Electromagnetically transparent fluidic operators for remote operation of electric switches and method of adapting electric switches for remote, fluidic operation

Abstract

An electromagnetically transparent fluidic operator for adapting a conventional, mechanically operated electric switch to remote, fluidic operation includes a non-metallic housing for being rigidly attached to the electric switch with a chamber in the housing aligned with a mechanical actuator of the electric switch and a non-metallic, expandable reservoir mounted by the housing. The reservoir includes a nipple rigidly attached to the housing and a deformable diaphragm forming a seal with the nipple and being disposed in the chamber close to the mechanical actuator. The reservoir is pressurized with fluid from a remote location causing the diaphragm to deform and the reservoir to expand thereby applying a positive pressure or operating force against the mechanical actuator to operate the electric switch. A method of adapting an electric switch for remote, fluidic operation includes the steps of rigidly attaching the housing to a selected electric switch such that the chamber in the housing is aligned with the mechanical actuator, positioning the diaphragm in the chamber close to the mechanical actuator, rigidly attaching the nipple to the housing, establishing a seal between the nipple and the diaphragm to form a fluid-tight reservoir and supplying fluid to the reservoir to deform the diaphragm and apply the operating force against the mechanical actuator.

What is claimed is: 
     
       1. An electromagnetically transparent fluidic operator for attachment to an electric switch for operating the electric switch remotely, the electric switch having a switch housing and a mechanical actuator for operating the electric switch in response to an operating force applied against the mechanical actuator, said fluidic operator comprising: a fluidic housing made of non-metallic material for being rigidly mounted to the electric switch and having a chamber therein aligned with the mechanical actuator when said fluidic housing is mounted to the switch housing; and   an expandable reservoir made of non-metallic material rigidly mounted to said fluidic housing and including a nipple rigidly attached to said fluidic housing and a deformable diaphragm forming a seal with said nipple, said diaphragm being arranged in said chamber to be disposed close to the mechanical actuator, said nipple having an opening therein for receiving fluid from a remote location to deform said diaphragm, said diaphragm being confined by said fluidic housing such that said deformed diaphragm applies the operating force.   
     
     
       2. An electromagnetically transparent fluidic operator as recited in claim 1 wherein said fluidic housing has a passage therein for receiving the electric switch. 
     
     
       3. An electromagnetically transparent fluidic operator as recited in claim 2 wherein said diaphragm has a closed end disposed adjacent the mechanical actuator and an open end having a peripheral edge forming said seal with said nipple. 
     
     
       4. An electromagnetically transparent fluidic operator as recited in claim 3 wherein said diaphragm is confined by said fluidic housing to cause said reservoir to expand in the direction of movement of the mechanical actuator. 
     
     
       5. An electromagnetically transparent fluidic operator as recited in claim 4 and further including a non-metallic pressure plate disposed in said chamber between said diaphragm and the mechanical actuator. 
     
     
       6. An electromagnetically transparent fluidic operator as recited in claim 1 wherein said nipple is threadedly attached to said fluidic housing. 
     
     
       7. An electromagnetically transparent fluidic operator as recited in claim 1 wherein said fluidic housing comprises a first tubular member and said nipple comprises a second tubular member pressed into said first tubular member. 
     
     
       8. An electromagnetically transparent fluidic operator as recited in claim 7 wherein said first and second tubular members are made of polyvinylchloride. 
     
     
       9. An electromagnetically transparent fluidic operator as recited in claim 1 wherein said diaphragm is made of latex rubber. 
     
     
       10. An electromagnetically transparent fluidic operator as recited in claim 1 wherein said fluidic operator is electromagnetically transparent at radio frequencies. 
     
     
       11. An electromagnetically transparent fluidic operator as recited in claim 10 wherein said fluidic operator is electromagnetically translucent at microwave frequencies. 
     
     
       12. An electromagnetically transparent fluidic operator as recited in claim 1 and further including an adjustment mechanism disposed in said fluidic housing for selectively adjusting the operating force required to be applied by said diaphragm against the mechanical actuator to operate the electric switch. 
     
     
       13. A remotely operable electric switch assembly comprising: an electric switch having a switch housing and a mechanical actuator protruding from said switch housing and being movable relative to said switch housing to operate said electric switch; and   an electromagnetically transparent fluidic operator attached to said electric switch for operating said electric switch remotely, said fluidic operator including a fluidic housing attached to said switch housing, expandable reservoir disposed in said fluidic housing and a source of fluid coupled with said reservoir for pressurizing said reservoir from a remote location, said reservoir including a nipple rigidly attached to said fluidic housing and a deformable diaphragm disposed adjacent said mechanical actuator and having a peripheral edge forming a seal with said nipple, said diaphragm being deformable to cause said reservoir to expand in response to pressurization of said reservoir with said fluid, said reservoir being confined by said fluidic housing to expand in the direction of movement of said mechanical actuator to move said mechanical actuator to open said electric switch.   
     
     
       14. A remotely operable electric switch assembly as recited in claim 13 wherein said electric switch is a momentary pushbutton electric microswitch and said mechanical actuator is a pushbutton. 
     
     
       15. A remotely operable electric switch assembly as recited in claim 14 and further including a pressure plate interposed between said diaphragm and said pushbutton. 
     
     
       16. A remotely operable electric switch assembly as recited in claim 15 and further including a spring mounted in compression between said pressure plate and said switch for selectively adjusting the pressure required in said reservoir to move said mechanical actuator. 
     
     
       17. A method of adapting an electric switch for fluidic, remote operation comprising the steps of: selecting an electric switch to be adapted for remote operation, the switch having a switch housing and a mechanical actuator for operating the electric switch in response to an operating force applied against the mechanical actuator; and   attaching an electromagnetically transparent fluidic operator to the electric switch, the attacthing step including   rigidly attaching a non-metallic housing to the electric switch such that a chamber in the non-metallic housing is aligned with the mechanical actuator;   positioning a non-metallic, stretchable diaphragm in the chamber close to the mechanical actuator;   rigidly attaching a non-metallic nipple to the non-metallic housing;   establishing a seal between the nipple and the diaphragm to form a fluid-tight reservoir; and   supplying fluid to the reservoir from a remote location to stretch the diaphragm and pressurize the reservoir to apply an operating force against the mechanical actuator to operate the electric switch.   
     
     
       18. A method of adapting an electric switch for fluidic, remote operation as recited in claim 17 and further including the step of positioning a non-metallic pressure plate between the diaphragm and the mechanical actuator such that the diaphragm applies pressure against the pressure plate and the pressure plate applies pressure against the mechanical actuator to operate the electric switch. 
     
     
       19. A method of adapting an electric switch for fluidic, remote operation as recited in claim 18 and further including the step of positioning a non-metallic spring between the pressure plate and the electric switch to adjust the fluidic pressure required in the reservoir to operate the electric switch.