The present invention contains subject matter related to Japanese Patent Application No. 2008-049261 filed in the Japanese Patent Office on Feb. 29, 2008, the entire contents of which is incorporated herein by reference.
1. Field of the Disclosure
The present invention relates to a keyless entry device which locks and unlocks a door by performing communication between a vehicle-side device and a portable device, and particularly to a keyless entry device which generates an electric field in a human body by a transmission signal and detects the generated electric field to perform communication between a vehicle-side device and a portable device.
2. Description of the Related Art
Keyless entry devices include a vehicle-side device provided in a vehicle such as an automobile, and perform wireless communication between the vehicle-side device and a portable device carried by a user, to lock and unlock a door when the identification succeeds. There have been proposed keyless entry devices which perform communication between a vehicle-side device and a portable device with a human body interposed therebetween.
As a keyless entry device employing electric field communication, the present applicant proposes a device described in Japanese Patent Application No. 2006-230014 (Cross-Referenced U.S. patent application Ser. No. 11/888,718). The keyless entry device includes different electrodes provided on the sides of a surface (outer side) and a back surface (inner side, vehicle body side) of a door handle provided on a door of a vehicle and performs communication via the finger of the human body during the operation of the door handle to perform the identification and the like between a portable device and a vehicle-side device.
As the door handle, a door handle in which a handle body having a flap shape is pulled up, a door handle in which a handle body having a flap shape as above is pulled in a right or left direction, a door handle in which a grip portion having a grip shape is held and pulled to the front side, or the like is generally employed. In the above Japanese Patent Application No. 2006-230014, the keyless entry device is applied to a door handle including a grip-type grip portion.
When the door is opened, the door handle including the grip-shaped grip portion is operated to be pulled by inserting the finger into the inner side of the grip portion, and when the door is closed, the door handle is operated to press the outer side of the grip portion with the hand.
As shown in
When a signal is sent from the portable device 51, the signal is transmitted to a vehicle-side device 50 via the human body 52 and the vehicle-side electrode 55. However, since the equivalent circuit having C1 is formed between the vehicle-side electrode 55 and the vehicle body 53, the signal is also transmitted to the side of C1. In a conventional keyless entry device employing electric field communication, the electrode has a flat plate shape where a surface and a back surface of the grip portion 54 have the same size. Accordingly, when the grip portion is operated to be pulled by inserting the finger into the inner side of the grip portion 54, the vehicle body and the electrode on the side of the back surface of the grip portion 54 are close to each other, and the human body 52 is present therebetween. Thus, C1 shown in
A keyless entry device according to the invention performs communication between a portable device and a vehicle-side device provided in a vehicle. The portable device includes a portable device controller which performs communication of a signal for identification and a portable device electrode which induces an electric field generated by the signal from the portable device controller in a human body. The vehicle includes on a door a door handle provided with a grip portion having a grip shape, the grip portion of the door handle is provided with a vehicle-side electrode which detects the electric field induced in the human body by the portable device electrode, and the vehicle is provided with a vehicle-side controller to which the signal is input by the electric field detected by the vehicle-side electrode and which performs the identification of the signal. The vehicle-side electrode has at least two of a first face, a second face, an upper face and a lower face, where the first face is opposed to a vehicle body face of the vehicle, the second face is opposed to the vehicle body face of the vehicle and disposed at a position more distant from the vehicle body than the first face, and the upper face and the lower face are orthogonal to the first face and the second face and parallel to each other. The vehicle-side electrode is composed of the faces other than the first face or formed to have the first face having a smaller area than other faces.
In the keyless entry device according to the invention, the vehicle-side electrode has the first face and the second face and the first face is formed to be shorter than the second face to reduce an area.
In the keyless entry device according to the invention, the grip portion is provided with supporting portions at both ends thereof, each of which is connected to the vehicle body, the supporting portion at one end of the grip portion includes a rotation center portion, the supporting portion at the other end of the grip portion is supported to be freely pulled out of the vehicle body to the outside, and the first face of the vehicle-side electrode is disposed to be close to the other end of the grip portion.
In the keyless entry device according to the invention, the vehicle-side electrode is composed of the faces other than the first face and has the upper face and the lower face, and the upper face and the lower face are connected to each other by a connecting face which is opposed to or orthogonal to the vehicle body.
In the keyless entry device according to the invention, the upper face and the lower face are formed in a triangle shape having an apex facing the vehicle body.
In the keyless entry device according to the invention, the grip portion is provided with supporting portions at both ends thereof, each of which is connected to the vehicle body, the supporting portion at one end of the grip portion includes a rotation center portion, the supporting portion at the other end of the grip portion is supported to be freely pulled out of the vehicle body to the outside, and apexes of the upper face and the lower face are disposed to be close to the other end of the grip portion.
In the keyless entry device according to the invention, the vehicle-side electrode has the second face and the second face has a slit formed at one end thereof.
In the keyless entry device according to the invention, the grip portion is provided with supporting portions at both ends thereof, each of which is connected to the vehicle body, the supporting portion at one end of the grip portion includes a rotation center portion, the supporting portion at the other end of the grip portion is supported to be freely pulled out of the vehicle body to the outside, and the slit of the second face is formed at one end of the grip portion.
According to the keyless entry device of the invention, the vehicle-side electrode has at least two faces from among the first face which is opposed to the vehicle body face of the vehicle, the second face which is opposed to the vehicle body face of the vehicle and disposed at a position more distant from the vehicle body than the first face, and the upper face and the lower face which are orthogonal to the first face and the second face and parallel to each other. Since the vehicle-side electrode is composed of the faces other than the first face or formed to have the first face having a smaller area than other faces, the face of the vehicle-side electrode, which is opposed to the vehicle body face, can be distantly positioned, and the face of the vehicle-side electrode, which is perpendicular to the vehicle body face, can be closely positioned, or the face of the vehicle-side electrode, which is opposed to the vehicle body face, can be reduced. In addition, capacitance generated between the vehicle body and the vehicle-side electrode with the finger interposed therebetween can be reduced and thus loss of the signal transmission can be reduced.
Further, according to the keyless entry device of the invention, the vehicle-side electrode has the first face and the second face and the first face is formed to be shorter than the second face to reduce an area. Accordingly, only by reducing the size of the face of the vehicle-side electrode, which is close to the vehicle body face, capacitance generated between the vehicle body and the vehicle-side electrode with the finger interposed therebetween can be reduced and the vehicle-side electrode can be easily formed.
Furthermore, according to the keyless entry device of the invention, the first face of the vehicle-side electrode is disposed to be close to the end opposite to the rotation center portion of the grip portion. Accordingly, the area of the electrode on the side that is not touched with the hand in the grip portion is reduced and the area opposed to the vehicle body is thus reduced, and the area of the electrode on the side that is held increases. Therefore, loss can be suppressed and the signal can be more efficiently transmitted.
Moreover, according to the keyless entry device of the invention, the vehicle-side electrode is composed of the faces other than the first face and has the upper face and the lower face, and the upper face and the lower face are connected to each other by a connecting face which is opposed to or orthogonal to the vehicle body. Accordingly, the vehicle-side electrode is easily formed by being bent.
In addition, according to the keyless entry device of the invention, the upper face and the lower face are formed in a triangle shape having an apex facing the vehicle body. Accordingly, by reducing as much as possible the portion of the vehicle-side electrode, which is close to the vehicle body face, loss of the signal transmission can be further reduced.
Further, according to the keyless entry device of the invention, the apexes of the upper face and the lower face are disposed to be close to the end opposite to the rotation center portion of the grip portion. Accordingly, the area of the electrode on the side that is not touched with the hand in the grip portion is reduced and the area of the electrode on the side that is held increases. Therefore, signal loss can be suppressed and the signal can be more efficiently transmitted.
Further, according to the keyless entry device of the invention, the vehicle-side electrode has the second face and the second face has a slit formed at one end thereof. Accordingly, the area which is opposed to the vehicle body can be reduced, and the face of the vehicle-side electrode, which is opposed to the finger, can be increased. Therefore, signal loss is reduced and the transmission efficiency can be balanced.
Furthermore, according to the keyless entry device of the invention, the slit of the second face is formed at the end on the side of the rotation center portion of the grip portion. Accordingly, the area of the electrode on the side that is not touched with the hand in the grip portion is reduced and the area opposed to the vehicle body is thus reduced, and the area of the electrode on the side that is held with the hand in the grip portion increases. Therefore, signal loss can be suppressed and the signal can be more efficiently transmitted.
An embodiment of the invention will be described in detail on the basis of the drawings.
In
The supporting portion 32 provided at one end of the grip portion 31 is supported rotatably about a rotation center portion 32a in the door 1a. The supporting portion 33 provided at the other end of the grip portion 31 is supported to be freely pulled out of the door 1a.
When the user carrying the portable device 3 holds and operates the grip portion 31 to be pulled in order to open the door 1a from the outside of the vehicle, the electric field induced in the human body by the portable device electrode 22 of the portable device 3 can be detected by the vehicle-side electrode 12 in the grip portion 31. When the identification succeeds, the door 1a is unlocked. On the other hand, when the user carrying the portable device 3 operates the grip portion 31 to be pressed in order to close the door 1a, the electric field induced in the human body by the portable device electrode 22 of the portable device 3 can be detected by the vehicle-side electrode 12 in the grip portion 31. When the identification succeeds and the door 1a is closed, the door 1a is locked. In this case, the vehicle-side device 2 performs an unlocking operation when the door 1a is locked, and performs a locking operation when the door 1a is closed while being unlocked.
The vehicle-side controller 10 includes a determination portion 10a which identifies the signal from the portable device 3, storage means 10b which temporarily stores data, and an input portion 1c which demodulates the signal on the basis of the detection of the electric field that is performed by each electrode and causes the storage means 10b to store the signal. The vehicle-side controller 10 can always receive the signal from the vehicle-side electrode 12.
The memory 11 provided in the vehicle-side device 2 stores a unique ID of the portable device 3 for the vehicle 1. The determination portion 10a of the vehicle-side controller 10 matches the ID included in the signal temporarily stored in the storage means 10b with the ID stored in the memory 11. When the IDs are matched, the determination portion determines that the identification succeeds, and when the IDs are not matched, the determination portion determines that the identification does not succeed.
Next, the structure of the vehicle-side electrode 12 provided in the grip portion 31 will be described in detail.
As shown in
The vehicle-side electrode 12 can obtain larger output by increasing as much as possible an area of a face opposed to the finger while the grip portion 31 is held with the hand to be operated, or reducing the distance with the finger. On the other hand, capacitance generated between a vehicle body face and the vehicle-side electrode with the finger interposed therebetween can be reduced and thereby reducing the loss of signal transmission by not making or reducing a face opposed to the vehicle body face or keeping the face as far away from the vehicle body face as possible. Accordingly, the vehicle-side electrode 12 according to this embodiment is constituted by faces other than the first face 40 among the four faces shown in
In this example, the vehicle-side electrode 12 has the first face 40 and the first face is shorter than the second face 41. That is, the first face 40 is formed to have a smaller area than the second face 41. Accordingly, the face of the vehicle-side electrode 12 opposed to the vehicle body face is made relatively small and capacitance generated between the vehicle body and the vehicle-side electrode with the finger interposed therebetween can be reduced. Thus, loss of the signal transmission can be reduced. In addition, since the vehicle-side electrode 12 of this example has both of the first face 40 and the second face 41, the vehicle-side electrode is closely opposed to a finger in either of the case where the grip portion 31 is held while the door 1a is opened, and the case where the grip portion 31 is pressed in order to close the door 1a. Therefore the communication can be securely performed.
In
As described above, when the vehicle-side electrode 12 is constituted by only the faces other than the first face 40 closely opposed to the vehicle body face, capacitance generated between the vehicle body and the vehicle-side electrode with the finger interposed therebetween can be reduced. Thus, loss of the signal transmission can be reduced. In addition, since the second face 41 is distant from the vehicle body face, the capacitance generated between the vehicle body and the vehicle-side electrode with the finger interposed therebetween is small. Furthermore, since the upper face 42 and the lower face 43 are faces in a direction perpendicular to the vehicle body face, the capacitance generated between the vehicle body and the vehicle-side electrode with the finger interposed therebetween is also small. While the vehicle-side electrode 12 of this example does not include the first face 40, it includes the second face 41, the upper face 42 and the lower face 43. Therefore, the vehicle-side electrode is opposed to the finger and can perform the communication when the door 1a is opened and closed.
The apexes 44 are arranged to be close to one side in one of the right and left directions of the vehicle-side electrode 12. That is, among three sides constituting each of the upper face 42 and the lower face 43, one of two sides, other than the side in contact with the second face 41, is shorter than the other. Also in
Furthermore, the slit 46 is formed on the side in which the supporting portion 32 including the rotation center portion 32a in the grip portion 31 is provided and the second face 41 is disposed to be close to the left side of the drawing in which the supporting portion 33 is provided. As described above, the user performs the operation by mostly holding with the hand the portion near the left side of the drawing in which the supporting portion 33 of the grip portion 31 is provided. Accordingly, the area of the vehicle-side electrode 12 opposed to the finger can be sufficiently ensured by the second face 41 disposed to be close to one side.
The embodiments of the invention have been described as above. The invention is not limited to the embodiments and can be modified in various forms without departing from the technical spirit and scope of the invention. For example, in this embodiment, the first face 40, the second face 41, the upper face 42 and the lower face 43 intersect with each other in the grip portion 31, as shown in
However, one or more of the first face 40, the second face 41, the upper face 42 and the lower face 43 may overlap with the surface of the grip portion 31 and the vehicle-side electrode 12 may be exposed to the surface of the grip portion 31.
Number | Date | Country | Kind |
---|---|---|---|
2008-049261 | Feb 2008 | JP | national |