Electronic vehicle security system devoid of lock cylinders

Abstract

A vehicle security system includes a vehicle ignition switch, a door lock actuator, a primary vehicle entry and ignition control circuit, a backup vehicle access control circuit and a key including a principal vehicle control subsystem and a backup vehicle entry circuit. Advantageously, the system is devoid of any ignition lock cylinder, any door lock cylinder and any key blade thereby reducing vehicle manufacturing costs. A related method is also provided.

Claims

1. A vehicle security system, comprising: a vehicle ignition switch; a door lock actuator; a primary vehicle entry and ignition control circuit connected to said ignition switch and said lock actuator, wherein said primary vehicle entry and ignition control circuit includes a receiver and a body control module powered by a primary vehicle power supply; a backup vehicle access control circuit connected to said lock actuator, wherein said backup vehicle access control circuit includes a backup vehicle access controller and a backup power supply for powering said backup vehicle access controller; and a key including a principle vehicle control circuit and a backup vehicle entry circuit wherein said vehicle security system is devoid of any ignition lock cylinder, any door lock cylinder and any key blade, wherein said principle vehicle control circuit includes a first actuator, a controller, a transmitter and a principle power source, and wherein said backup vehicle entry circuit includes a second actuator, a backup controller and a backup power source.

2. The system of claim 1, wherein said vehicle security system further includes a passive entry circuit.

3. The system of claim 2, wherein said passive entry circuit includes a presence sensor, a passive entry control module and a low frequency transmitter.

4. The system of claim 3, wherein said key further includes a low frequency receiver.

5. The system of claim 1, wherein said key includes a key fob housing having a plurality of control buttons.

6. The system of claim 5, wherein said key includes a common ignition switch engagement feature.

7. The system of claim 6, wherein said common ignition switch engagement feature is formed by said key fob housing.

8. The system of claim 7, wherein said key further includes a transponder and an associated winding and said ignition switch includes an induction coil.

9. The system of claim 5, wherein said key fob housing and said plurality of control buttons are identical whether said key is for a passive entry passive start vehicle or non-passive entry passive start vehicle.

10. A motor vehicle incorporating said vehicle security system of claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The accompanying drawings incorporated herein and forming a part of the specification, illustrate several aspects of the vehicle security system and together with the description serve to explain certain principles thereof. In the drawings:

(2) FIG. 1 is a perspective view of the front of a key fob used in conjunction with the vehicle security system.

(3) FIG. 2 is a schematic block diagram of the electronic components of a nPEPS key fob consistent with the vehicle security system.

(4) FIG. 3 is a schematic block diagram of the electronic components of the vehicle security system of a nPEPS vehicle responsive to the nPEPS key illustrated in FIG. 2.

(5) FIG. 4 is a schematic block diagram of the electronic components of a key fob for a PEPS vehicle.

(6) FIG. 5 is a schematic block diagram of the electronic components of the vehicle security system for a PEPS vehicle operated by the PEPS key fob illustrated in FIG. 4.

(7) Reference will now be made in detail to the present preferred embodiment of the vehicle security system, examples of which are illustrated in the accompanying drawings.

DETAILED DESCRIPTION

(8) Reference is now made to FIGS. 1-5, which considered together, fully illustrate the electronic vehicle security system 10. A key 12 for the system 10 is illustrated in FIG. 1. The key 12 includes a key fob housing 14 and a plurality of control buttons 16.sub.1-16.sub.5. In the illustrated embodiment, the control button 16.sub.1 is depressed to lock a door or the doors of the associated vehicle V. Control button 16.sub.2 is depressed to unlock a door or the doors of the vehicle V. Control button 16.sub.3 is depressed in order to unlock the trunk lid of the vehicle V. Control button 16.sub.4 is depressed in order to cause the vehicle to sound an emergency alarm. Finally, control button 16.sub.5 is depressed to utilize the backup system to unlock the door of the vehicle in a manner that will be described in greater detail below.

(9) As further illustrated in FIG. 1, the key 12 also includes a common ignition switch engagement feature 18 which may be inserted into and received in the ignition switch 44 of the nPEPS vehicle V as described in greater detail below in order to manually start and operate the vehicle when desired. In the illustrated embodiment the common ignition switch engagement feature 18 comprises a projecting rectangular lug with two opposing notches 20. Here it should be appreciated that the feature 18 may assume substantially any desired shape so long as the feature is common. By “common” it is meant that the feature 18 is standard equipment and may be received in substantially any ignition switch 44 on substantially any nPEPS vehicle V produced by that manufacturer. This commonality functions to reduce production costs without sacrificing security in any manner.

(10) In one particularly useful embodiment, the key fob body or housing 14 and the common ignition switch engagement feature 18 are integrally molded together. More specifically, the key fob housing 14 and feature 18 are assembled from two molded sections 22a and 22b that are secured together after inserting the electronic components of the key 12 which are held within an internal cavity formed by those sections.

(11) Reference is now made to FIG. 2 schematically illustrating the electronic components found in a key 12 to be used to control the operation of a vehicle V by means of a nPEPS system.

(12) More specifically, the key 12 includes a housing 14 which contains a principal vehicle control circuit 24 and a backup vehicle entry circuit 26. More specifically, the principal vehicle control circuit 24 includes a microprocessor controller or electronic control unit (ECU) 28, a cooperating actuator, such as push button 16.sub.2, and a radio frequency transmitter 32 incorporating an antenna 34. As illustrated, the principal vehicle control circuit 24 is powered by a principal power source 36 identified in the figure as the “primary battery”.

(13) The backup vehicle entry circuit 26 comprises a backup controller 38 in the form of a microprocessor controller or ECU, and a second actuator in the form of a push button 16.sub.5 for activating the controller 38. As illustrated, the backup vehicle entry circuit 26 is powered by a backup power source 42 identified in the drawing figure as the “backup battery”.

(14) The key 12 illustrated in FIG. 2 allows the owner or operator to control entry into and operation of the vehicle V schematically illustrated in FIG. 3. That vehicle includes a vehicle ignition switch 44 and at least one door lock actuator. In the illustrated embodiment, the vehicle V includes four door lock actuators 46.sub.1-46.sub.4. Actuator 46.sub.1 operates the lock on the front left-hand or driver's door. Actuator 46.sub.2 operates the lock on the front right-hand or passenger door. Door actuator 46.sub.3 operates the lock on the rear left-hand side door while actuator 46.sub.4 operates the lock on the rear right-hand door.

(15) As further illustrated in FIG. 3, the vehicle also includes a primary vehicle entry and ignition control circuit 48 including a body control module or ECU 50 and a radio frequency receiver 52 connected to an antenna 54. The primary vehicle entry and ignition control circuit 48 is powered by the primary vehicle power supply such as a battery 56. In addition vehicle V includes a backup vehicle access circuit 57 including a backup vehicle access controller or ECU 58 powered by a backup power supply 60.

(16) In operation, the vehicle operator approaches the vehicle V, holds the key 12 and depresses the control button 16.sub.2 to unlock the driver's door of the vehicle. When the button 16.sub.2 is depressed, the controller 28 activates the radio frequency transmitter 32 to transmit a security code over the antenna 34 toward the vehicle V. The radio frequency receiver 52 of the primary vehicle entry and ignition control circuit 48 within the vehicle V receives the code and sends it to the body control module (BCM) 50 for entry authorization. If the BCM 50 recognizes the code as authentic to the vehicle, the BCM 50 sends a signal to the door lock actuator 46.sub.1 which is then activated to unlock the driver's side door. After entering the vehicle, the operator inserts the common ignition switch engagement feature 18 into the receiver of the ignition switch 44 and turns the ignition past the on position to the start position. When this is done an induction coil 45 in the ignition switch 44 sends out an electromagnetic field of energy. The windings 64 absorb that energy and power the transponder 66 in the key 12 to emit a coded signal. That coded signal may be an alphanumeric sequence which functions as an identification code. The induction coil 45 reads that signal and sends it to the BCM 50. In the event the BCM 50 recognizes the signal as an operator authorized code, BCM 50 initializes other electronic components of the vehicle to allow the starting of the vehicle V and continued operation thereof.

(17) The above description assumes that the principal power source 36 in the key 12 has the necessary charge to allow the principal vehicle control circuit 24 to operate normally. In the event the principal power source 36 does not have the necessary charge to provide normal function of the principal vehicle control circuit 24, when the operator depresses the control button 16.sub.2, nothing will happen and the vehicle door will remain locked. In this situation the operator then depresses the backup control button 16.sub.5. The backup power source 42 provides the necessary power to the backup vehicle entry circuit 26 for the backup controller 38 to activate the transmitter 32 causing it to send the security code over the antenna 34 to the vehicle receiver 52 thereby initiating the unlocking of only the driver's door through backup door controller (58). Thus, it should be appreciated that the backup vehicle entry circuit 26, and its isolated power source 42 provide an electronic backup mechanism allowing entry into the vehicle V even when the primary battery 36 is discharged or is not functioning properly. It is important to note the backup system will not allow the car to start if the ECU or power supply battery (56) are not working. It only allows the user to get inside the car and take protection from the elements.

(18) In the event, the primary vehicle power supply 56 has lost charge for any reason and is unable to power the primary vehicle entry and ignition control circuit 48, the backup vehicle access circuit 57 will unlock the driver's door by means of actuator 46. More specifically, the receiver 52 will transmit the security code received from the transmitter 32 to the backup controller 58. Upon recognizing the code as authentic, the controller 58 will send a signal to the door lock actuator 46, to unlock the driver's door and allow access to the vehicle V.

(19) Reference is now made to FIG. 4 which illustrates a key 14 for a vehicle equipped with a PEPS system. The key 14 includes a principal vehicle control circuit 70 and a backup vehicle entry circuit 72.

(20) The principal vehicle control circuit 70 includes a controller 74 connected to a radio frequency transmitter 76, having an antenna 78, and a low-frequency receiver 80, connected to an antenna 82. The controller 74 is activated by the first actuator or push button 16.sub.2. As further illustrated, the principal vehicle control circuit 70 is powered by the principal power source or primary battery 84.

(21) The backup vehicle entry circuit 72 includes a backup controller 86 activated by the second actuator or push button 16.sub.5 and powered by the backup power source or battery 88.

(22) Reference is now made to FIG. 5 illustrating the vehicle V with a PEPS system that cooperates with the key 12 illustrated in FIG. 4.

(23) As illustrated, the vehicle V includes an ignition switch 90 and at least one door lock actuator. In the illustrated embodiment four door lock actuators 92.sub.1-92.sub.4 are provided. Door lock actuator 92.sub.1 activates the lock on the front left-hand or driver's door. Door lock actuators 92.sub.2-92.sub.4 are connected to the other doors of the vehicle V.

(24) The vehicle V also includes a primary vehicle entry and ignition control circuit 94 comprising the body control module or ECU 96 and the radio frequency receiver 98. The primary vehicle entry and ignition control circuit 94 is powered by the primary vehicle battery 100.

(25) The vehicle V also includes a backup vehicle access or driver door circuit 101 which comprises the backup controller 102 which is powered by a backup battery 104.

(26) Still further, the vehicle V includes a PEPS operating system or passive entry circuit 106 including a PEPS control module or ECU 108, a low-frequency transmitter 110 and a presence, touch or capacitive sensing system or sensor 112.

(27) In normal operation, the operator approaches the vehicle V and inserts his hand into the door handle cavity of the driver's side door with the intention of pulling the handle. This breaks a capacitive field and the presence sensor 112 sends a signal to the PEPS control module 108. In response the PEPS control module 108 sends a signal causing the LF transmitter 110 to admit a low-frequency signal. The LF receiver 80 in the PEPS key 14 detects that signal and then sends an appropriate signal to the controller 74 which in turn sends a control signal to the RF transmitter 76 which transmits a key code over the antenna 78 toward the vehicle V. The vehicle receiver 98 receives the signal and sends it to the BCM 96 to determine the signal authenticity. Upon confirming the proper key code, the BCM sends a signal to the door lock actuator 92.sub.1 to unlock the lock on the driver's side door.

(28) The passenger then completes the seamless opening the door with the handle, gets into the vehicle V and closes the door. The BCM 96 then establishes through sensors that the key 12 is inside of the vehicle. When the driver pushes the ignition button 114 of the ignition switch 90, the BCM 96 or other engine start electronic control unit allows the engine to start after again confirming the key code.

(29) In the event the primary battery 84 of the key 12 does not have a sufficient charge to drive the principal vehicle control subsystem 70, when the operator depresses the push button 16.sub.2, nothing happens. In this situation the operator may then depress the backup push button 16.sub.5 activating the back controller 86 powered by the backup battery 88. Here it should be noted that the electrical circuit powered by the backup battery 88 is isolated from that powered by the primary battery 84. Upon pushing the backup push button 16.sub.5, the backup controller 86 is activated, sending a control signal to the RF transmitter 76 causing the key code to be transmitted by the transmitter through the antenna 78 toward the vehicle V. The RF receiver 98 receives the signal and sends it to backup driver door controller (102) which in turn unlocks only the front LH latch 92.sub.1. This will only allow the driver to enter the vehicle and start the vehicle if the power supply (100) and ECU (96) are operational and can confirm the key code from the key-fob.

(30) If the primary power supply or battery 100 of the vehicle V is dead or sufficiently discharged, the BCM/ECU 96 will not operate. However, the backup vehicle access controller 102 will still be powered by the backup battery 104 so that any unlock signal sent by the transmitter 76 of the key will be received by the receiver 98. The key code will then be confirmed by the backup vehicle entry controller 102 and that controller will send an appropriate signal to the lock actuator 92.sub.1 to unlock the driver door thereby allowing the operator access to the vehicle. This will only allow the driver to enter the vehicle and but NOT start the vehicle.

(31) In summary, numerous benefits result from employing the vehicle security system 10 disclosed this document. Significantly, a vehicle V is equipped with the electronic security system and any key blade and associated door key lock cylinders and ignition key lock cylinders are omitted. Instead a key blade is provided with a common ignition switch engagement feature 18 which will fit in the ignition switch of all nPEPS vehicles. This commonality reduces production costs of the key fob 14 and allows the manufacturer to use a single key fob body designed for both PEPS and nPEPS vehicles.

(32) It should be appreciated that these benefits are achieved without compromising vehicle security. This is because a matching electronic key code must be confirmed before the vehicle will grant entry or the ignition will operate. Still further, the backup systems 26, 72 of the key and 58, 102 of the vehicle ensure that the door lock actuators 46.sub.1, 92.sub.1 may be operated under substantially any conditions to allow access to the vehicle. It should also be appreciated that the strength of the signal transmitted by the key transmitter 32, 76 may be monitored by the BCM 50, 96. If the signal is weaker than a predetermined level, the BCM 50, 96 will provide notice to the vehicle operator to charge or change the battery in the key 12 through a display module (not shown) in the vehicle V or via wireless connection by email or text message to the operator's computer or telephone. Similarly, the BCM 50, 96 may monitor the backup power supply 60, 104 for the same purpose and provide a similar notice if required.

(33) The foregoing has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the embodiments to the precise form disclosed. Obvious modifications and variations are possible in light of the above teachings. All such modifications and variations are within the scope of the appended claims when interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.