United States Patent [19]
Gellert
[ii] 4,438,325 [45] Mar. 20, 1984
[54] TUBULAR ELONGATED INJECTION
MOLDING ELECTRIC HEATING ELEMENT
WITH SPACER CLIPS
[76] Inventor: Jobst U. Gellert, 7A Prince St., Glen Williams, Canada
[21] Appl. No.: 334,154
[22] Filed: Dec. 24, 1981
[30] Foreign Application Priority Data
Dec. 10, 1981 [CA] Canada 392020
[51] Int. C1.3; H05B 3/06
[52] U.S. CI 219/536; 174/99 R;
219/421; 219/437; 219/523; 219/532; 219/548;
219/552; 425/551
[58] Field of Search 219/336, 421, 437, 438,
219/441, 475, 523, 530, 540, 542, 544, 548, 213, 402, 408, 526, 532, 536, 537, 552, 553; 425/144, 143, 548, 549, 568, 550, 551; 222/146 HE; 338/315; 174/99 R, 138 G, 138 J
[56] References Cited
U.S. PATENT DOCUMENTS
1,046,722 12/1912 Beadle 174/99 R
2,980,820 4/1961 Brundige et al 219/535
3,331,946 7/1967 Bilgro 219/535
3,394,243 7/1968 Lee 219/536 X
3,453,417 7/1969 Hummel 219/536
3,495,072 2/1970 Fischer 219/536 X
4,051,346 9/1977 Lenmark 219/536 X
4,066,201 1/1978 Blackmann 219/540 X
4,230,934 10/1980 Beck et al 219/421
4,238,671 12/1980 Gellert 219/421
4,241,291 12/1980 Carnes 219/536
4,279,588 7/1981 Gellert 425/568
4,287,408 9/1981 Wilson 219/421 X
4,304,544 12/1981 Crandell 425/549
4,344,750 8/1982 Gellert 425/548
Primary Examiner—Volodymyr Y. Mayewsky Attorney, Agent, or Firm—Riches, McKenzie & Herbert
[57] ABSTRACT
This invention relates to a spacer clip for an injection molding electric heating element. A number of clips, each formed of a continuous band, are slipped over one end of the heating element and slid along to predetermined positions. Each clip is then crimped to the heating element in that position which forms a finger which extends radially from the heating element in a predetermined orientation. The heating element with the spacer clips attached is located in a suitable mold for casting and the fingers of the clips locate each coil of the element with sufficient clearance from the mold and the other coils. The thickness of the conductive heater cast around the heating element is important to provide uniform heat transfer. The spacer clips are formed of a material such as stainless steel which has sufficient pliability to be securely crimped to the heating element, but sufficient strength to reliably retain the heating element in position. In one embodiment, the projecting finger may be twisted to give it additional regidity. This structure has the advantage over previous spacer plates that no extensive fault lines are formed by the spacer clips.
5 Claims, 8 Drawing Figures
