Patent CA1109908A successfully refreshed from Google Patents.
CA1109908A
Expired / Lapsed
CA
⏱️ 0.0 years remaining
Thermal switch with organic glass bead mixture fusible pellet
Assignee: Illinois Tool Works Inc
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Filing: 1979-08-20
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Granted: 1981-09-29
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Expires: 1999-08-20
Abstract
Abstract THERMAL SWITCH WITH ORGANIC GLASS BEAD MIXTURE FUSIBLE PELLET Abstract of the Disclosure A thermal switch for automatically opening a circuit when the ambient temperature exceeds a predetermined level is disclosed which utilizes a fusible pellet formed of an organic-glass bead mixture. The organic-glass bead pellet retains a pair of leads in contact with each other when the ambient temperature is below the melting temperature of the organic material. The addition of the glass beads to the tem-perature sensing pellet allows the compressive strength that is needed to hold the leads together to be more reliably controlled. In the process of combining the organic material and the glass beads, to form the pellet, the organic material is first melted so as to flow around the beads. Manufacture of the thermally-fusible pellet in this manner eliminates the voids which occur in the pressed organic pellets that are conventionally used in thermal sensing devices. The elimination of these voids increases the strength of the otherwise relatively fragile pellet thereby improving reliability of thermal switches which utilize the improved pellet of the present invention.
Inventors
- 👤 John K. Mcvey
- 👤 Bruce A. Luxon
Bibliographic Details
Application Number
—
Jurisdiction
CA
Data Source
google_patents
Last Synchronized
2026-11-03 10:33
CPC Classifications
H; H01; H01H; H01H37/00; H01H37/74; H01H37/76; H01H37/764; B; B29; B29C; B29C43/00; B29C43/003; B29C43/02; B29C43/18; B29K; B29K2103/00; B29K2103/04; B29K2709/00; B29K2709/08; B29L; B29L2031/00; B29L2031/34; B29L2031/3443; H01H2037/769
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
82 words
In a thermal switch comprising a housing, a pair of electrical leads in said housing, contact means on said leads for forming a circuit connection between said electrical leads and a thermally-fusible pellet for controlling said contact means, the improvement wherein said thermally-fusible pellet is formed of a multitude of solid insulating particles that are surrounded and held in a unified mass by a fusible material that melts at a predetermined temperature while said insulating particles remain solid at said predetermined temperature.
Claim 2
Dependent Claim
82 words
In a thermal switch comprising a housing, a pair of electrical leads in said housing, contact means on said leads for forming a circuit connection between said electrical leads and a thermally-fusible pellet for controlling said contact means, the improvement wherein said thermally-fusible pellet is formed of a multitude of solid insulating particles that are surrounded and held in a unified mass by a fusible material that melts at a predetermined temperature while said insulating particles remain solid at said predetermined temperature.
Claim 3
Dependent Claim
45 words
A thermal switch as claimed in Claim 1 wherein said fusible material is an organic material and said insulating particles are comprised of a multitude of spherical-shaped insulating beads in which the volume of the insulating beads substantially exceeds the volume of the fusible material.
Claim 4
Dependent Claim
16 words
A thermal switch as claimed in Claim 1 wherein said fusible material is an organic material.
Claim 5
Dependent Claim
24 words
A thermal switch as claimed in Claim 1 or Claim 3 wherein said insulating particles are comprised of a multitude of spherically-shaped insulating balls.
Claim 6
Dependent Claim
37 words
A thermal switch as claimed in Claim 1 wherein said leads are formed so that said contact means on said leads consist of a ball configuration on one lead and a mating socket configuration on the other.
Claim 7
Dependent Claim
37 words
A thermal switch as claimed in Claim 2 wherein said leads are formed so that said contact means on said leads consist of a ball configuration on one lead and a mating socket configuration on the other.
Claim 8
Dependent Claim
109 words
In a thermal switch as claimed in Claim 5 or Claim 6 the further improvement wherein said housing is generally cylindri-cal in shape, and said thermally-fusible pellet is generally cylin-drical in shape and fits into said housing so that the outer periphery of said thermally-fusible pellet engages the inner periphery of said housing and said thermally-fusible pellet has a central bore in it which receives said contact means on said leads therein and holds said contact means in a normally closed position, and said leads are formed to spring apart upon the melting of said fusible material in said thermally-fusible pellet so as to thereby separate said contact means.
Claim 9
Dependent Claim
137 words
A thermal switch comprising an insulating housing, a pair of electrical leads that extend into said housing and that project therefrom comprising contact portions formed on said leads and located in said housing for forming a circuit connection between said leads and spring portions formed on said leads that are constructed so that said contact portions of said leads tend to spring apart and a thermally-fusible element that engages and holds said contact portions of said leads together against the spring forces developed by said spring portions as long as the ambient temperature remains below a predetermined temperature, said thermally-fusible element comprising a multitude of solid insulating particles that are surrounded and held in a unified mass by a fusible material that melts at said predetermined temperature while said insulating particles remain solid at said predetermined temperature.
Claim 10
Dependent Claim
137 words
A thermal switch comprising an insulating housing, a pair of electrical leads that extend into said housing and that project therefrom comprising contact portions formed on said leads and located in said housing for forming a circuit connection between said leads and spring portions formed on said leads that are constructed so that said contact portions of said leads tend to spring apart and a thermally-fusible element that engages and holds said contact portions of said leads together against the spring forces developed by said spring portions as long as the ambient temperature remains below a predetermined temperature, said thermally-fusible element comprising a multitude of solid insulating particles that are surrounded and held in a unified mass by a fusible material that melts at said predetermined temperature while said insulating particles remain solid at said predetermined temperature.
Claim 11
Dependent Claim
45 words
A thermal switch as claimed in Claim 8 wherein said fusible material is an organic material and said insulating particles are comprised of a multitude of spherical-shaped insul-ating beads in which the volume of the insulating beads sub-stantially exceeds the volume of the fusible material.
Claim 12
Dependent Claim
16 words
A thermal switch as claimed in Claim 8 wherein said fusible material is an organic material.
Claim 13
Dependent Claim
21 words
A thermal switch as claimed in Claim 8 wherein said insulating particles are comprised of a multitude of spherically-shaped insulating balls.
Claim 14
Dependent Claim
41 words
A thermal switch as claimed in Claim 8, Claim 9 or Claim 10 wherein said contact portions on said leads consist of a ball configuration on one of said leads and a mating socket configuration on the other of said leads.
Claim 15
Independent Claim
160 words
A method of constructing a thermal switch comprising positioning and insulating housing having a sealed bottom and an open top in a vertical position, dispensing a multitude of solid, insulating particles into the bottom of said housing, disposing a thermally-fusible pill, which melts at a substantially lower temperature than said insulating particles, on top of said insulating particles, heating said pill so that the fusible material of said pill melts and flows around said insulating particles, inserting a core pin into said mixture of melted fusible material and unmelted insulating particles so as to form a core hole therein upon solidification of said fusible material around said insulating particles and removal of said core pin from said housing and inserting contact portions of a pair of leads into said core hole so that said solidified mass of fusible material and insulating particles will hold said contact portions together in a closed circuit configuration until said fusible material is again melted.
Claim 16
Independent Claim
160 words
A method of constructing a thermal switch comprising positioning and insulating housing having a sealed bottom and an open top in a vertical position, dispensing a multitude of solid, insulating particles into the bottom of said housing, disposing a thermally-fusible pill, which melts at a substantially lower temperature than said insulating particles, on top of said insulating particles, heating said pill so that the fusible material of said pill melts and flows around said insulating particles, inserting a core pin into said mixture of melted fusible material and unmelted insulating particles so as to form a core hole therein upon solidification of said fusible material around said insulating particles and removal of said core pin from said housing and inserting contact portions of a pair of leads into said core hole so that said solidified mass of fusible material and insulating particles will hold said contact portions together in a closed circuit configuration until said fusible material is again melted.
Claim 17
Dependent Claim
31 words
A method as claimed in Claim 13 wherein said insulating particles are constructed of a good heat conducting material and are heated at the same time said fusible material is heated.
Claim 18
Independent Claim
118 words
A method of forming a thermally-fusible element for use in thermal switch devices comprising disposing a fusible material in solid form above a multitude of solid particles in a container, wherein said particles melt at a substantially higher temperature than said fusible material, heating said fusible material so that said fusible material flows dawn over said particles to form a mixture of said fusible material and said particles in said container, inserting a core pin into said mixture while said fusible material in said mixture is still a fluid and removing said core pin upon solidification of said fusible material so as to form a core hole in the solidified mass of said fusible material said said particles.
Claim 19
Independent Claim
118 words
A method of forming a thermally-fusible element for use in thermal switch devices comprising disposing a fusible material in solid form above a multitude of solid particles in a container, wherein said particles melt at a substantially higher temperature than said fusible material, heating said fusible material so that said fusible material flows dawn over said particles to form a mixture of said fusible material and said particles in said container, inserting a core pin into said mixture while said fusible material in said mixture is still a fluid and removing said core pin upon solidification of said fusible material so as to form a core hole in the solidified mass of said fusible material said said particles.
Claim 20
Dependent Claim
34 words
A method as claimed in Claim 15 wherein said particles are electrically insulating and are formed of a good heat conducting material and are heated at the same time said fusible material is heated.
References Cited (Backward Citations)
No citation records indexed.
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