Temperature compensated fluid sensor

Claim 2

In a sensor device comprising a housing member defining a chamber, a thermally conductive member within said chamber, a tip member secured to said housing and forming a closure for said chamber, an element within said chamber having first and second spaced apart portions, said first portion being joined in heat conductive relationship to said thermally conductive member, said second portion being secured iN thermally conductive relationship to a surface of the tip member within said chamber, means for heating said element comprising an electrical resistive element, and first and second heat responsive members secured to said first and second spaced apart portions, respectively, said heat responsive members each having a free end adapted for engaging only when the temperature difference between said first and second portions of said element exceeds a predetermined level, the improvement comprising: providing a portion of electrically insulative material intermediate and engaging said first and second spaced apart portions whereby said first spaced apart portion is electrically insulated from said electrical resistive element and said second spaced apart portion is electrically connected to said electrical resistive element.

Claim 3

The improvement according to claim 1 wherein said portion of electrically insulative material intermediate and engaging said first and second spaced apart portions is glass.

Claim 4

The improvement according to claim 1 wherein said thermally conductive member and said tip member are electrically conductive.

Claim 5

The improvement according to claim 1 wherein said heat responsive members are bimetallic members.

Claim 6

In a sensing apparatus comprising a sensor device comprising a housing member defining a chamber, a thermally conductive member within said chamber, a tip member secured to said housing and forming a closure for said chamber, an element within said chamber having first and second spaced apart portions, said first portion being joined in heat conductive relationship to said thermally conductive member, said second portion being secured in thermally conductive relationship to a surface of the tip member within said chamber, means for heating said element comprising an electrical resistive element, first and second heat responsive members secured to said first and second spaced apart portions, respectively, said heat responsive members each having a free end adapted for engaging only when the temperature difference between said first and second portions of said element exceeds a predetermined level, and means for sensing when said heat responsive members are engaged, the improvement comprising: providing a portion of electrically insulative material intermediate and engaging said first and second spaced apart portions whereby said first spaced apart portion is electrically insulated from said electrical resistive element and said second spaced apart portion is electrically connected to said electrical resistive element.

Claim 7

In a sensing apparatus comprising a sensor device comprising a housing member defining a chamber, a thermally conductive member within said chamber, a tip member secured to said housing and forming a closure for said chamber, an element within said chamber having first and second spaced apart portions, said first portion being joined in heat conductive relationship to said thermally conductive member, said second portion being secured in thermally conductive relationship to a surface of the tip member within said chamber, means for heating said element comprising an electrical resistive element, first and second heat responsive members secured to said first and second spaced apart portions, respectively, said heat responsive members each having a free end adapted for engaging only when the temperature difference between said first and second portions of said element exceeds a predetermined level, and means for sensing when said heat responsive members are engaged, the improvement comprising: providing a portion of electrically insulative material intermediate and engaging said first and second spaced apart portions whereby said first spaced apart portion is electrically insulated from said electrical resistive element and said second spaced apart portion is electrically connected to said electrical resistive element.

Claim 8

The improvement according to claim 5 wherein said portion of electrically insulative material intermediate and engaging said first and second spaced apart portions is glass.

Claim 9

The improvement according to claim 5 wherein said means for sensing when said heat responsive members are engaged is an electrical circuit comprising a source of electrical potential operatively connected to said heat responsive members for opening and closing said circuit and a current indicating means adapted for indicating electrical current in said circuit when said heat responsive members are engaged.

Claim 10

The improvement according to claim 5 wherein said heat responsive members are bimetallic members.

Claim 11

The improvement according to claim 7 wherein said electrical resistive element within said chamber is operatively connected to said source of electrical potential.

Claim 12

The improvement according to claim 7 wherein said thermally conductive member is electrically conductive and is operatively connected to said source of electrical potential and said tip member is electrically conductive and is operatively connected to said source of electrical potential and said electrical resistive element.

Claim 13

In the combination comprising a container having walls adapted for containing a fluid therein, a sensor device at least partially positioned within a wall of said container, said device comprising a housing member defining a chamber, a thermally conductive member within said chamber, a tip member secured to said housing and forming a closure for said chamber, an element within said chamber having first and second spaced apart portions, said first portion being joined in heat conductive relationship to said thermally conductive member and said second portion being secured in thermally conductive relationship to a surface of the tip member within said chamber, means for heating said element comprising an electrical resistive element, first and second heat responsive members secured to said first and second spaced apart portions, respectively, said heat responsive members each having a free end adapted for engaging only when the temperature difference between said first and second portions of said element exceeds a predetermined level, and means for sensing when said heat responsive members are engaged, the improvement comprising: providing a portion of electrically insulative material intermediate and engaging said first and second spaced apart portions whereby said first spaced apart portion is electrically insulated from said electrical resistive element and said second spaced apart portion is electrically connected to said electrical resistive element.

Claim 14

In the combination comprising a container having walls adapted for containing a fluid therein, a sensor device at least partially positioned within a wall of said container, said device comprising a housing member defining a chamber, a thermally conductive member within said chamber, a tip member secured to said housing and forming a closure for said chamber, an element within said chamber having first and second spaced apart portions, said first portion being joined in heat conductive relationship to said thermally conductive member and said second portion being secured in thermally conductive relationship to a surface of the tip member within said chamber, means for heating said element comprising an electrical resistive element, first and second heat responsive members secured to said first and second spaced apart portions, respectively, said heat responsive members each having a free end adapted for engaging only when the temperature difference between said first and second portions of said element exceeds a predetermined level, and means for sensing when said heat responsive members are engaged, the improvement comprising: providing a portion of electrically insulative material intermediate and engaging said first and second spaced apart portions whereby said first spaced apart portion is electrically insulated from said electrical resistive element and said second spaced apart portion is electrically connected to said electrical resistive element.

Claim 15

The improvement according to claim 11 wherein said means for sensing when said heat responsive members are engaged is an electrical circuit comprising a source of electrical potential operatively connected to said heat responsive members for opening and closing said circuit and a current indicating means adapted for indicating electrical current in said circuit when said heat responsive members are engaged.

Claim 16

The improvement according to claim 11 wherein said portion of electrically insulative material intermediate and engaging said first and second spaced apart portions is glass.

Claim 17

The improvement according to claim 11 wherein said heat responsive members are bimetallic members.

Claim 18

The improvement according to claim 12 wherein said electrical resistive element within said chamber is operatively connected to said source of electrical potential.

Claim 19

The improvement according to claim 12 wherein said thermally conductive member is electrically conductive and is operatively connected to said source of electrical potential and said tip member is electrically conductive and is operatively connected to said source of electrical potential and said electrical resistive element.