Heat-responsive element for fire protection sprinklers or the like

In a fire protection sprinkler head of the type including a base having a throat of predetermined cross-section through which a stream of fire retardant fluid can flow,

• the improvement wherein
• said fire protection sprinkler head further comprises a heat-responsive element comprising two link members joined with a thin solder layer in a face-to-face relationship over an extended surface area, the components of opposed surfaces of said link members in contact with said solder layer and said solder layer being adapted to alloy with each other in the regions immediately adjacent each of said opposed surfaces to form alloy bonds between said opposed surfaces and said solder layer, the strength of said alloy bonds being greater than the strength of said solder layer, and at least said opposed surfaces of said link members comprises an alloy-forming amount of a member selected from the group consisting of nickel, cobalt, chromium and iron, or of an alloy of a member selected from the group consisting of nickel, cobalt, chromium, and iron.

A process for preparing a heat-responsive element comprising joining two link members with a thin solder layer in a face-to-face relationship over an extended surface area under conditions sufficient to form alloy bonds between opposed surfaces of said link members in contact with said solder layer and said solder layer in the regions immediately adjacent said opposed surfaces, the strength of said alloy bonds being greater than the strength of said solder layer, and said opposed surfaces of said link members comprise an alloy-forming amount of a member selected from the group consisting of nickel, cobalt, chromium and iron.

A heat-responsive element comprising two link members joined with a thin solder layer in a face-to-face relationship over an extended surface area,

• the components of opposed surfaces of said link members in contact with said solder layer and said solder layer being adapted to alloy with each other in the regions immediately adjacent each of said opposed surfaces and said solder layer, the strength of said alloy bonds being greater than the strength of said solder layer, and at least said opposed surfaces of said link members comprise an alloy-forming amount of nickel, or an alloy of nickel.

In a fire protection sprinkler head of the type including a base having a throat of predetermined cross-section through which a stream of five retardant fluid can flow,

• the improvement wherein
• said fire protection sprinkler head further comprises a heat-responsive element comprising two link members joined with a thin solder layer in a face-to-face relationship over an extended surface area, the components of opposed surfaces of said link member in contact with said solder layer and said solder layer being adapted to alloy with each other in the regions immediately adjacent each of said opposed surfaces to form alloy bonds between said opposed surfaces and said solder layer, the strength of said alloy bonds being greater than the strength of said solder layer, and at least said opposed surfaces of said link members comprise an alloy-forming amount of nickel, or an alloy of nickel.