US 2405813 A
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Description (OCR text may contain errors)
Aug. 13, 1946. c. E. LQLANCHAUQD 2,405,813
Filed May 6, 1944 A V- lllllllllllllllllllllll l/ l/ /1/ l l l l l l Patented Aug. 13, 1946 DRIER Charles E. Blanchard, Randolph, Mass., assigner to B. F. Sturtevant Company, Hyde Park, Boston, Mass.
Application May 6, 1944, Serial No. 534,410
This invention relates to driers and relates more lparticularly to driers for drying tape which has been coated withv an adhesive.
The so-called industrial tape is coated on one side vwith an adhesive. The solvent in the adhesive has. to be removed by drying the tape before it is rolled up. In the driers now used, heated air is blown against both sides of the tape as it is moved through the driers. This results in too much' heat on the coated side causing case hardening of, and the formation of bubbles in, the coating.
This invention is a drier in which the major portion of the heat is applied to the uncoated side of the tape by infra-red lamps which boil oil the solvent. Tempered air is supplied to the coated side of the tape for aiding in the drying and for removing the solvent vapor.
An object of the invention is to dry coated tape and the like, without damaging the coating.
The invention will now be described with reference to the drawing, of which:
Fig. 1 is a View in vertical section of a drier embodying this invention, and
Fig. 2 is an end view of the drier of Fig. 1.
The tape 5 after having had its upper side coated with' adhesive in conventional equipment, passes between the rolls 6 and then through the inlet 1 of the dryer. The tape 5 is supported in the rollers 8 while in 'the dryer and after being dried as will be described, passes out the outlet 9.
The drier is divided into three compartments: I0, Il, and I2. In the first compartment I0, the infra-red lamps I3 are located under th'e tape 5 and supply heat for boiling the solvent from the coating upon the upper side of the tape.
The hood I4 is located in the compartment I0 above the tape 5 and has in its inlet, the baffles I5. The outlet I6 of the hood Iii is connected to the inlet of the exhaust fan I1. The wall I8 of the compartment Ill has an air inlet opening I9 therein and in alignment with which are placed the air heaters 20.
The fan I1 draws outdoor air through the heaters 20 and into the compartment I0 wh'ere it passes between the sides of the hood I4 and the upper vertical walls of the compartment I and into the inlet of the hood I4. The outdoor air tempered by the heaters 20 passes over the upper surface of the tape as it enters the h'ood I4 and acts to remove the solvent vapors evaporated from the coating on the tape and to aid in the drying of the tape. The solvent laden air is then exhausted by the fan I1 into the atmosphere or into a suitable solvent recovery system.
Itis desired not to overheat the coating on the tape 5 so that all the drying is not accomplished in the rst compartment l0. The partially dried tape after leaving the compartment I0 passes into the second compartment I0 where it passes over infra-red lamps, fewer in number than those in the compartment I0, and then into the th'ird compartment I2 where it passes over infra-red lamps, fewer in number than those in the compartment Il.
The perforated wall 2I extends over the 'tape 5in the compartments II and I2 and forms the lower wall of the plenum chamber 22. The chamber 22 has the air inlet 23 which is connected by the duct 24 to the outlet of the fan 25.
The air outlet 26 is in one of the vertical side walls of the drier, above the tape 5 in the compartments II and I2 and is Connected by the ducts 21 to the inlet of the fan 25. .The air heaters 28 are inserted between the ducts 21 in the path' of the air flow.
The duct 29 vents solvent laden air to the atmosphere or to a solvent recovery system. Fresh make-up air is drawn into the axial inlet of the fan 25 at 30.
The heated air from the plenum chamber 22 passes through the perforated wall 2| and passes over the tape before being exhausted 'through the outlet 26, and removes the vapors evaporated from the tape by the heat from the lamps I3, and aids in the drying.
By the use of the infra-red lamps for evaporating the solvents from the coating on the tape,
the heated air supplied in contact with .the coating on the tape is not depended upon for this function so that no intense heat is applied to the coating. As a result the coating is not case hardened, and no bubbles are formed therein.
By the use of the three described compartments in the drier, th'e drying is 'tapered from maximum in the first to minimum in the third with the result that the drying is completed in the dryer with the tape as it passes therefrom being relatively cool, so that it can be handled for being rolled up, etc.
While three compartments have been illustrated as being included in the drier, other arrangements involving features of this invention could be used.
While the material treated has been described as cooled tape, other material such, for example, as wire could be treated.
What is claimed is: 1. A drying system for drying coated tape and the like, comprising a housing containing a pluf rality of infra-red lamps, means for passing a tape to be dried past said lamps, whereby the heat from said lamps is applied to one side of said tape, a hood converging from its inlet to it's outlet, said hood having its inlet opposed to, and spaced from, said lamps, spaced baiiles in said inlet, an air heater, means including said housing dening a passage on opposite sides of and into said hood for air from said heater, and a fan connected to said outlet for drawing air through said heater and for withdrawing heated air and vapor from the other side of said tape. Y
2. A drier for coated tape and the like, comprising a housing containing avplurality of infrared lamps arranged in a row, means for passing a tape vto be dried past said lamps whereby heat y from said lamps is applied to one side of said tape, a hood converging from its inlet to its outlet, said hood having its inlet opposed to, and spaced from, lamps of said plurality, spaced baflles in said inlet, a fan connected to said outlet for withdrawing heated air and Vapor from the other side of said tape, a perforated wall opposed to and spaced from other lamps of said plurality, said other lamps being located downstream with respect to tape movement, from said lamps opposed to said hood inlet, an air heater, an air outlet between said passing means and said wall, and means for recirculating air through said heater, the perforations in said wall and said outlet.
3. A drier for coated tape and the like, comprising a housing containing a plurality of infrared lamps arranged in a row, means for passing a tape to be dried past said lamps whereby heat from said lamps is applied to one side of said tape, a hood converging from its inlet to its outlet, said hood having its inlet opposed to, and spaced from, lamps of said plurality, spaced bales in'said inlet, means for supplying heated air into said inlet, a fan connected to said outlet for withdrawing heated air and vapor from the other side of said tape, a perforated wall opposed to and spaced from other lamps of said plurality, said other lamps being located downstream with respect to tape movement, from said lamps opposed to said hood inlet, an air heater, an air outlet between said passing means and said Wall, and means for recirculating air through said heater, the perforations in said wall and said outlet CHARLES E. BLANCHARD.