| US 7,351,937 B2 | ||
| Control circuits for hot melt adhesive heater circuits and applicator heads | ||
| Dieter B. Heerdt, Hendersonville, Tenn. (US); and Andreas Pahl, Erkrath (Germany) | ||
| Assigned to Illinois Tool Works Inc., Glenview, Ill. (US) | ||
| Filed on Feb. 02, 2006, as Appl. No. 11/345,320. | ||
| Application 11/345320 is a continuation in part of application No. 11/123028, filed on May 06, 2005, granted, now 7,332,692. | ||
| Prior Publication US 2006/0289566 A1, Dec. 28, 2006 | ||
| Int. Cl. H05B 1/02 (2006.01) | ||
| U.S. Cl. 219—486 [219/483; 219/501; 219/497; 219/508; 307/39] | 11 Claims |
| 1. An electronic control circuit for use in connection with hot melt adhesive dispensing equipment, comprising:
an electrical power source;
a relatively large applicator head which is effectively divided into a plurality of zones;
a plurality of heater assemblies distributed throughout said relatively large applicator head such that one of said plurality
of heater assemblies is disposed within each one of said plurality of zones defined within said relatively large applicator
head, wherein each one of said plurality of heater assemblies is operatively associated with each one of said plurality of
zones defined within said relatively large applicator head so as to heat the hot melt adhesive material, being fluidically
conducted internally within each one of said plurality of zones defined within said relatively large applicator head, to a
predetermined temperature level;
a plurality of temperature sensors distributed throughout said relatively large applicator head such that one of said plurality
of temperature sensors is disposed within each one of said plurality of zones defined within said relatively large applicator
head, wherein each one of said plurality of temperature sensors is operatively associated with each one of said plurality
of zones defined within said relatively large applicator head so as to effectively sense the temperature level of the hot
melt adhesive material being fluidically conducted internally within each one of said plurality of zones of said relatively
large applicator head, and to effectively control the energization of each one of said plurality of heater assemblies disposed
within each one of said plurality of zones defined within said relatively large applicator head so as to maintain the temperature
level of the hot melt adhesive material, being conducted internally within each one of said plurality of zones defined within
said relatively large applicator head, at said predetermined temperature level;
switching means for selectively electrically connecting each one of said plurality of heater assemblies, disposed within each
one of said plurality of zones defined within said relatively large applicator head, to said electrical power source; and
means for controlling said switching means, in response to temperature levels respectively sensed by said plurality of temperature
sensors, so as to selectively electrically connect particular ones of said plurality of heater assemblies to said electrical
power source in order to selectively maintain each one of said plurality of zones of said relatively large applicator head
at said predetermined temperature level.
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