System for monitoring and / or controlling equipment in a hazardous area

Abstract

A system for monitoring and/or controlling equipment in a hazardous area can include at least one sensor disposed within the hazardous area. Each sensor can be non-electrical and can be adapted to interact with the equipment and generate at least a first sensor output and second sensor output. The first sensor output can be indicative of a first equipment state and a second sensor output can be indicative of a second equipment state. The system can also include at least one converter disposed outside the hazardous area. Each converter can be in communication with at least one of the sensors. Each converter can be configured to receive the first and second sensor output and generate a converter output signal based on at least one of the first and second sensor outputs.

1 . A system for monitoring or controlling equipment in a hazardous area, the system comprising:
 at least one sensor disposed within a hazardous area, each sensor being non-electrical and being adapted to interact with the equipment and generate at least a first non-electric sensor output and a second non-electric second sensor output, the first sensor output being indicative of a first equipment state and the second sensor output being indicative of a second equipment state;   a non-electrical communication link extending from the at least one sensor across a boundary between the hazardous area and a non-hazardous area, the non-electric communication link to carry the sensor outputs from the at least one sensor; and   at least one controller disposed in the non-hazardous area, the at least one controller coupled to the communication link and operable to generate a controller output signal based on the sensor outputs.   
     
     
         2 . The system of  claim 1 , further comprising at least one converter communicably linking the at least one sensor and the controller, the at least one converter connected to the communication link to receive the sensor outputs and convert it to a form useable by the at least one controller. 
     
     
         3 . The system of  claim 2 , wherein the at least one converter is part of the at least one controller and converts the sensor outputs within the controller. 
     
     
         4 . The system of  claim 2 , wherein the at least one converter is disposed in the non-hazardous area between the at least one sensor and the at least one controller. 
     
     
         5 . The system of  claim 2 , wherein the at least one converter converts the non-electric sensor outputs to electrical signals. 
     
     
         6 . The system of  claim 2 , wherein the controller is adapted to control the state of equipment based on the converter output signal. 
     
     
         7 . The system of  claim 1 , wherein the sensor outputs comprise optical signals. 
     
     
         8 - 11 . (canceled) 
     
     
         12 . The system of  claim 1 , further comprising at least one trigger member mounted on the equipment, each trigger member corresponding to and adapted to engage at least one valve, each trigger member and corresponding valve connected to the equipment so that changing the equipment from the first equipment state to the second equipment state causes the trigger member to change the configuration of at least one corresponding valve. 
     
     
         13 . The system of  claim 12 , wherein each trigger member comprises a cam and each valve comprises a complimentary cam follower configured to engage the at least one cam. 
     
     
         14 . A lift system for operation in a hazardous area, the lift system comprising:
 a) a lift mechanism, the lift mechanism being movable between first and second positions;   b) at least one sensor connected to the lift, the at least one sensor being non-electric and being configured to generate at least a first non-electric sensor output and second non-electric sensor output, the first sensor output being indicative of the lift mechanism being in the first position and the second sensor output being indicative of the lift mechanism being in the second position; and   c) a controller disposed outside the hazardous area, the controller in communication with the at least one sensor, and the controller being adapted to control the movement of the equipment based on the sensor outputs.   
     
     
         15 . The lift of  claim 14 , further comprising at least one convener communicably linking the at least one sensor and the controller the at least one converter to receive the sensor outputs and convert it to a form useable by the at least one controller. 
     
     
         16 - 17 . (canceled) 
     
     
         18 . The lift of  claim 15 , wherein the at least one converter converts the non-electric sensor outputs to electrical signals, and the controller is adapted to control the state of equipment based on the converter output signal. 
     
     
         19 . (canceled) 
     
     
         20 . The lift of  claim 14 , wherein the sensor outputs comprise optical signals. 
     
     
         21 - 26 . (canceled) 
     
     
         27 . The lift of  claim 14 , wherein the at least one sensor comprises at least a first sensor and a second sensor, the first sensor interacting with the lift so that the first sensor is triggered when the lift mechanism is in the first position, the second sensor interacting with the lift so that the second sensor is triggered when the lift mechanism is in the second position. 
     
     
         28 - 29 . (canceled) 
     
     
         30 . A method of monitoring and/or controlling equipment in a hazardous area, the method comprising the steps of:
 a) sensing an equipment state using at least one sensor within the hazardous area, the at least one sensor being non-electric and being adapted to interact with the equipment;   generating at least a first non-electric sensor output and a second non-electric sensor output, the first sensor output being indicative of a first equipment state and a second sensor output being indicative of a second equipment state;   c) transmitting to a controller the non-electric sensor outputs across a boundary between the hazardous area and a non-hazardous area;   d) generating a controller output signal based on the sensor outputs; and   e) monitoring and/or controlling the equipment based on the controller output signal.   
     
     
         31 . The method of  claim 30 , further comprising converting in the non-hazardous area the non-electric sensor outputs to at least one corresponding signal for use by the controller. 
     
     
         32 - 33 . (canceled) 
     
     
         34 . The method of  claim 30 , wherein the at least one converter converts the non-electric sensor outputs to electrical signals. 
     
     
         35 . The method of  claim 30 , wherein the non-electric sensor outputs comprise optical signals. 
     
     
         36 . (canceled) 
     
     
         37 . The method of  claim 30 , wherein the equipment state is at least first and second positions in a lift mechanism. 
     
     
         38 . (canceled) 
     
     
         39 . The method of  claim 37 , wherein the lift mechanism comprises first and second scissor lifts, and the controller output signal is used to equalize the positions of the first and second scissor lifts.