Induction dryer

Patent metadata

Field	Value
Publication number	US-9814103-B2
Application number	US-201414298345-A
Country	US
Kind code	B2
Filing date	Jun 6, 2014
Priority date	Dec 9, 2002
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

In an induction heater, preheated, pressurized air is further heated in the heating cabinet and also drawn into the coil tube via a suction fan. The simultaneous pulling and pushing of the twice-heated air through the tube provides superior air flow to pick up more moisture from the can ends being dried. The tube ends rest on upwardly concave collars and are held in place by gravity, with a single screw acting as a stop above to prevent upward movement. Removal requires only removing the single screw at each end then lifting the tube straight up out of the cabinet, which is facilitated by providing a hinged cover on the cabinet.

First claim

Having described the invention, we claim:

1. An induction heating apparatus for heating workpieces moving through the apparatus, the apparatus comprising:
a housing;
a tube positioned within the housing and defining a generally enclosed space in the housing through which the workpieces travel as the workpieces move through the apparatus, the tube having an inlet end for receiving workpieces and an outlet end for discharging workpieces;
an inlet hub coupled to an opening in the housing, the inlet hub defining a first opening for receiving the workpieces prior to being received by the tube, the inlet hub configured to support the tube within the housing, and the inlet hub further defining a heated air inlet opening configured to enable air to flow therethrough from an interior of the housing to the enclosed space;
an induction coil configured to heat the workpieces as the workpieces move through the enclosed space;
a first fan operative to move air past power and control circuitry to a location within the housing; and
a second fan operative to move air through the heated air inlet opening into the enclosed space of the tube from the interior of the housing,
wherein the outlet end of the tube enables air to flow out of the enclosed space to an exterior of the housing.

2. The apparatus of claim 1 , wherein the second fan is a suction fan connected with the outlet end of the tube and operable to draw air through the enclosed space.

3. The apparatus of claim 1 , wherein the second fan is operable to push air from an interior of the housing into the enclosed space through the inlet end of the tube.

4. The apparatus of claim 1 , wherein the power and control circuitry is associated with the induction coil, the first fan being further operable to move air into the enclosed space through the inlet end of the tube.

5. The apparatus of claim 4 , wherein the housing is pressurized with heated air from the power and control circuitry associated with the induction coil.

6. The apparatus of claim 1 , wherein the second fan is located in the path of air flow from the outlet end of the tube and is operable to draw air out of the outlet end of the tube.

7. The apparatus of claim 6 , wherein the first fan is further operative to push air from an interior of the housing into the enclosed space through the inlet end of the tube.

8. The apparatus of claim 1 , further including a heater located inside the housing at the inlet end of the tube for heating air flowing into the tube.

9. The apparatus of claim 1 , wherein the housing has opposite end walls for supporting the tube, each one of the end walls having a support member on which a respective end of the tube rests to block downward movement of the tube end, each one of the end walls having a stop member movably connected with the end wall at a location above the tube end to block upward movement of the tube end, the tube being removable from the housing by lifting upward out of the housing.

10. A method of heating air and moving the heated air through a tube in an induction heating apparatus for heating workpieces that move through the tube, the tube being located in an enclosure with an induction heating coil extending around the tube in the enclosure, the method comprising:
receiving workpieces through a first opening defined by an inlet hub coupled to an opening in the enclosure prior to being received by the tube, the inlet hub configured to support the tube within the enclosure;
moving air past power and control circuitry to a location within the enclosure by a first fan; and
moving the air by a second fan through a heated air inlet opening defined by the inlet hub and into the interior of the tube from an interior of the enclosure and past workpieces that entered the tube through the inlet hub.

11. The method of claim 10 , wherein the second fan comprises a suction fan that is connected with the tube outlet, wherein moving the air into the interior of the tube comprises drawing the air into the tube by operation of the suction fan.

12. The method of claim 11 , wherein drawing the air into the interior of the tube comprises drawing the air from the enclosure into the tube.

13. The method of claim 10 , further comprising heating the air at a location spaced apart from the workpieces in the tube.

14. The method of claim 13 , wherein heating the air comprises preheating the air by moving the air past the power and control circuitry at a first location that provides power for an induction coil.

15. The method of claim 14 , wherein heating the air further comprises heating preheated air with a heater prior to moving the preheated air from the enclosure into the interior of the tube.

16. The method of claim 13 , wherein heating the air comprises heating the air with a heater prior to moving the air from the enclosure into the interior of the tube.

17. The method of claim 10 , wherein moving the air into the interior of the tube comprises pushing the air into the enclosure from a location outside the enclosure.

18. The method of claim 17 , wherein pushing air into the enclosure from a location outside the enclosure comprises pushing air that is preheated at the location outside the enclosure.

19. A heating apparatus for heating workpieces moving through the apparatus, the apparatus comprising:
a housing;
a tube positioned within the housing defining a generally enclosed space in the housing through which workpieces travel as the workpieces move through the apparatus, the tube having an inlet opening for receiving workpieces and an outlet opening for discharging workpieces;
an inlet hub coupled to an opening in the housing, the inlet hub defining a first opening for receiving the workpieces prior to being received by the tube, the inlet hub configured to support the tube within the housing, and the inlet hub further defining a heated air inlet opening configured to enable air to flow therethrough from an interior of the housing into the enclosed space;
means for heating the workpieces as the workpieces move through the enclosed space;
means for pressurizing air within the housing and moving the air past power and control circuitry; and
means for pulling air from the enclosed space of the tube to the outlet opening of the tube.

20. The apparatus of claim 19 , wherein the means for heating the workpieces comprises an induction coil extending around the tube.

21. The apparatus of claim 20 , wherein the means for pressurizing air within the housing comprises a fan, wherein the power and control circuitry is associated with the means for heating the workpieces.

22. The apparatus of claim 19 , wherein the means for pulling air from the enclosed space through the outlet opening of the tube comprises a suction fan connected with the outlet opening of the tube and operative to draw air through the enclosed space.

Assignees

• Nordson Corp

Inventors

• Wilson Timothy E
• Podolny Howard
• Baxter Raymond J

Classifications

• H05B6/101 Primary

  for local heating of metal pieces · CPC title

• H05B6/108

  for heating a fluid · CPC title

• H05B6/103

  multiple metal pieces successively being moved close to the inductor · CPC title

• F26B3/18

  by conduction, i.e. the heat is conveyed from the heat source, e.g. gas flame, to the materials or objects to be dried by direct contact · CPC title

• H05B6/10 Primary

  Induction heating apparatus, other than furnaces, for specific applications · CPC title