Cylinder apparatus with a capability of detecting piston position in a cylinder

Abstract

A cylinder apparatus with a capability of detecting a piston position includes a cylinder, a throttling valve, a positive limit and a pressure switch. A piston is movably mounted in the cylinder. A piston rod with an outside end protruding out of the cylinder is attached to the piston and adapted to push an object. The cylinder is connected to a pump with pipes. The throttling valve and the pressure switch are connected to the pipes, and the pressure switch is installed between the cylinder and the throttling valve. Consequently, when the pump starts pumping, the piston rod pushes the object to abut the positive limit. The stopped movement of the piston rod will change the pressure in the cylinder that triggers the pressure switch to send a signal to a controlling host to stop the pump.

1 . A cylinder apparatus with a capability of detecting piston position in a cylinder of a cylinder and the cylinder apparatus comprising: 
 a cylinder having 
 a closed tubular housing with a chamber defined in the closed tubular housing and adapted to connect to a pump with pipes;  
 a piston movably mounted in the chamber in the closed tubular housing and splitting the chamber into a retracting chamber and a protruding chamber; and  
 an actuating device coupled to the piston and adapted to selectively push and carry an object;  
   a positive limit positioned corresponding to the actuating device adapted to stop movement of the actuating device; 
 a first throttling valve selectively connected to the pipes between one of the retracting and the protruding chambers and the pump; and  
 a first pressure switch connected to the pipes between the first throttling valve and the chamber.  
   
   
   
       2 . The cylinder apparatus as claimed in  claim 1 , wherein 
 the actuating device is a piston rod with an inside end and an outside end, the inside end of the piston rod attached to the piston in the closed tubular housing and the outside end of the piston rod extending out of the closed tubular housing and adapted to push the object to abut the positive limit.    
   
   
       3 . The cylinder apparatus as claimed in  claim 2 , wherein 
 the first throttling valve is connected to the pipes between the retracting chamber in the closed tubular housing and the pump, and    the first pressure switch is connected to the pipes between the retracting chamber in the closed tubular housing and the first throttling valve.    
   
   
       4 . The cylinder apparatus as claimed in  claim 2 , wherein 
 the first throttling valve is connected to the pipes between the protruding chamber in the closed tubular housing and the pump, and    the first pressure switch is connected to the pipes between the protruding chamber in the closed tubular housing and the first throttling valve.    
   
   
       5 . The cylinder apparatus as claimed in  claim 4 , wherein 
 the cylinder apparatus further comprises 
 a second throttling valve connected to the pipes between the retracting chamber in the closed tubular housing and the pump, and  
 a second pressure switch connected to the pipes between the retracting chamber in the closed tubular housing and the second throttling valve.  
   
   
   
       6 . The cylinder apparatus as claimed in  claim 3 , wherein the first throttling valve is one-directional.  
   
   
       7 . The cylinder apparatus as claimed in  claim 4 , wherein the first throttling valve is one-directional.  
   
   
       8 . The cylinder apparatus as claimed in  claim 5 , wherein both the first and the second throttling valves are one-directional.