ELECTRIC HEATERS

• US 3,736,405 A
• Filed: 11/24/1971
• Issued: 05/29/1973
• Est. Priority Date: 11/24/1971
• Status: Expired due to Term

• Current Assignee: Charles E. Bryson Jr, Gary I. Barton
• Original Assignee: Charles E. Bryson Jr, Gary I. Barton
• Inventors: Bryson, Charles E. Jr., Barton, Gary I.
• Primary Examiner(s): Mayewsky, Volodymyr Y.
• Application Number:
  US05/201,753
• Time in Patent Office: 552 Days
• Field of Search: 219/260,261,267,270,521,523,541,544 110/1F,8E,28D 317/9B 126/59.5 156/272 174/75C,76,78,88C 29/621
• US Class Current: 219/270
• CPC Class Codes: A47J 37/079 Charcoal igniting devices
• CPC Class Codes: F23Q 7/02 for igniting solid fuel

Abstract

A sheathed electric heater, particularly of the charcoal lighter type, having a resistor within the sheath, terminal pins electrically connected to the ends of the resistor, and an insulated power supply cord having a pair of current conductors electrically connected to respective terminal pins, the improvement comprising a handle for the heating element which is formed of electric insulating material and molded around adjoining parts of the sheath and cord and extending unbroken therebetween to completely encapsulate such parts, the terminal pins extending from the sheath and the electrical connection between the terminal pins and the current conductors.

Claims

1. An electric heating element, such as a charcoal lighter and the like, comprising a metal sheath having an intermediate bight portion and legs in closely spaced side-by-side relation, a resistor within said sheath, terminal pins electrically connected to respective ends of said resistor and each terminal pin extending outwardly from a respective sheath end, compacted refractory material within said sheath to electrically insulate said resistor and said terminal pins from said sheath and to conduct heat generated by said resistor to said sheath, and an insulated power cord having a pair of current conductors which are electrically connected to respective terminal pins, said cord being adapted to be connected to a source of electrical energy to cause said resistor to generate heat, the improvement comprising:

a handle for said heating element comprising an encapsulation of the ends of said sheath legs and the space therebetween and said terminal pins and their connection to said power cord and the end of the power cord adjacent to said connection, the encapsulation consisting of a cellular urethane plastic which in uncured state occupies only a part of a mold closed about the parts above mentioned and which expands upon application of heat to completely fill the mold and surround and adhere to said parts, the plastic upon subsequent cooling and removal from said mold forming a one-piece rigid handle of cellular cross-section, said handle forming a rigid electrically insulating member by which said heating element may be safely handled, and through adherence to said power cord end forms a strain relief for the electrical connections between said terminal pins and said power cord conductors, the density of the cellular urethane plastic is in the general order of 20 pounds per cubic foot.

2. An electric heating element, such as a charcoal lighter and the like, comprising a metal sheath having an intermediate bight portion and legs in closely spaced parallel relation and diverge toward said bight portion, a resistor within said sheath, terminal pins electrically connected to respective ends of said resistor and each terminal pin extending outwardly from a respective sheath end, compacted refractory material within said sheath to electrically insulate said resistor and said terminal pins from said sheath and to conduct heat generated by said resistor to said sheath, and an insulated power cord having a pair of current conductors which are electrically connected to respective terminal pins, said cord being adapted to be connected to a source of electrical energy to cause said resistor to generate heat, the improvement comprising:

a handle for said heating element comprising an encapsulation of the ends of said sheath legs and the space therebetween and said terminal pins and their connection to said power cord and the end of the power cord adjacent to said connection, the encapsulation consisting of a cellular urethane plastic which in uncured state occupies only a part of a mold closed about the parts above mentioned and which expands upon application of heat to completely fill the mold and surround and adhere to said parts, the plastic upon subsequent cooling and removal from said mold forming a one-piece rigid handle of cellular cross-section, said handle forming a rigid electrically insulating member by which said heating element may be safely handled, and through adherence to said power cord end forms a strain relief for the electrical connections between said terminal pins and said power cord conductors, and a sheet-metal shield including a body portion overlying the legs of said heating element and having opposite ends bent in the same direction from said body portion, each end having a pair of openings which closely but slidably receive parallel parts of said legs, movement of said shield in a direction toward the bight portion of said sheath being limited by wedging action of the defining surfaces of the openings in the end of the shield nearest the bight portion with the diverging legs, the opposite end of said shield being disposed close to the adjacent portion of the handle and adapted to be disposed outside of the mold and engageable with an exterior mold surface to longitudinally position parts within the mold.