PARTS IMMERSION APPARATUS AND METHOD

Abstract

A parts immersion system and method includes a trough through which a conveyor belt carries the parts. A chemical solution is introduced into the trough through an opening in the bottom of the trough, from above the trough, and/or from the sides of the trough. The parts on the conveyor belt in the trough have a tendency to retard liquid movement out of the open ends of the trough thereby allowing the chemical solution to accumulate in the trough resulting in a greater immersion of the parts in the chemical solution. A gate may be provided near one or both ends of the trough to further enhance the accumulation of the chemical solution in the trough. Flights may extend upwardly from the conveyor belt to further enhance liquid retention in the trough between the flights. Flexible seals at the ends of the flights may contact sidewalls of the trough. One or more vibrators may be provided to enhance drainage of the chemical solution from the parts as the parts exit the trough.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description particularly refers to the accompanying figures in which:

FIG. 1 is a diagrammatic view of a parts immersion apparatus in accordance with this disclosure showing a trough, a conveyor belt routed through the trough and carrying parts that are stacked on each other in a random manner, a liquid flow port box which is situated beneath the trough and which directs liquid upwardly into a central region of the trough, the liquid flowing over the parts on the conveyor belt and exiting open ends of the trough for collection by a pair of collector tanks, the collector tanks coupled to an accumulator tank, and a pump which pumps liquid from the accumulator tank to the liquid flow port box;

FIG. 2 is a perspective view of the trough, the liquid flow port box, portions of the collector tanks, and portions of the conveyor belt, showing the trough having spaced vertical side walls, the conveyor moving parts through the trough between the side walls and above a bottom wall of the trough, liquid being pumped upwardly into the trough through the liquid flow port box, the trough having a pair laterally extending channel members interconnecting the side walls of the trough, liquid being directed into respective channel members by respective liquid delivery pipes, the liquid filling the channel members and overflowing downwardly into the trough, and the liquid flowing out of the open ends of the trough into the collector tanks;

FIG. 3 is a cross sectional view showing the liquid flow port box having movable baffles which are moved to adjust the size of an outlet orifice from the liquid flow port box and showing an alternative embodiment of a trough having end regions of the bottom wall sloped downwardly to direct the liquid exiting the trough into the collector tanks;

FIG. 4 is a diagrammatic view showing the liquid being introduced near a raised end of an inclined trough, the liquid primarily moving downwardly through the trough under the influence of gravity, and the conveyor belt carrying the parts at an upward incline through the trough such that the parts move against the primary flow of the liquid in a countercurrent arrangement;

FIG. 5 is a diagrammatic view showing liquid being introduced near a central region of an inclined trough, the liquid primarily moving downwardly through the trough under the influence of gravity, and the conveyor belt carrying the parts at a downward incline though the trough such that the parts move with the primary flow of the liquid in a concurrent arrangement;

FIG. 6 is a diagrammatic view showing liquid being introduced near the ends of the trough and draining out of the trough at a central region thereof;

FIG. 7 is a cross sectional view showing the trough having short end walls near the ends of the trough and the conveyor belt sagging downwardly relative to the end walls so as to descend into the trough and ascend out of the trough thereby achieving a greater depth of immersion of the parts in the chemical solution in the trough;

FIG. 8 is a sectional view showing gates at the ends of the trough, a set of actuators coupled to the gates, and the actuators being operable to move the gates from respective closed positions (in solid) enhancing the retention of chemical solution in the trough and opened positions (in phantom) away from the closed positions;

FIG. 9 is a top plan view showing the gates extending from one side wall of the trough to the other;

FIG. 10 is a sectional view showing a series of spaced apart flights coupled to the conveyor belt and extending upwardly therefrom;

FIG. 11 is a top plan view showing flexible seals at the ends of the flights contacting the side walls of the trough;

FIG. 12 is a sectional view showing first and second spaced apart troughs through which parts are conveyed on a single conveyor belt for immersion in respective first and second chemical solutions; and

FIG. 13 is a top plan view showing a vibrator coupled to a wall that spans the gap between the first and second troughs.

Claims

1. An apparatus for applying a chemical solution to parts, the apparatus comprising a conveyor belt on which the parts are placed,a trough having a channel through which the conveyor belt is routed,a liquid delivery system operable to introduce the chemical solution into the trough, wherein the chemical solution is retained in the channel of the trough and flows toward at least one end of the trough to be discharged under the influence of gravity, and wherein the parts on the conveyor belt have a tendency to retard movement of the chemical solution toward the at least one end of the trough thereby enhancing accumulation of the chemical solution in the trough and resulting in a greater immersion of the parts in the chemical solution.

2. The apparatus of claim 1, further comprising a reservoir to collect the chemical solution that exits the trough.

3. The apparatus of claim 1, wherein the trough has end walls and the conveyor belt is routed down into the trough and up out of the trough in order to achieve a greater depth of immersion.

4. The apparatus of claim 1, wherein the liquid delivery system includes at least one of pipes, overflowing weirs, and spray nozzles for introducing the chemical solution into the trough.

5. The apparatus of claim 1, wherein the liquid delivery system is operable to introduce the chemical solution into the trough at multiple locations, with independent control over at least one of the discharge velocity and the volume at one or more of the multiple locations.

6. The apparatus of claim 1, wherein the trough has at least one drainage opening spaced from the ends of the trough.

7. The apparatus of claim 1, further comprising a sloped pan near one of the end of the trough and a collection tank, the sloped pan being arranged so that at least some of the chemical solution flows to the collection tank down the sloped pan.

8. The apparatus of claim 1, wherein a bottom wall of the trough is sloped downwardly in one of a first direction and a second direction, the first direction being in a same direction as conveyor belt travel and the second direction being in an opposite direction of conveyor belt travel.

9. The apparatus of claim 1, wherein the liquid delivery system is operable so that at least some of the chemical solution is introduced into the trough with a direction and velocity in one of a first direction and a second direction, the first direction being in a same direction as conveyor belt travel and the second direction being in an opposite direction of conveyor belt travel in the direction of conveyor belt travel.

10. The apparatus of claim 1, further comprising an air discharger near at least one end of the trough to discharge air with a directional component that impedes the flow of the chemical solution out of the trough, thereby increasing the immersion of the parts.

11. The apparatus of claim 1, further comprising a movable gate near at least one end of the trough, the gate having a closed position to retard the chemical solution from exiting the trough so as to increase the amount of chemical solution retained in the trough near the at least one end, and the gate having an opened position moved away from the closed position.

12. The apparatus of claim 1, further comprising a vibrator coupled to the trough and operable to vibrate the trough to enhance drainage of the chemical solution from the parts as the parts exit from the trough.

13. The apparatus of claim 1, further comprising flights extending upwardly from the conveyor belt, the flights being configured to retard liquid movement out of the trough.

14. The apparatus of claim 13, further comprising seals coupled to the flights, the seals being configured to contact sidewalls of the trough as the flights move through the trough.

15. The apparatus of claim 1, further comprising a restraining mechanism above the conveyor belt and above the parts to prevent the parts from floating on top of the chemical solution in the trough.

16. A method for applying a chemical solution to parts, the method comprising placing the parts on a conveyor belt,moving the parts on the conveyor belt through a trough having a channel through which the conveyor belt is routed, andintroducing the chemical solution into the trough, wherein the chemical solution is retained in the channel of the trough and flows toward at least one end of the trough to be discharged under the influence of gravity, and wherein the parts on the conveyor belt have a tendency to retard movement of the chemical solution toward the at least one end of the trough thereby enhancing accumulation of the chemical solution in the trough and resulting in a greater immersion of the parts in the chemical solution.

17. The method of claim 16, further comprising directing at least some of the chemical solution exiting the trough to a different process after exiting the trough.

18. The method of claim 16, further comprising collecting the chemical solution exiting the trough in a reservoir.

19. The method of claim 16, further comprising securing the parts on the conveyor.

20. The method of claim 16, wherein the introduction of the chemical solution into the trough and the action of gravity on the chemical solution creates substantial movement of the chemical solution over the parts on the conveyor belt.

21. The method of claim 16, wherein the chemical solution is introduced into the trough through pipes, overflowing weirs, or spray nozzles.

22. The method of claim 16, wherein the chemical solution is introduced into the trough at a singular location or at multiple locations, with independent control over the discharge velocity and volume at any or all locations of liquid introduction.

23. The method of claim 16, further comprising draining the chemical solution from the trough at a location in addition to the at least one end of the trough.

24. The method of claim 16, wherein the introduction of the chemical solution into the trough causes movement of parts.

25. The method of claim 16, wherein the chemical solution is introduced in a direction and at a velocity such that the movement of the chemical solution out of the at least one end of the trough is further inhibited and the resulting immersion of parts in the trough is increased.

26. The method of claim 16, wherein at least some of the chemical solution flows to a collection tank down sloped pans which eliminate free fall of the chemical solution thereby to reduce foam generation.

27. The method of claim 16, wherein concurrent movement of the parts and chemical solution is achieved at least in part due to a bottom wall of the trough being sloped in the direction of conveyor belt travel.

28. The method of claim 16, wherein at least some of the chemical solution is introduced into the trough with a direction and velocity in the direction of conveyor belt travel in order to achieve at least in part concurrent movement of the parts and the chemical solution.

29. The method of claim 16, wherein countercurrent movement of the parts and the chemical solution is achieved at least in part due to a bottom wall of the trough being sloped opposite the direction of conveyor belt travel.

30. The method of claim 16, wherein at least some of the chemical solution is introduced into the trough with a direction and velocity opposite the direction of conveyor belt travel in order to achieve at least in part countercurrent movement of the parts and the chemical solution.

31. The method of claim 16, further comprising discharging air near the at least one end of the trough with a directional component which also impedes the flow of the chemical solution out of the trough.

32. The method of claim 16, wherein the conveyor belt descends into the trough and ascends out of the trough due to catenary sag of the conveyor belt between supports.

33. The method of claim 16, further comprising moving a movable gate near at least one end of the trough between a closed position to retard the chemical solution from exiting the trough so as to increase the amount of chemical solution retained in the trough near the at least one end and an opened position moved away from the closed position.

34. The method of claim 16, further comprising operating a vibrator to vibrate the trough to enhance drainage of the chemical solution from the parts as the parts exit from the trough.

35. The method of claim 16, wherein placing parts on the conveyor belt comprises placing parts between flights that extend upwardly from the conveyor belt.

36. The method of claim 16, wherein the parts to be immersed in the chemical solution are buoyant and further comprising placing a restraining mechanism above the conveyor belt and above the buoyant parts to prevent the buoyant materials from floating on top of the chemical solution in the trough.