Pop-up temperature indicator for use in a 3-CD type air compressor or similar device

A method for visually indicating when a specified temperature has been exceeded in a fluid flow through a conduit of a two-stage air compressor, wherein said air compressor includes at least one low pressure cylinder for receiving air at an ambient atmospheric pressure and for compressing such air to a first elevated pressure, a high pressure cylinder for receiving such air at such first elevated pressure and for compressing such air at such first elevated pressure to a second elevated pressure substantially higher than said first elevated pressure, and a conduit for supplying such air at said first elevated pressure to said high pressure cylinder, said method comprising the steps of:

• mounting a temperature indicator in said conduit such that said temperature indicator projects through said conduit and into said fluid flow in said conduit;
• said temperature indicator comprising:
• a housing, said housing substantially enclosing an internal chamber and said housing having a bore extending from said internal chamber to an external surface of said housing;
• an indicator member disposed, at least in part, within said internal chamber of said housing, said indicator member extending from said internal chamber and into said bore;
• a biasing element disposed within said internal chamber and exerting a biasing force between said housing and said indicator member and urging said indicator member toward said bore;
• and
• a bonding agent forming a bond between said indicator member and said housing to thereby restrain said indicator member from movement toward said bore under action of said biasing element, said bonding agent being thermosensitive to substantially release said bond between said indicator member and said housing when a temperature of said bonding agent substantially reaches said specified temperature;
• said bonding agent being disposed on said temperature indicator such that said bonding agent is placed in substantially direct contact with said fluid flow in said conduit when said temperature indicator is mounted in said conduit such that said temperature indicator projects through said conduit and into said fluid flow in said conduit.

A method for visually indicating when a specified temperature has been exceeded in a fluid flow through a conduit, said method comprising the steps of:

• providing an aperture in said conduit;
• mounting a temperature indicator assembly in such aperture such that said temperature indicator assembly projects through such aperture and into such fluid flow in such conduit;
• said temperature indicator assembly comprising:
• a cartridge holder for engagement with such aperture in such conduit, said cartridge holder having a concavity formed therein;
• a bore extending from said concavity to an external surface of said cartridge holder;
• and
• a cartridge for attachment to said cartridge holder, said cartridge including:
• a base member;
• a cylinder portion extending outwardly from said base member;
• an indicator member, said indicator member including a piston portion and a stem portion extending outwardly from said piston portion, said piston portion of said indicator member and said cylinder portion being slidingly mated for coaxial movement therebetween;
• a biasing element disposed between said piston portion and said base member and urging said piston portion away from said base member;
• and
• a bonding agent forming a bond between said indicator member and said cylinder portion to thereby restrain said indicator member from movement away from said base member under action of said biasing element, said bonding agent being thermosensitive to substantially release said bond between said indicator member and said cylinder portion when a temperature of said bonding agent substantially teaches said specified temperature;
• said temperature indicator assembly additionally including an attachment apparatus for releasably attaching said cartridge to said cartridge holder to thereby form an assembled structure, said stem portion of said indicator member extending into said bore in said assembled structure.