Lubricant-Free Compressor Having a Graphite Piston in a Glass Cylinder

Abstract

A substantially lubricant-free compressor comprising a glass cylinder having a hollow interior, a graphite piston within the glass cylinder, a connecting rod operably attached to the graphite piston, a cylinder head sealing one end of the glass cylinder, an exhaust valve in operable connection with the hollow interior of the glass cylinder, and an inlet valve in operable connection with the hollow interior of the glass cylinder. The compressor may be driven by any suitable means including without limitation a brushless DC motor or a smart material actuator.

1 . A compressor comprising
 a glass cylinder having a hollow interior,   a graphite piston within the glass cylinder,   a connecting rod operably attached to the graphite piston,   a cylinder head sealing one end of the glass cylinder and comprising an exhaust valve in operable connection with the hollow interior of the glass cylinder, and   an inlet valve in operable connection with the hollow interior of the glass cylinder,   
       wherein upon the connecting rod moving the graphite piston toward the cylinder head, material within the hollow interior of the glass cylinder is compressed until a sufficient pressure is attained to expel a portion of the material out the exhaust valve, and upon the connecting rod moving the graphite piston away from the cylinder head, material is drawn into the hollow interior of the glass cylinder through the inlet valve. 
     
     
         2 . The compressor of  claim 1  wherein the inlet valve is mounted in the cylinder head. 
     
     
         3 . The compressor  claim 1  further comprising a piston T-nut adapted to retain the graphite piston to the connecting rod. 
     
     
         4 . The compressor  claim 3  wherein the inlet valve is mounted to the piston T-nut. 
     
     
         5 . The compressor of  claim 1  wherein the inlet valve mounted to the graphite piston. 
     
     
         6 . The compressor of  claim 1  further comprising a motor operably connected to the connecting rod such that operation of the motor causes the connecting rod to move the graphite piston transversely in the glass cylinder. 
     
     
         7 . The compressor of  claim 1  further comprising an actuator operably connected to the connecting rod such that operation of the actuator causes the connecting rod to move the graphite piston transversely in the glass cylinder. 
     
     
         8 . The compressor of  claim 1 , further comprising a means of generating transverse motion of the graphite piston, wherein the motion generating means is operably attached to the connecting rod. 
     
     
         9 . The compressor of  claim 8 , wherein the motion generating means is a motor operably attached to an eccentric operably attached to the connecting rod 
     
     
         10 . The compressor of  claim 9  wherein the motor is a brushless DC motor. 
     
     
         11 . The compressor of  claim 8 , wherein the motion generating means is a smart material actuator operably attached to the connecting rod whereby repeated activation of the actuator urges the piston in a first direction within the glass cylinder and deactivation of the actuator urges the piston in a second direction substantially opposite to the first direction within the glass cylinder. 
     
     
         12 . The compressor of  claim 11  further comprising an electronic control circuit adapted to operate the smart material actuator at a resonant frequency. 
     
     
         13 . The compressor of  claim 1 , further comprising a low-friction ring adapted to mount on the graphite piston, whereby the ring provides a low-friction seal between the graphite piston and the inner walls of the glass cylinder. 
     
     
         14 . The compressor of  claim 13 , wherein the low-friction ring is formed of a synthetic resin. 
     
     
         15 . The compressor of  claim 1  wherein the outside diameter of the graphite piston is substantially equal to the inside diameter of the glass cylinder. 
     
     
         16 . The compressor of  claim 1 , wherein the glass cylinder is formed of borosilicate glass. 
     
     
         17 . The compressor of  claim 2  wherein the cylinder head further comprises a second inlet valve in operable connection with the hollow interior of the glass cylinder. 
     
     
         18 . The compressor of  claim 1  in which the cylinder head further comprises a second exhaust valve in operable connection with the hollow interior of the glass cylinder. 
     
     
         19 . The compressor  claim 1  wherein the inlet valve is a first reed valve and the exhaust valve is a second reed valve. 
     
     
         20 . A compressor comprising
 a glass cylinder having a hollow interior,   a graphite piston within the glass cylinder,   a connecting rod operably attached to the graphite piston,   a cylinder head sealing one end of the glass cylinder and comprising an exhaust port in operable connection with the hollow interior of the glass cylinder,   an inlet port in operable connection with the hollow interior of the glass cylinder,   at least one inlet valve in operable connection with the inlet port, and   at least one exhaust valve in operable connection with the outlet port,   
       wherein upon the connecting rod moving the graphite piston toward the cylinder head, material within the hollow interior of the glass cylinder is compressed until a sufficient pressure is attained to expel a portion of the material out the exhaust valve, and upon the connecting rod moving the graphite piston away from the cylinder head, material is drawn into the hollow interior of the glass cylinder through the inlet valve.