Patent Application
20080247184
This application claims the priority benefit under 35 U.S.C. ยง119 of Japanese Patent Application No. 2007-091245 filed on Mar. 30, 2007, which is hereby incorporated in its entirety by reference.
1. Field
The presently disclosed subject matter relates to a keyless entry system having a construction in which a vehicle door can be unlocked by pushing, for example, a button of a device like a TV remote controller when the operator (e.g., driver of the vehicle concerned) approaches the vehicle at a suitable distance. The unlocking operation can be accomplished without inserting a key into a keyhole of the vehicle door to effect unlocking. More particularly, the disclosed subject matter is concerned with a keyless entry system of the type which uses infrared light for communication with a vehicle with respect to opening or closing of doors, for example.
2. Description of the Related Art
Japanese Patent Laid-Open Publication No. 2006-144432 discloses a conventional keyless entry system.
The vehicle 80 includes a processor 81 and a buzzer driver 82. First, the radio wave transmitted from the electronic key 91 is analyzed to check whether the radio wave orders unlocking (or locking) for this vehicle. In the case of an unlocking (or locking) order, unlocking (or locking) is performed by the processor 81.
At the same time the processor 81 turns ON the buzzer driver 82. First, an ambient noise is measured by a microphone 83 and a buzzer 84 is allowed to sound at an appropriate sound volume on the basis of the sound volume of the ambient noise, announcing to the driver and other persons and/or entities that unlocking (or locking) of this vehicle was performed. However, in the above described conventional keyless entry system 90, first, since a radio wave is used for both locking and unlocking, the transmitter that is used is of about the size of a key holder at most and cannot emit many kinds of coded radio waves. Such a transmitter usually emits, for example, one kind of a coded radio wave.
Therefore, for example when the driver exits the vehicle, all four doors of the vehicle are unlocked if the vehicle is a four-door vehicle. As the case may be, a door is apt to be left unlocked when parking, thus giving rise to the problem that the vehicle is more likely to suffer from damage due to theft, vandalism, etc.
When locking or unlocking is performed, the buzzer 84 is sounded to inform the operator that the said operation was performed. Generally, however, ambient noise differs greatly between daytime and nighttime operation. Therefore, to prevent the buzzer from sounding at an excessively large volume, an ambient noise is measured by the microphone 83 and the buzzer is sounded at an appropriate sound volume on the basis of the measurement result, as noted above. However, there are certain problems associated with sound characteristics. For example, there exists a problem of variable sound volume and a problem of variable sound quality. No matter how low the sound volume and how good the sound quality may be, there inevitably exist people who do not prefer the particular sound characteristics. This point has also been regarded as a problem.
According to the present disclosed subject matter, the above-mentioned and other characteristics, problems, and features of the conventional art are taken into consideration when providing a keyless entry system for locking and unlocking at least a certain lock of a vehicle. The keyless entry system can include an infrared light projector having a narrow radiation angle and a light receiving/emitting unit corresponding to operating conditions of certain locks or keys. The light receiving/emitting unit can include at least one set of structures that have a combination of a light receiving element for receiving the infrared light and a light emitting element for indicating the position of a lock which has come into operation correspondingly to the infrared light received by the light receiving element. With this keyless entry system, all of the doors can be prevented from being inappropriately unlocked or locked at the same time. In addition, a sound for confirming the operation that is or has been performed is not generated. Thus, the foregoing described conventional problems can be solved or prevented.
Because infrared light is used for the unlocking command, lapping and transmission as occurs in the conventional use of radio wave energies/frequencies can be avoided. In addition, only a door that is requested to be unlocked by a vehicle occupant, e.g., only the driver's seat-side door can be specifically unlocked. Consequently, certain problems associated with the conventional keyless entry system, which may lead leaving a door unlocked due to all the doors being unlocked at the same time, can be prevented.
Moreover, since locking and unlocking are announced by using a light, a sound is not generated even during parking at night. For example, even when going home late at night, it is possible to prevent disturbing the neighbors due to a sound emitted from the keyless entry system.
The presently disclosed subject matter will now be described in detail by way of embodiments thereof illustrated in the drawings.
The light receiving/emitting unit 2 is usually attached to an outer ceiling/roof of the vehicle in a state in which the four unit sections 3 (a-d in the case of a four-door vehicle) face upward and a processing circuit 10 is embedded for example within the vehicle ceiling.
Each unit section 3 (a-d, these symbols will hereinafter be omitted except when required for explanation) can be formed of a light transmitting material and, as shown in
When infrared light is radiated by a user/vehicle occupant to the light receiving portion 8a of the resin case 8, the infrared light is efficiently introduced into the light receiving portion 8a which can be formed of a material higher in refractive index than the atmosphere. In this case, since the light receiving portion 8a is formed in a convex lens shape having an appropriate curvature, the light is converged and travels through the interior of the resin case 8 and reaches the reflecting surface 8b. The infrared light is reflected by the reflecting surface 8b and changes its traveling course to the downward direction, i.e., toward the circuit board 6, in the illustrated state.
Since the light receiving element 4 is mounted on the circuit board 6, the infrared light introduced from the light receiving portion 8a of the resin case 8 eventually reaches the light receiving element 4, which then comes into operation. As a result, unlocking (or locking) is performed by the processing circuit 10 and, at the same time, the light emitting element 5 mounted in the same unit section 3 can be lit to inform a user/vehicle occupant that the requested door was unlocked.
Although the above description was in reference to the operation of one unit section 3 in a four door device, there are other types of vehicles that have a different number of doors, e.g., 2- or 5-door vehicle, etc. The number of unit sections 3 can correspond to the number of doors in a given vehicle. In addition, there are users who may want to unlock the engine hood (or front lid) and the rear lid (or trunk lid) with use of a keyless entry system. Therefore, the number of the unit section 3 that can be provided can be changed to account for such desires.
However, as the number of the unit sections 3 increases, it may become difficult to radiate infrared light accurately to only one unit section 3 which performs a requested function. Moreover, the leakage of light between the unit sections 3 may increase which may result in a malfunction such as two locks/keys operating simultaneously. To avoid such an inconvenience, as shown in
According to the above description the light emitting element 5 lights up when a door lock or the like is locked or unlocked. However, a study of actual vehicular working conditions shows that while a lock is usually locked during parking or stopping in a parking lot or the like, that locking is also sometimes done when the vehicle is running. Therefore, a change may be made such that the light emitting element 5 lights up during unlocking and goes out during locking.
According to the presently disclosed subject matter, as described above, each door can be independently opened and closed in principle, whereby it is possible to avoid the occurrence of all the doors being unlocked even when only the driver gets in the vehicle. The problem in which a vehicle is operated or is left running with all (or some) of the doors left unlocked without the driver becoming aware of this condition can be prevented.
In addition, since the announcement of locking and unlocking is made by turning ON and/or OFF of light, it is possible to reduce nuisance to neighbors even late at night and the influence of ambient conditions such as ambient brightness can be diminished because the lighting environment of the light emitting element can be the interior of the vehicle. Besides, by adopting a light emitting element 5 having a specific color, it is possible to make positive distinction from natural light and hence possible to confirm locking and unlocking in a positive manner.
Further,
While there has been described what are at present considered to be exemplary embodiments of the invention, it will be understood that various modifications may be made thereto, and it is intended that the appended claims cover such modifications as fall within the true spirit and scope of the invention. All conventional art references described above are herein incorporated in their entirety by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2007-091245 | Mar 2007 | JP | national |
