Battery change apparatus and method for a locomotive remote control system

Abstract

A remote control system ( 10 ) for a locomotive ( 14 ) having a auxiliary power source ( 42 ) in the operator control unit (OCU) ( 16 ) so that the unique communications link identifier stored in the volatile memory ( 40 ) of the OCU is not lost during change-out of the OCU main battery ( 22 ). A method ( 20 ) for changing the OCU main battery ( 22 ) may include the step of entering a power saving mode ( 54 ) while operating on the auxiliary power source. The locomotive is maintained in a safe condition without unlinking from the OCU for a predetermined time interval ( 66 ) until full power is re-established using the refreshed battery in the OCU. In one embodiment, auxiliary power may be provided by one of two batteries ( 72, 74 ) in the OCU while the other of the two batteries is being changed. A sliding panel ( 78 ) may be used to allow only one battery to be removed from the OCU at a time.

We claim as our invention:  
     
         1 . A method for refreshing a power source in a portable operator control unit (OCU) used for remotely controlling the operation of a locomotive, the method comprising: 
 operating an OCU with a first power source to control a locomotive over a communication link characterized by a unique identifier; and    switching the operation of the OCU from the first power source to a second power source without losing the unique identifier so as to maintain the communication link with the locomotive.    
     
     
         2 . The method of  claim 1 , wherein the step of switching comprises providing power from the second power source to a volatile memory storing the unique identifier so that the volatile memory is not erased while the first power source is being refreshed.  
     
     
         3 . The method of  claim 1 , further comprising providing power from the second power source to a transmitter portion of the OCU while the first power source is being refreshed to allow the transmitter portion to maintain the communication link.  
     
     
         4 . The method of  claim 1 , further comprising sending a signal to the locomotive to put the locomotive in a safe mode prior to the step of switching.  
     
     
         5 . The method of  claim 1 , further comprising providing one of a capacitor, a long-term storage battery, and a solar panel as the second power source.  
     
     
         6 . The method of  claim 1 , wherein the OCU comprises two batteries each capable of powering the OCU, the method further comprising: 
 switching the source of power for the OCU from a first of the batteries to a second of the batteries in response to movement of a mechanism that limits access to only one of the two batteries at a time.    
     
     
         7 . The method of  claim 1 , further comprising: 
 monitoring a condition of the first power sources; and    switching operation of the OCU from the first power source to the second power source when the condition reaches a predetermined level.    
     
     
         8 . The method of  claim 1 , further comprising allowing transmission from the OCU to the locomotive to be suspended for a predetermined time period during the step of switching without interrupting the communication link.  
     
     
         9 . A system for hot-swapping power sources in a locomotive remote control system, wherein a portable operator control unit (OCU) is in communication with a receiver on a locomotive being remotely controlled over a communication link comprising a unique identifier stored in a volatile memory of the OCU, the system comprising: 
 a first power source;    a second power source; and    a circuit for providing power to the OCU from the second power source so that the communication link with the locomotive is maintained while the first power source is being refreshed.    
     
     
         10 . The system of  claim 9 , further comprising a circuit for providing power to a transmitter portion of the OCU from the second power source while the first power source is being refreshed.  
     
     
         11 . The system of  claim 9 , further comprising a circuit for providing power from the second power source to a volatile memory portion of the OCU storing the unique identifier while the first power source is being refreshed.  
     
     
         12 . The system of  claim 9 , wherein the second power source comprises one of a capacitor, a long-term storage battery and a solar panel.  
     
     
         13 . The system of  claim 9 , further comprising: 
 two batteries each capable of powering the OCU; and    a mechanism limiting physical access to only one of the two batteries at a time.    
     
     
         14 . The system of  claim 13 , further comprising a switch responsive to a position of the mechanism for switching the source of power for the OCU from a first of the two batteries to a second of the two batteries.  
     
     
         15 . The system of  claim 13 , wherein the mechanism comprises a sliding panel in a battery compartment of the OCU.  
     
     
         16 . The system of  claim 9 , further comprising a timer circuit for unlinking the communications link if the first power source is not refreshed within a predetermined time period.  
     
     
         17 . The system of  claim 9 , further comprising a failsafe mode preventing inadvertent loss of power to the OCU.  
     
     
         18 . A remote control system for controlling a locomotive comprising: 
 a controller onboard a locomotive for controlling the locomotive in response to a remote control signal comprising a unique identifier;    an operator control unit (OCU) remote from the locomotive for generating the remote control signal, wherein the OCU further comprises: 
 a first power source;  
 a second power source; and  
 a circuit for providing power to a volatile memory portion of the OCU from the second power source to maintain the unique identifier in the volatile memory while the first power source is being refreshed.  
   
     
     
         19 . The system of  claim 18 , wherein the second power source comprises one of a capacitor, a long-term storage battery and a solar panel.  
     
     
         20 . The system of  claim 18 , further comprising: 
 a first battery;    a second battery;    a mechanism providing access to only one of the first battery and the second battery at a time; and    a switch responsive to a position of the mechanism for switching power for the OCU from the first battery to the second battery.