JP2012251376A - In-vehicle equipment control system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-vehicle equipment control system capable of expanding a transmission area of a request signal without requiring an additional in-vehicle transmission antenna and amplifying a transmission output.SOLUTION: An in-vehicle equipment control system comprises: an in-vehicle device having an in-vehicle reception antenna and an in-vehicle transmission antenna 1 which wirelessly transmits a request signal to an interior of a vehicle; and a portable machine which wirelessly transmits an ID signal when receiving the request signal. In the in-vehicle equipment control system, the in-vehicle device enables an in-vehicle equipment to operate when the in-vehicle reception antenna receives the ID signal. The in-vehicle equipment control system also has a conductive loop structure 10 capable of downwardly expanding a transmission area of the request signal. The in-vehicle transmission antenna 1 is installed outside an inner periphery of the conductive loop structure 10. A distance between the in-vehicle transmission antenna 1 and the conductive loop structure 10 is equal to or less than an expandable distance of the transmission area by the conductive loop structure 10.

Description

  The present invention relates to an in-vehicle device control system, and more particularly to an arrangement of an in-vehicle transmission antenna of an in-vehicle device control system.

  In recent years, an in-vehicle device control system in which a portable device plays the role of a conventional mechanical key has been put into practical use. In the in-vehicle device control system, if the driver carries a small portable device such as a card in a pocket or bag, the driver unlocks the door without taking out the portable device, The engine can be started.

  Patent Document 1 below discloses a door lock control system in which an in-vehicle receiving antenna is arranged inside a center cluster that is a position that is less affected by metal vehicle body shielding and has a good visibility.

  Further, in Patent Document 2 below, when the in-vehicle transmission antenna is arranged at a position deviated in the vehicle width direction, the request signal can be transmitted to the doors on both sides by controlling the output intensity of the request signal. A system is disclosed.

JP 2006-132221 A JP 2009-144367 A

  By the way, for example, a small portable device such as a card shape is often sandwiched between sun visors above the driver's seat or placed on the floor under the passenger seat in the back. For this reason, it is necessary to arrange a vehicle-mounted transmission antenna that wirelessly transmits the request signal so that both the position on the sun visor and the floor are the transmission area of the request signal. Examples of such an arrangement position include the vicinity of the instrument panel.

  However, many devices are arranged near the instrument panel. For this reason, it may be difficult to lay out the in-vehicle transmission antenna at an appropriate position inside the instrument panel. In that case, if a vehicle-mounted transmission antenna is arrange | positioned in a lower position, a sun visor will be outside the transmission area of a request signal. On the other hand, if the in-vehicle transmission antenna is arranged at a higher position, the floor is now out of the transmission area.

  Further, if a vehicle-mounted transmission antenna is added or its transmission output is increased, both the sun visor and the floor can be within the transmission area. However, an increase in the number of on-vehicle transmission antennas is not preferable because it increases costs. In addition, an increase in the transmission output of the in-vehicle transmission antenna is not preferable because the transmission area is expanded to the outside of the passenger compartment, and the radio wave of the request signal leaks out of the passenger compartment.

  Therefore, an object of the present invention is to provide an in-vehicle device control system capable of expanding a request signal transmission area without adding an in-vehicle transmission antenna or increasing its transmission output.

  In order to achieve the above object, the inventor according to the present application has conducted various experiments and examinations, and as a result, the in-vehicle transmitting antenna is positioned at a high position where the request signal does not reach the floor in the vehicle cabin with sufficient signal strength. Even in the case where the on-board transmission antenna is placed close to the stay member (center stay) extending upward from the floor panel, the signal intensity of the request signal is increased on the floor. Furthermore, the inventor has also confirmed that when the stay member is separated from the floor panel, the signal strength of the request signal on the floor decreases again.

The present invention has been made on the basis of such knowledge, and an in-vehicle device control system according to the present invention receives an in-vehicle device having an in-vehicle transmission antenna and an in-vehicle reception antenna for wirelessly transmitting a request signal into a vehicle interior, and the request signal. Then, the mobile device includes a portable device that wirelessly transmits an ID signal, and when the vehicle-mounted receiving antenna receives the ID signal, the vehicle-mounted device enables the vehicle-mounted device to operate. A conductive loop structure capable of expanding a transmission area upward and / or downward; and the vehicle-mounted transmission antenna is disposed outside an inner periphery of the conductive loop structure, and the vehicle-mounted transmission antenna and the conductive loop structure The distance is equal to or less than a distance in which the transmission area can be expanded by the conductive loop structure.
The request signal transmission area refers to a range in which the portable device can receive the request signal with sufficient signal strength to stably operate the portable device.

According to the present invention, the transmission area of the request signal is expanded by arranging the in-vehicle transmission antenna near the outside of the loop of the conductive loop structure. This is considered because the conductive loop structure serves as an auxiliary antenna. As a result, the request signal can be delivered with sufficient signal strength even to a place where the request signal with sufficient signal strength has not arrived with the in-vehicle transmission antenna alone. For example, on the sun visor near the ceiling or on the floor in the passenger compartment, when the reception intensity of the request signal is low only with the in-vehicle transmission antenna, the reception area on the sun visor or floor is increased by expanding the transmission area with the conductive loop structure. Can be increased.
Therefore, according to the present invention, the transmission area of the request signal can be expanded without adding an in-vehicle transmission antenna or increasing its transmission output.

  If the in-vehicle transmission antenna is arranged inside the inner periphery of the conductive loop structure (inside the loop), most of the request signal transmitted from the in-vehicle transmission antenna is absorbed by the conductive loop structure. Therefore, the in-vehicle transmission antenna is disposed in a region outside the loop of the conductive loop structure.

  In the present invention, preferably, the conductive loop structure includes a stay member extending upward from a floor panel, a dash panel that is electrically connected to the stay member and forms a partition wall between the engine room and the vehicle compartment, The floor panel is electrically connected to the stay member and the dash panel.

  In this way, by configuring the conductive loop structure with the dash panel, the floor panel, and the stay member, the transmission area of the request signal is effectively expanded downward including the floor in the vehicle interior.

In the present invention, it is preferable that the in-vehicle transmission antenna is disposed outside a portion corresponding to the outer edge of the conductive loop structure of the stay member, and the distance between the in-vehicle transmission antenna and the stay member is a predetermined distance. It is as follows.
Thus, by arranging the in-vehicle transmission antenna outside the outer edge of the conductive loop structure, the request signal transmission area can be effectively expanded.

In the present invention, preferably, the in-vehicle transmission antenna transmits the request signal having a wavelength λ, and a distance between the in-vehicle transmission antenna and the conductive loop structure is 5λ / 100,000 or less.
Assuming that the shortest distance between the in-vehicle transmission antenna and the conductive loop structure is within such a range, the transmission area of the request signal is empirically effectively expanded downward including the floor in the passenger compartment. More preferably, the shortest distance is 4λ / 100000 or less.

Preferably, in the present invention, the in-vehicle transmission antenna includes a loop antenna, and the in-vehicle transmission antenna is disposed so that a loop surface of the loop antenna and a loop surface of the conductive loop structure are parallel to each other. .
Thus, by making the loop surface of the in-vehicle transmission antenna parallel to the loop surface of the conductive loop structure, the transmission area of the request signal can be effectively expanded.

In the present invention, preferably, the in-vehicle transmission antenna is disposed within a range of a semicircular cross-sectional shape centered on the stay member in a plane crossing the stay member.
By arranging the in-vehicle transmission antenna within the range of the semicircular cross-sectional shape, the request signal transmission area can be effectively expanded.

In the present invention, preferably, the semicircular radius is 10 cm.
By arranging the in-vehicle transmission antenna in such a semicircular shape, the transmission area of the request signal can be expanded particularly effectively.

  According to the in-vehicle device control system of the present invention, the transmission area of the request signal can be expanded without adding an in-vehicle transmission antenna or increasing its transmission output.

(A) And (b) is a schematic diagram which shows arrangement | positioning of the vehicle-mounted transmission antenna of a vehicle-mounted apparatus control system, and the transmission area of a request signal. (A) is a schematic diagram which shows the transmission area which can receive the arrangement | positioning and request signal of a vehicle-mounted transmission antenna of the vehicle-mounted apparatus control system by embodiment of this invention directly from a vehicle-mounted transmission antenna, (b) is the expanded transmission. It is a schematic diagram which shows an area. (A) is a side view which shows arrangement | positioning of the conductive loop structure and vehicle-mounted transmission antenna of the vehicle equipment control system by embodiment of this invention, (b) is the top view. It is a side view which shows arrangement | positioning of the conductive loop structure of the vehicle equipment control system by embodiment of this invention, and the vehicle-mounted transmission antenna attached to the stay member.

Hereinafter, an embodiment of an in-vehicle device control system of the present invention will be described with reference to the accompanying drawings.
An in-vehicle device control system according to the present invention includes an in-vehicle device having an in-vehicle transmission antenna and an in-vehicle reception antenna that wirelessly transmits a request signal to a vehicle interior, and a portable device that wirelessly transmits an ID signal (identification signal) when receiving the request signal. It has. When the vehicle-mounted receiving antenna receives the ID signal, the vehicle-mounted device enables operation of the vehicle-mounted device.

  For example, when the driver presses the ignition button of the vehicle, the in-vehicle device causes the in-vehicle transmission antenna to transmit a request signal. The portable device that has received the request signal transmits an ID signal. When the vehicle-mounted receiving antenna receives the ID signal, the vehicle-mounted device permits the vehicle-mounted device to start the engine.

  Here, FIG. 1A shows an arrangement of a conventional vehicle-mounted transmission antenna (LF (long wave) antenna) 1 in a vehicle interior and a transmission area 20 for request signals. In FIG. 1 and FIG. 2, the illustration of the support member of the in-vehicle transmission antenna 1 is omitted.

  In the conventional in-vehicle device control system, the in-vehicle transmission antenna 1 is usually arranged so as to include both the sun visor 2 and the floor in the request signal transmission area 20. However, as shown in FIG. 1B, the in-vehicle transmission antenna 1 is not always laid out at an ideal height, and may be arranged at a higher position. In this case, the sun visor 2 near the ceiling in the vehicle interior is included in the request signal transmission area 20, but the vicinity of the floor in the vehicle interior is outside the request signal transmission area 20.

  In this embodiment, as shown in FIG. 2A, the in-vehicle transmission antenna 1 alone is disposed at a high position such that the vicinity of the floor in the vehicle interior is outside the transmission area 20. However, the in-vehicle transmission antenna 1 is disposed in the vicinity of the outer side of the inner periphery of the conductive loop structure 10 while maintaining its height. The in-vehicle transmission antenna 1 is disposed at a position where the distance between the in-vehicle transmission antenna 1 and the conductive loop structure 10 is equal to or less than the distance at which the transmission area 20 is expanded by the conductive loop structure 10.

  As described above, by arranging the in-vehicle transmission antenna 1 near the outside of the conductive loop structure 10, a part of the energy of the request signal is absorbed by the conductive loop structure 10 and re-radiated. As a result, as shown in FIG. 2B, a new transmission area 30 is formed, and the transmission area of the request signal is extended to the floor. Accordingly, even when the in-vehicle transmission antenna 1 is arranged at a high position, the sun visor 2 arranged near the ceiling in the vehicle interior without increasing the in-vehicle transmission antenna or increasing the transmission output of the request signal. To the floor can be used as a request signal transmission area.

  The conductive loop structure 10 is electrically connected to a stay member (center stay) 13 that extends upward from the floor panel 12 and supports the instrument panel, and a partition wall between the engine room and the vehicle compartment. The dash panel 11 is mainly composed of a floor panel 12 electrically connected to the stay member 13 and the dash panel 11. The dash panel 11, the floor panel 12, and the stay member 13 are all made of metal and have conductivity.

  If the in-vehicle transmission antenna is arranged in the loop of the conductive loop structure 10, most of the energy of the request signal transmitted from the in-vehicle transmission antenna 1 is absorbed by the conductive loop structure 10. As a result, the transmission area where the request signal reaches directly from the in-vehicle transmission antenna is rather narrow. Therefore, the in-vehicle transmission antenna 1 is arranged in a region outside the loop of the conductive loop structure.

  Further, within the predetermined distance is a distance where the shortest distance between the in-vehicle transmission antenna 1 and the stay member 13 is 5λ / 100,000 or less when the wavelength of the request signal transmitted by the in-vehicle transmission antenna 1 is λ. Is good. More preferably, the distance is 4λ / 100000 or less. For example, when the frequency of the request signal is 125 kHz, the wavelength λ is about 2.4 km, and 5λ / 10000 is about 12 cm. In that case, 4λ / 100,000 is about 9.6 cm.

  Further, the conductive loop structure is arranged so that the normal line of the loop surface substantially faces the vehicle width direction. For this reason, the transmission area of the request signal is substantially expanded in the direction along the loop surface of the conductive loop structure by the conductive loop structure. For this reason, even if the transmission area is expanded downward by the conductive loop structure, the transmission area is not substantially expanded in the vehicle width direction. For this reason, the transmission area of the request signal is not expanded outside the door of the vehicle.

  The in-vehicle transmission antenna 1 has a coil antenna that substantially constitutes a plurality of loop antennas. The in-vehicle transmission antenna 1 is arranged such that the loop surface of the loop antenna and the loop surface of the conductive loop structure 10 are substantially parallel. That is, the in-vehicle transmission antenna 1 is arranged so that the axial direction of the coil of the in-vehicle transmission antenna 1 and the normal direction of the loop of the conductive loop structure 10 are substantially parallel. By arranging the in-vehicle transmission antenna 1 in this way, the transmission area can be more effectively expanded by the conductive loop structure 10.

  The conductive loop structure 10 will be described in more detail with reference to FIG. FIG. 3A is a side view of the conductive loop structure, and FIG. 3B is a plan view thereof. In addition to the dash panel 11, the floor panel 12 and the stay member 13, the roundabout loop structure shown in FIG. 3 includes an instrument panel member 14 extending in the vehicle width direction inside the instrument panel, and an instrument panel member 14. It is comprised from the connection member 15 connected to. The stay member 13 is electrically connected to the dash panel 11 via the metal instrument panel member 14 and the connecting member 15.

Then, as shown in FIGS. 3A and 3B, the in-vehicle transmission antenna 1 is disposed outside the portion 13 a corresponding to the outer edge of the conductive loop structure 10 of the stay member 13. The in-vehicle transmission antenna 1 is disposed at a position where the shortest distance between the in-vehicle transmission antenna 1 and the stay member 13 is, for example, about 10 cm or less.
In addition, in FIG. 3A and FIG. 3B, illustration of the member which supports the vehicle-mounted transmission antenna 1 is abbreviate | omitted.

In other words, the placement condition of the in-vehicle transmission antenna 1 is within a range in which at least a part of the in-vehicle transmission antenna 1 has a semicircular cross-sectional shape with a radius of about 10 cm centering on the stay member in a plane crossing the stay member. The in-vehicle transmission antenna 1 is arranged so as to enter. For example, when the stay member 13 is a straight rod-shaped member, the in-vehicle transmission antenna 1 is located outside the conductive loop structure in a columnar region having a radius of about 10 cm centered on a part of the outer edge portion 13a of the stay member 13 ( It is arranged in a columnar region having a semicircular cross section which is the rear side of the stay member 13.
The stay member may have a straight shape, or may have a bent or curved shape.

  Further, as shown in FIG. 4, the in-vehicle transmission antenna 1 may be attached to the stay member 13 via a bracket 16 or directly. The in-vehicle transmission antenna 1 may be arranged so that the antenna extends in the horizontal direction, or may be arranged inclined.

  In the above-mentioned embodiment, although the example which comprised this invention on the specific conditions was demonstrated, this invention can perform a various change and combination, and is not limited to this. In the above-described embodiment, the example of the conductive loop structure in which the normal line of the loop surface substantially extends in the vehicle width direction has been described. However, in the present invention, the direction of the loop surface is not limited to this. For example, you may employ | adopt the conductive loop structure arrange | positioned so that a loop surface may become horizontal.

  Moreover, although embodiment mentioned above demonstrated the example which comprised the conductive loop structure with the metal members, in this invention, the material of the member which comprises a conductive loop structure is not limited to a metal. For example, a conductive plastic material may be used for at least a part of members constituting the conductive loop structure.

In the above-described embodiment, the example in which the transmission area of the request signal is expanded downward has been described. However, in the present invention, the transmission area may be expanded upward. In that case, for example, the conductive loop structure may be provided so as to extend above the position of the portable device.
Further, the shape of the portable device is not limited to the card shape, and can be any suitable shape.

1 In-vehicle transmission antenna (LF antenna)
10 Conductive Loop Structure 11 Dash Panel 12 Floor Panel 13 Stay Member (Center Stay)
14 Instrument panel members 15 Connecting members 20 Transmission area 30 New transmission area

Claims (7)

A vehicle-mounted device having a vehicle-mounted transmitting antenna and a vehicle-mounted receiving antenna for wirelessly transmitting a request signal into the vehicle interior;
A portable device that wirelessly transmits an ID signal when receiving the request signal;
When the vehicle-mounted receiving antenna receives the ID signal, the vehicle-mounted device is a vehicle-mounted device control system that enables operation of the vehicle-mounted device,
Comprising a conductive loop structure capable of expanding the transmission area of the request signal to at least one of an upper side and a lower side;
The vehicle-mounted transmitting antenna is disposed outside the inner periphery of the conductive loop structure,
A vehicle-mounted device control system, wherein a distance between the vehicle-mounted transmission antenna and the conductive loop structure is equal to or less than a distance by which the transmission area can be expanded by the conductive loop structure. The conductive loop structure is
Stay members extending upward from the floor panel;
A dash panel that is electrically connected to the stay member and forms a partition wall between the engine room and the vehicle compartment;
The floor panel in electrical communication with the stay member and the dash panel;
The vehicle-mounted device control system according to claim 1, characterized by comprising: The in-vehicle transmission antenna is disposed outside a portion corresponding to the outer edge of the conductive loop structure of the stay member,
The in-vehicle device control system according to claim 1 or 2, wherein a distance between the in-vehicle transmission antenna and the stay member is a predetermined distance or less. The in-vehicle transmission antenna transmits the request signal having the wavelength λ,
The in-vehicle device control system according to any one of claims 1 to 3, wherein a distance between the in-vehicle transmission antenna and the conductive loop structure is 5λ / 100000 or less. The in-vehicle transmission antenna has a loop antenna,
5. The on-vehicle transmission antenna is arranged such that a loop surface of the loop-shaped antenna and a loop surface of the conductive loop structure are parallel to each other. 6. In-vehicle device control system. 6. The vehicle-mounted transmitting antenna is disposed within a range of a semicircular cross-sectional shape centering on the stay member in a plane crossing the stay member. The in-vehicle device control system described in 1. The in-vehicle device control system according to claim 6, wherein the semicircular radius is 10 cm.

Images