Abstract:
An automated child safety unlocking system for automobiles which disengages the child safety locks and unlocks the doors at appropriate times during events such as vehicle crashes. The vehicle ECU continually monitors the status of the vehicle to check if a crash event has occurred via various methods such as the status of airbag deployment, accelerometers placed in the car, and crumple points. In the event of a crash the vehicle ECU transmits one of at least two CSL command signals a child safety lock ECU. The command signals are each specific to an event severity and event type, and the child safety lock ECU then interprets the signal and acts according to the signal type. If the data interpreted indicates a crash, the child safety lock ECU unlocks the child safety locks, and if it does not determine a crash has not occurred, the locks remain engaged.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 62/059,519 filed Oct. 3, 2014. 
    
    
     FIELD OF THE INVENTION 
     The present invention is related to an automatic child safety lock release during an accident. 
     BACKGROUND OF THE INVENTION 
     “Child safety locks” are present on most vehicles. In particular, vehicles with a back seat have a manual release in the outer portion of the door which is exposed by opening of the door. Typically, there is a recessed switch in the door that is actuated by a screwdriver, or key, or by hand, and switched manually from an open position where the locks function in a normal manner, or a locked position where the exposed locks in a rear door cannot be manually manipulated by a rear seat occupant. 
     The purpose for this type of lock is to avoid undesired opening by a child or other rear seat occupant of the rear door which might place the child or occupant at risk. Additionally, the door cannot be opened from the outside which also protects the child from external unwanted entries by strangers or the like. 
     While this acts to protect the child or other occupant during normal operation of the vehicle, the child locks can produce a potentially dangerous situation. For example, if there is an accident and the vehicle catches on fire, the child or any occupant from the rear seat cannot be removed from the vehicle by opening the door from the inside or outside unless the door is unlocked from a different location like a key fob or door unlock switch near front seats. In the case of a rollover accident or other accident, the passenger cannot exit nor potentially can a rescue person open the rear door for removal of the occupant. 
     Therefore, there is a need in the art to provide an automated child safety device that opens upon impact. 
     SUMMARY OF THE INVENTION 
     The present invention relates to an automated child safety unlocking system for automobiles which disengages the child safety locks and unlocks the doors at appropriate times during events such as vehicle crashes. The system includes two or more crash sensors each configured to generate a crash signal upon detection of an event, such as the vehicle striking an object. A vehicle ECU is configured to receive the crash signal from each of the two or more crash sensors and then transmit one of at least two CSL command signals. The vehicle ECU continually monitors the status of the vehicle to check if a crash event has occurred via various methods such as the status of airbag deployment, accelerometers placed in the car, and crumple points. The at least two CSL command signals are each specific to an event severity and event type, where one of at least two CSL command signals generated by the vehicle ECU is transmitted with general signals over a general vehicle communication bus. The signal generated by the vehicle ECU is continually passed to a child safety lock ECU which then interprets the signal and acts according to the signal. If the data interpreted indicates a severe crash, the child safety lock ECU unlocks the child safety locks immediately, and if it is determined a minor crash or no crash has occurred, the locks remain engaged. 
     The child safety lock ECU is configured to receive the general signals transmitted through the general vehicle communication bus and filter the one of at least two CSL command signals from the general vehicle communication bus signal. The child safety lock ECU engages or disengages a child safety lock actuator depending on the one of at least two CSL command signals received by the child safety lock ECU. 
     The system becomes engaged (i.e. the ECUs are activated and begin transmission) upon start-up of the vehicle and are subsequently re-initialized upon successive start-ups. 
     Various other data is transmitted along with the signals from the vehicle ECU provide different functionality. A rolling counter is employed in order to ensure consistent transmission of data from the ECUs. General data on the operation of the ECUs is transmitted concerning the operating parameters of the ECU such as, but not limited to, voltages, temperatures, and number of transmissions by the ECUs. This data can be interpreted in order to provide optimal operation by the ECU. Checksum protection is transmitted in order to verify the entire signal has been sent from the vehicle ECU to the child safety lock ECU and prevent miscommunication between the ECUs. An ECU identification signal is employed in order to establish the identity of the ECU which is currently transmitting. 
     Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a general schematic diagram of an automated child safety unlocking system in accordance with one embodiment of the invention; 
         FIG. 2A  is a graphical illustration of an analog control signal for use in the automated child safety unlocking system in accordance with another embodiment of the invention; 
         FIG. 2B  is a graphical example of an analog pulse width modulated control signal for use in connection with the automated child safety unlocking system; 
         FIG. 3  is a schematic diagram of the automated child safety unlocking system in accordance with a second embodiment of the present invention; 
         FIG. 4A  is a schematic diagram of digital communications between the vehicle ECU and the child safety lock ECU; 
         FIG. 4B  is a schematic diagram of digital communications between the vehicle ECU and the child safety lock ECU; 
         FIG. 5  is a decision box diagram of the automated child safety unlocking system in accordance with the present invention; 
         FIG. 6  is a decision box diagram showing an operational overview of the automated child safety unlocking system in accordance with the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. 
     Referring now to the Figures, with particular reference to  FIG. 1 , a schematic diagram of an automated child safety unlocking system  10  is shown. The child safety unlocking system  10  uses two or more crash sensors  12  that are each configured to generate a crash signal upon detection of an event. The two or more crash sensors  12  are located at various portions on a vehicle body. The crash sensors  12  can include pressure sensors, accelerometers, light sensors, or virtually any other type of sensor capable of sensing or detecting an event such as a vehicle collision with an object or other vehicle. Depending upon the number of crash sensors  12  that generate a crash signal  13 , the child safety unlocking system can be configured to determine the severity of a vehicle impact using the information or crash signal or the number or type of crash signal generated from the crash sensors  12 . The crash sensors  12  are configured to generate the crash signal  13  only upon detection of an event, where if no event is detected, no signal will be sent. The crash sensors  12  are placed at different locations on the vehicle exterior and interior of the vehicle cabin. Examples of sensor locations and functions include front, side and rear sensors, brake sensors, airbag sensors and virtually any other type of sensor suitable for detecting an event, such as a vehicle crash. 
     Crash sensors  12  generate a crash signal to a vehicle ECU  14  that is configured to receive a crash signal from each of the sensors  12 . The vehicle ECU  14  is then configured to transmit one of at least two child safety lock (CSL) command signals  16 . The type of CSL command signal transmitted is specific to an event severity and event type, which can be determined by the number of crash signals  13  or the types of crash sensors  12  transmitting the crash signal  13 . The CSL command signals  16  are generated by the vehicle ECU  14  to a child safety lock ECU  18 . 
     The transmission of the CSL command signals  16  can be done by an independent communication bus directly coupled to the child safety lock ECU  18  or, in a preferred embodiment of the invention; the vehicle ECU  14  transmits the CSL command signals  16  as part of the general signals over a general vehicle communication bus  20 . The general signals over the general vehicle communication bus  20  include other types of signals that go to other vehicle systems. This allows for a general or centralized arrangement of communication between the vehicle ECU  14  and the child safety lock ECU  18 , without having to provide a designated wiring or communication link. 
     The child safety lock ECU  18  is configured to receive the general signals transmitted through the general vehicle communication bus  20 . The child safety lock ECU  18  filters the one of at least two CSL command signals  16  from the general vehicle communication bus  20 . The child safety lock ECU  18  then selectively disengages a child safety lock actuator  22  in response to the type of CSL command signal  16  received by the child safety lock ECU  18 . Disengagement of the child safety lock actuator  22  can mean that the child safety features are disengaged so that the door can be unlocked by anyone inside of the vehicle. Additionally disengagement of the child safety lock actuator  22  also includes disabling the child safety lock features and unlocking the vehicle door so that someone from outside of the vehicle can open the unlocked door. 
     The engagement or disengagement of the child safety lock actuator  22  is controlled by the child safety lock ECU  18 . The child safety lock ECU  18  is configurable to adjust the amount of time before the child safety lock ECU  18  disengages the child safety lock actuator  22  depending upon the type of CSL command signal  16  transmitted by the vehicle ECU  14 . For example, if the child safety lock ECU  18  receives a CSL command signal  16  that indicates that the event severity was not very great or the type of event that occurred was not overly dangerous, then the child safety lock ECU  18  may forgo disengaging the child safety lock actuator  22 . Or, if the event severity or event type is such that it indicates that the crash is occurring for a certain duration or period of time, such as a multiple vehicle collision or vehicle roll over scenario, then the child safety lock ECU  18  may delay the disengagement of the child safety lock actuator  22  for a predetermined period of time that is programmed into the child safety lock ECU  18 , while in another example, if the event severity or event type was severe and the circumstances are known to indicate that the crash has ended, but there is imminent danger and person need to exit the vehicle, the child safety lock ECU  18  is preprogrammed to immediately disengage the child safety lock actuator  22  without any delay of time. This allows for the door to be immediately opened from the inside or outside. The amount of delay or action to be taken by the child safety lock ECU is all pre-programmable onto the child safety lock ECU and can be changed or adjusted depending upon the circumstances or known circumstances of a crash. 
     The communication between ECUx and ECUy (crash notification data) can be realized by one or a combination of the following types of communication:
         Digital: e.g. CAN, Flex-ray, LIN, Kline, etc.   Analog: Based on exceeding an analog threshold in the signal (positive or negative slopes);   Analog PWM: Based on an analog PWM signal.   Frequency/period can be configured based on needs.
 
It will be readily appreciated that combinations of these may be used for redundancy if necessary.
       

       FIGS. 2A and 2B  show examples of analog signals that are transmittable as the CSL command signal  16  between the vehicle ECU  14  and the child safety lock ECU  18 .  FIG. 2A  shows two analog signals implementing a positive pulse or negative pulse in the signal when a crash occurs. As shown a constant value signal is transmitted between the vehicle ECU  14  and the child safety lock ECU  18 . When an event is detected by the vehicle ECU  14  the analog signal, transmitted as the CSL command signal  16  can pulse positive, negative or both. Depending on if the signal pulses positive or negative will control whether the child safety lock ECU  18  engages or disengages the child safety lock actuator  22 . For example the child safety lock ECU  18  can be programmed to delay disengagement of the child safety lock actuator  22  for any programmable period of time such as 5, 10, 15, 20 seconds if the pulse is negative, which is programmed to indicate a severe or longer duration crash or event. In the same example the child safety lock ECU  18  can be programmed to immediately disengage the child safety lock actuator  22  if the pulse if positive, indicating a less severe of short duration crash or event. 
       FIG. 2B  shows an example of a pulse width modulated analog signal  48  that is transmittable as a CSL command signal  16  between the vehicle ECU  14  and the child safety lock ECU  18 . The signal  48  contains a first set of pulses  50  of varying interval and intensity, a second set of pulses  52  of varying interval and intensity and a third set of pulses  54  of varying interval and intensity. The child safety lock ECU  18  is programmable to monitor the pulse width modulated signal  48  and determine what type of event has occurred based on the set of pulses received and how the child safety lock actuator  18  is programmed to respond. For example the set of pulses  50  could indicate no action should be taken and the child safety lock actuator  22  should not change state because either no event has occurred or the type of event that has occurred does not warrant disengagement of the child safety lock actuator  22 . An example of such an event would be if a minor crash occurred and the driver might need to exit the vehicle, but would not want the child safety lock doors unlocked to keep children from exiting the vehicle where they would be exposed to passing traffic. The set of pulses  52  could indicate an event that is severe but short in duration and require the immediate disengagement of the child safety lock actuator  22 . Example could be a vehicle crash where the car has stopped moving but is on fire. The set of pulses  54  could indicate that a severe event has occurred that will be long in duration, therefore, there will be a delay before disengagement of the child safety lock actuator  22 . An example would be a crash where the vehicle rolls multiple times or a multi-vehicle crash. The way the child safety lock ECU  18  reacts to the different pulses is completely programmable to any desired action or duration before action takes place depending on a particular application or customer requirement. 
       FIG. 4  is a schematic diagram of digital CSL signals  16  transmitted between the vehicle ECU  14  and the child safety lock ECU  18 . As shown the top portion of the diagram schematically shows a digital signal  24  transmitted from the vehicle ECU  14  to the child safety lock ECU  18 , while the bottom portion of the diagram shows a digital signal  26  transmitted from the child safety lock ECU  18  to the vehicle ECU  14 . The digital signal  24  includes a transmitter identification portion  28  and a receiver identification portion  30 , which allows the child safety lock ECU  18  to identify that the digital signal  24  is coming from the vehicle ECU  14  and is intended for the child safety lock ECU  18 . This enables the child safety lock ECU  18  to filter the digital signal  24  from the other signals of the general communication bus  20 . The digital signal  24  also contains a rolling counter portion  32  that defines the size of the signal being transmitted. A general data portion  34  of the digital signal  24  contains information concerning the event status, severity and type. The general data portion is used by the child safety lock ECU  18  to determine when and whether to disengage the child safety lock actuator  22 . Additionally the general data portion  24  contains other data or information requests concerning but not limited to child safety lock actuator  22  status request, customer diagnostic request, child safety lock ECU  18  and child safety lock actuator  22  verification of test request. The digital signal  24  also contains a checksum protection portion  36  that allows the child safety lock ECU  18  to confirm that the entire message of the digital signal  24  was received. 
     When the general data portion  34  contains a request for information from the child safety lock ECU  18  or when the child safety lock ECU  18  is programmed to automatically send a signal to the vehicle ECU  14 , the digital signal  26  is transmitted. The digital signal  26  includes a transmitter identification portion  38  and a receiver identification portion  40 , which allows the vehicle ECU  14  to identify that the digital signal  26  is coming from the vehicle ECU  14  and is intended for the child safety lock ECU  18 , this enables the vehicle ECU  14  to filter the digital signal  26  from the other signals of the general communication bus  20 . The digital signal  26  also contains a rolling counter portion  42  that defines the size of the signal being transmitted. A general data portion  44  of the digital signal  26  contains information concerning the event status, severity and type. Additionally the general data portion  44  contains other data or information requests concerning but not limited to child safety lock actuator  22  status, customer diagnostic information, child safety lock ECU  18  and child safety lock actuator  22  verification of test response. The digital signal  26  also contains a checksum protection portion  46  that allows the child safety lock ECU  18  to confirm that the entire message of the digital signal  26  was received. 
       FIG. 3  depicts a second embodiment of the invention showing an automated child safety lock unlocking system  100  using the same reference numbers for identical components show in  FIG. 1 , with variations labelled with prime numbers. The automated child safety lock unlocking system  100  has the same crash sensors  12  as shown in  FIG. 1 , with crash signals  13  being transmitted directly to a child safety lock ECU  18 ′. The child safety lock ECU  18 ′ determines the type of crash and the appropriate time for disengaging the child safety lock actuator  22 . The present embodiment eliminates the need for having the vehicle ECU  14  and sending signals through the general communications bus  20  as described in  FIG. 1  above. 
     Referring now to  FIG. 5  a decision box diagram of the automated child safety unlocking system  10 ,  100  in accordance with the present invention where the steps outlining the monitoring the operation of the automated child safety unlocking system  10 ,  100  is functioning. At a start step  48  the vehicle ignition is turned on and the child safety lock system has gone through a check sequence as described below in  FIG. 6 . At decision step  50  “Has Crash Occurred/” the system  10 ,  100  determines if a crash has occurred. The term “crash” as used herein means any event that warrants a change in the child safety lock status. This determination is made by the vehicle ECU or the child safety lock ECU depending on the arrangement and programming of the controllers. If at the decision step  50  it is determined that no crash has occurred then the child safety lock ECU will move to a “Do Nothing” step  52  and take no action to disengage the child safety lock actuator. The system  10 , 100  will continue to cycle back to the decision step  50  at programmed intervals or up receipt of more information by the vehicle ECU or child safety lock ECU until at the decision step  50  it is determined that a crash has occurred. At the decision step  50  a determination is also made as to the type of crash and event and whether or not there should be a delay in taking action. If the system  10 ,  100  determines that a crash has occurred then at step  54  the child safety lock actuator is commanded to disengage. After step  54  the system  10 ,  100  will take no further action until the vehicle has turned off and then will restart the process at step  48  upon starting of the vehicle. 
       FIG. 6  is a decision box diagram showing more details concerning the operational routine of the invention. Upon a vehicle turn on step  58 , vehicle ECU (if present) and the child safety lock ECU at step  60  “ECU init” operates in an initialization mode. At step  62  “Diagnose CSL State” the child safety lock ECU determines that state of the child safety lock actuator, which can be engaged or disengaged. At a decision step  64  the child safety lock ECU waits until a determination is made whether a “crash occurred?” This includes a determination of whether a crash has occurred that warrants unlocking the child safety lock. If at decision step  64  the answer is “YES” then at decision step  66  a determination is made whether “child safety lock locked?” This determination is made by information obtained at step  62  where the child safety lock state is determined, however, the child safety lock ECU may also perform a subsequent diagnosis of the state of the child safety lock. If is determined that the child safety lock is locked then at step  68  the child safety lock will be unlocked and at step  70  operational routine until the vehicle is turned off and then back on. 
     If at decision step  64  it is determined that no crash occurred than at steps  72  the child safety lock ECU will “diagnose the child safety lock” and step  74  will “define child safety lock state” in order to perform a self test or diagnose the child safety lock. This will allow the child safety lock ECU to check or confirm the status of the child safety lock to store in the memory of the child safety lock ECU where the routine will cycle back to decision step  64 . Steps  72 ,  74  will also allow the child safety lock ECU to check for failure of the child safety lock. 
     The description of the invention is merely exemplary in nature and, thus, variations that do not depart from the gist of the invention are intended to be within the scope of the invention. Such variations are not to be regarded as a departure from the spirit and scope of the invention.