US2970813A - Circulating units for paint preheaters - Google Patents

Description

Feb. 7, 1961 L. BECK 2,970,813

CIRCULATING UNITS FOR PAINT PREHEATERS Filez'` June 5. 1957 1NVENT0R. 0a/5 Bic/f /7 TTORNEY UnitedStates Patent O Fce CIRCULATING UNITS FOR PAINT PREHEATERS This invention relates to paint preheaters, generally of the type and kind disclosed in my prior application Seri-al Number 477,551, filed December 24, 1954, issued in Patent No. 2,802,089, granted August 6, 1957. More particularly, the invention deals with a paint circulating unit for preheaters of this type and kind. Still more particularly, the invention deals with a circulating unit, wherein detachment of a fitting element, including the intake circulating pipe, will facilitate cleaning of the unit from time to time.

Further, the invention deals with a multiple finned sleeve for forming circulating passages directly exposed to the radiation of heat through said fins for highly eiiicient operation of the preheater.

The novel features of the invention will be best under stood from the following description, when taken together with the accompanying drawing, in which certain embodiments of the invention `are disclosed and, in which, the separate parts are designated by suitable reference characters in each of the views and, in which:

Fig. l is a broken side and sectional View of a circulating unit made according to my invention, indicating, in part in dot-dash lines, the preheatercasing or housing, in which the unit is arranged; and

Fig. 2 is a section on theline 2 2 of Fig. 1.

In practice, I provide a unit comprising a body part 11, generally of hexagon cross-sectional form, the body part having an upwardly directed short tubular extension 12, suitably fixed and secured within the heater casing or housing, which is indicated, in part, in dot-dash lines at 13.

Considering my prior application, above identified, the casing of the preheater also includes an outer wall of insulation in order to maintain the heat within the casing, but, as my invention deals simply with the circulating unit, all detail reference to the preheater is eliminated in order to simplify the showing.

The body 11 is generally tubular in form and has a circulatingchamber 14, the lower end of which isinternally threaded, as seen at 15, to detachably receive a fitting head orelement 16. Theelement 16 has an externally threadedportion 17 mounted in the threaded portion of the body 11, as clearly seen at the right of Fig. l. Theportion 17 terminates in an upwardly extended reducedportion 18 internally threaded to receive a long circulating pipe ortube 19, which becomes part of theelement 16 insertable into and removable from the body 11, particularly in cleaning the unit from time to time.

Outwardly of theportion 17 is a generally circular enlargedportion 20, having flattened sides, one of which 2,970,813 Patented Feb. 7, 1961 as the intake fitting; whereas, thefitting 24 is the recirculating fitting. With these fittings are coupled flexible tubes, through which paint is introduced into the unit through thefitting 23 and, whenever desired and when the discharge gun of preheaters of this type and kind is not in operation, the paint can be re-circulated by passage through thefitting 24 and the tube, not shown, which is coupled therewith.

Thepipe 19 is mounted in the other single passage of theY passage 22, as will be apparent. Mounted and seated within the extension 12 of the body 11 is anelongated tube 25, in which is fitted afinned sleeve 26. The sleeve '26 extends to a position short of the upper end of thetube 25 and seats against a closure disc orplate 27 fitted in thetube 25, as noted at the top of Fig. 1 of the drawing.

Thesleeve 26 has a plurality of circumferentially spaced long inwardly directed fins 2S and short inwardly directed fins 29. Thelong fins 28 extend radially inwardly to a point seating upon thetube 19; whereas theshort fins 29 terminate short of the tube 1.9, as clearly illustrated in Fig. 2 of the drawing. 'It will, thus, be seen that heat from theheater casing 13 not only heats the Wall of thesleeve 26, but also will radiate heat through thelong hns 28 to heat thetube 19 and these radiatingfins 28 and 29 also serve to heat the paint circulating downwardly through thesleeve 26 upon being discharged from the upper end of thetube 19, this circulating being illustrated by the arrows in Fig. 1. The paint enters theelement 16 through the intake fitting 23, and, then, passes up through thetube 19.

Mounted in one side of the body 11 is adischarge pipe 30, which communicates with the circulatingchamber 14. All of the passages in thesleeve 26 open into thechamber 14, as will clearly appear from a consideration of Fig. 1, so that the heated paint is free to pass through thedischarge pipe 30 and extend to the usual gun for 'applying the paint to a surface, it being understood that a exible tube is also coupled with the end portion of thepipe 30, as with other devices of this type and kind.

It will appear from a consideration of Fig. l of the drawing that the upper end 19' of thetube 19 terminates short of the closure disc orplate 27 for free discharge of the paint passing upwardly through the tube into the passages formed between thefins 23, which passages are sub-divided to an extent by thefins 29, as will be apparent from a consideration of Fig. 2.

In addition to the attachment and detachment of theelement 16 with respect to the body 11 in cleaning the unit, in some instances, the entire unit can be removed from theheater casing 13 without in any way disturbing the structure features of this unit. In other words, thedischarge pipe 30 is positioned beyond the limits of thecasing 13, different in this respect from the illustration in my prior application, hereinbefore identified.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. A circulating unit for paint preheaters, said unit comprising a tubular body portion having a threaded bore opening through one end, a fitting element arranged within and in threaded engagement with said bore and including an inlet fitting for introduction of paint into said element, an elongated intake pipeV coupled with said element and through which paint is adapted to be circulated, a discharge pipe coupled with the body portion and communicating with the circulating chamber in said body and around the base of said pipe, an elongated tube mounted in and extending beyond the upper end of said body portion, a closure for the upper end of said tube, a radiating sleeve arranged snugly in said tube around and widely spaced from said intake pipe, said sleeve extending to said closure and having inwardly extending long-A and short radiating fins, the long fins extending to and engaging the surface of said intake pipe, and said ns forming, around the intake pipe and within said sleeve, a plurality of circulating passages opening into theA circulating chamber of said body portion for discharge through said discharge pipe.

2. A circulating unit as defined inclaim 1 wherein said body portion is hexagon in cross-sectional form, and said fitting element having flattened sides, facilitating rotation of the element in attachment and detachment of the element with respect to said body portion.

3. A circulating unit as defined inclaim 1 wherein the fins of said sleeve extend the full length thereof.

References Cited in the le of this patent UNITED STATES PATENTS Schmitz Feb. 27, Doble Dec. 16, Mott June 5, Lehane et al. Mar. 27, Jantsch Dec. 19, Brown Aug. 18, Roswell f, r, r ...,v Apr. 12,

FOREIGN PATENTS SwedenV Apr. 2,

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