavelength of radio waves of λ and a shift of λ / 2 or more. A featured antenna device. In the antenna device according to claim 1, the bundled sleeve antenna is arranged so as to surround a reading area in which a plurality of identifiers storing preset individual information can be arranged, and the antenna portion and the identifier are arranged. An antenna device characterized in that radio waves are transmitted and received between them. In the antenna device according to claim 2, each of the sleeve antennas is attached and fixed around a container or a shelf in which a plurality of articles including one or both of tools and tools are housed, and the identifier is attached to each of the articles. An antenna device that is mounted and fixed. The antenna device according to claim 2 or 3, wherein the identifier is an RF tag that transmits a response wave including the individual information by radio waves when a question wave is received by radio waves.

Images