US862046A - Flue construction for bake-ovens. - Google Patents

Flue construction for bake-ovens. Download PDF

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US862046A
US862046A US352846A US1907352846A US862046A US 862046 A US862046 A US 862046A US 352846 A US352846 A US 352846A US 1907352846 A US1907352846 A US 1907352846A US 862046 A US862046 A US 862046A
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flues
flue
chamber
passages
baking chamber
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US352846A
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Frederick R Barnheisel
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    • AHUMAN NECESSITIES
    • A21BAKING; EDIBLE DOUGHS
    • A21BBAKERS' OVENS; MACHINES OR EQUIPMENT FOR BAKING
    • A21B1/00Bakers' ovens
    • A21B1/40Bakers' ovens characterised by the means for regulating the temperature

Definitions

  • This invention relates more particularly to the flue and baking chamber structure of a rotary bake oven, although the invention is not necessarily limited to use in connection with a rotary baking table or plane.
  • the object of the invention is to improve the construction and arrangement of flues above and below the baking chamber for the purpose of uniformly heating the chamber and utilizing the heated products of combustion to their fullest extent prior to their discharge from the oven structure.
  • Another object of the invention is to so arrange the flues that the heated air and gases may be directed either into or around the baking chamber, which affords a means for quickly heating the oven prior to the baking operation and thereafter maintaining its heated condition without bringing the heated gases into direct contact with the food being baked.
  • Another object of the invention is to so arrange the flues and passages that they may be readily cleaned out either from the front or rear, and the invention finally consists in the features of construction and combination of parts hereinafter described and claimed.
  • Figure 1 is a sectional elevation from side to side of the oven showing the interior arrangement;
  • Fig. 2 a sectional plan view of the lower flues taken on line 22 of Fig. 1;
  • Fig. 3 a sectional plan view of the upper flues taken on line 33 of Fig. 1;
  • Fig. 4 a longitudinal sectional elevation of the front of the oven;
  • Fig. 5 a sectional elevation taken on line 55 of Fig. 4;
  • Fig. 6 a sectional elevation of the rear portion of the oven.
  • the oven is constructed of brick, is substantially cylindrical in shape, and is provided in its bottom with a series of air spaces 1, best shown in Fig. 1, which air spaces surround a solid central foundation 2 which supports the baking plane, and above the air spaces are arranged a series of lower flues, best shown in Fig. 2.
  • the lower flues communicate with a fire chamber 3 having located thereina grate 4, behind which is a transversely extending bridge wall 5, and the fire box communicates with a central flue chamber 6 having straight parallel side walls 7 which terminate in curved inner flue walls 8, whose terminal ends 9 are separated from one another by a central partition wall 10 which terminates at its inner end in a central circular wall 11, in the middle of which is a circular recess 12 which forms a well for the step of the rotary shaft which carries the baking plane.
  • Surrounding the inner flue walls 8 are curved intermediate flue walls 13 connected at their outer ends with straight partition walls 14 which are parallel with and separated from the central parti tion Wall 10.
  • outer curved partition walls 15 terminating at their forward end in straight partition walls 16, which are parallel with and separated from a pair of walls 17 which inclose the fire chamber and are in effect continuations of the walls 7 of the flue chamber.
  • the curved outer walls 18 of the oven which arrangement of flue walls provides a series of curved flue passages, the intake openings for the passages being in staggered relation so as to provide a devious path of travel for the heated air and products of combustion from the fire chamber.
  • the several flue passages may be designated as the inner flue passage 19, the first intermediate flue passage 20, the second intermediate flue passage 21, and the outer flue passage 22.
  • the outer flue passage terminates in a vertical flue 23 which connects with the upper flues, which are best shown in Fig. 3.
  • the upper flues are of similar formation to the lower flues, and consist of outer flue passages 24, intermediate flue passages 25 and 26, and inner flue passages 27, the several passages being separated one from the other by means of concentric outer, intermediate and inner curved walls 28, 29, and 30, respectively.
  • the upper flues on opposite sides of the oven are separated by means of a central partition wall 31 which extends from front to rear of the furnace, and is provided at its center with a rounded supporting post or column 32 through which passes the rotary shaft for the baking plane.
  • the upper flues like the lower,
  • the inner curved flue passages 27 terminate in forwardly extending straight passages 33 which connect with vertically extending passages 33 connecting with the discharge flue 34 which connects with the chimney for the oven.
  • the lower flues are provided with forwardly extending inner clean-out passages 35 and outer clean-out passages 36, the lower flues being provided at their rear ends with inner clean-out passages 37 and outer clean-out passages 38, which arrangement allows the various passages to be cleaned for the purpose of removing soot or products jof combustion.
  • the upper flue passages are likewise provided with forwardly extending inner clean-out passages 39 and outer passages 40, which passages are supplemented by inner clean-out passages 41 and outer clean-out passages 42 at the rear end of the furnace.
  • Access is had to the interior of the fire chamber through an opening 48 in the front of the furnace, and access is had to the interior of the baking chamber through an opening 49 in the rear wall of the baking chamber.
  • the various clean-out passages may be closed by means of doors 50 of any suitable character, and likewise the opening 48 may be closed by means of a door 51.
  • the dampers 45 controlling communication between the lower flues and the baking chamber are opened and the damper 47 controlling the draft from the baking chamber to the chimney is likewise opened, thereby establishing a direct draft through the baking chamber which serves to divert the progress of the heated air from the upper flues to the baking chamber, which serves to heat the baking chamber from within as well as from without, when so desired.
  • the same flue and chamber structure can, without any material modification, be used as an oven of the stationary type; and the method of directing the heated gases and products of combustion either into or around the bakingchamber is of general application, since the flue and chamber structure has no necessary dependence upon the particular method by which the bakery products are supported within the baking chamber.
  • a bake oven the combination of a circular baking chamber, a plurality of semi-circular, sinuous and connecting lower flues, a plurality of semi-circular, sinuous and connecting upper flues, a passage connecting each set of lower flues with the companion set of upper flues, a discharge flue connecting with the upper flues, passages connecting the lower flues with the baking chamber, a damper for controlling each of said last named passages, and a passage leading from the baking chamber to the discharge flue, substantially as described.
  • a bake oven the combination of a circular baking chamber, a plurality of semi-circular and sinuous lower heating flues beneath the floor of the baking chamber, a fire chamber in communication with the lower heating flues, a vertically extending passage leading from each set of lower heating flues through the floor of the baking chamber, a discharge flue in communication with the lower heating flues, a damper for controlling each vertical passage between the lower heating flues and the baking chamber, and a passage leading from the baking chamber to the discharge flue, substantially as described.
  • a bake oven the combination of a circular baking chamber, a plurality of semi-circular, sinuous 'and connecting lower heating flues beneath the floor of the baking chamber, a fire chamber in communication with the lower heating flues, a vertically extending passage leading from each set of lower heating flues through the floor of the baking chamber, a damper for controlling each of the last named passages, a plurality of semi-circular, sinuous and connecting upper heating flues above the roof of the baking chamber and in communication with the lower heating flues, a discharge flue connecting with the upper heating flues, and a discharge passage leading" from the baking chamber to the discharge flue, substantially as described,
  • a baking chamber In a bake oven, a baking chamber, a fire chamber, a central flue chamber leading from the fire chamber, a series of semi-circular and sinuous lower flues on each side of and in communication with the central flue chamber, located below the baking chamber and formed by concentric curved walls with adjoining flues ot' a series open at opposite ends to provide a sinuous passage for the products of combustion, a series of semi-circular and sinuous upper flues corresponding to and connecting with the lower flues and located above the baking chamber, vertical passages connecting the discharge end of each lower outer flue with the intake end of each upper outer flue, and a discharge fine in communication with each of the inner upper flues, substantially as described.
  • a baking chamber In a bake oven, a baking chamber,'a fire chamber, a central flue chamber leading from the fire chamber, a series of semi-circular and sinuous lower flues on each side of and in combination with the central flue chamber, located below the baking chamber and formed by concentric curved walls, With adjoining flues of a series open at opposite ends to provide a sinuous passage for the products of combustion, a series of semi-circular and sinuous upper flues corresponding to and coinciding with the lower series of flues and located above the baking chamber, a vertical passage connecting the discharge end of each lower outer flue-with the intake end of its companion upper outer flue, a discharge flue in communication with the inner upper flues, passages leading from the baking chamber to the discharge flue, and dampers for regulating the passage of the products of combustion through the flues, substantially as described.
  • a circular baking chamber a fire chamber, a central flue passage communicating with the fire chamber, concentric inner intermediate and outer lower flues located below the baking chamber on each side of the central flue passage and separated from each other by curved walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, a rear lower wall in line with the center of the fire chamber, concentric upper flues above the baking chamber, consisting of concentric inner, intermediate and outer flues corresponding to and coinciding with the lower flues and separated from each other by curved Walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, an upper center partition wall extending from front to rear of the oven, a passage connecting the discharge end of each outer lower flue with the intake end of the companion outer upper flue, a discharge flue, and a passage connecting the discharge end of each inner upper flue with the discharge flue, substantially as described.
  • a circular baking chamber In a bake oven, a circular baking chamber, a fire chamber, a central flue passage communicating with the fire chamber, concentric inner, intermediate and outer lower flues below the baking chamber on each side of the central flue passage and separated from each other by curved Walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, a rear lower wall in line with the center of the fire chamber, concentric upper flues above the baking chamber, consisting of concentric inner, intermediate and outer flues corresponding to and coinciding with the lower fines and separated from each other by curved Walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, an upper center partition wall extending from front to rear of the oven, a passage connecting the discharge end of each outer lower flue with the intake end of the companion outer upper flue, a discharge flue, a passage connecting the discharge end of each inner upper flue with the discharge flue, a flue leading from the baking 4 chamber to the discharge flu

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Food Science & Technology (AREA)
  • Baking, Grill, Roasting (AREA)

Description

PATENTED JULY 30, 1907..
APPLIOATIOH FILED JAN. 18, 1907.
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PATEN'TED JULY 30, 1907..
I. R. BARNHBISBL! I FLUB CONSTRUCTION FOR BAKE OVENS.
LPPLIOATIOK FILED JAN. 18. 1907.
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FREDERICK R. BARNHEISEL, OF CHICAGO, ILLINOIS FLUE CONSTRUCTION FOR BAKE-OVENS.
Specification of Letters Patent.
Patented July 30, 1907.
Original application filed October 17, 1905, Serial No. 283,121. Divided and this application filed January 18, 1907.
Serial No. 352,846.
To all whom it may concern:
Be it known that I, FREDERICK R. BARNHEISEL, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Flue Construction for Bake-Ovens, of which the following is a specification, the same being a division of application Serial No. 283,121, filed October 17, 1905.
This invention relates more particularly to the flue and baking chamber structure of a rotary bake oven, although the invention is not necessarily limited to use in connection with a rotary baking table or plane.
The object of the invention is to improve the construction and arrangement of flues above and below the baking chamber for the purpose of uniformly heating the chamber and utilizing the heated products of combustion to their fullest extent prior to their discharge from the oven structure.
Another object of the invention is to so arrange the flues that the heated air and gases may be directed either into or around the baking chamber, which affords a means for quickly heating the oven prior to the baking operation and thereafter maintaining its heated condition without bringing the heated gases into direct contact with the food being baked.
Another object of the invention is to so arrange the flues and passages that they may be readily cleaned out either from the front or rear, and the invention finally consists in the features of construction and combination of parts hereinafter described and claimed.
In the drawings Figure 1 is a sectional elevation from side to side of the oven showing the interior arrangement; Fig. 2 a sectional plan view of the lower flues taken on line 22 of Fig. 1; Fig. 3 a sectional plan view of the upper flues taken on line 33 of Fig. 1; Fig. 4 a longitudinal sectional elevation of the front of the oven; Fig. 5 a sectional elevation taken on line 55 of Fig. 4; and Fig. 6 a sectional elevation of the rear portion of the oven.
The oven is constructed of brick, is substantially cylindrical in shape, and is provided in its bottom with a series of air spaces 1, best shown in Fig. 1, which air spaces surround a solid central foundation 2 which supports the baking plane, and above the air spaces are arranged a series of lower flues, best shown in Fig. 2. The lower flues communicate with a fire chamber 3 having located thereina grate 4, behind which is a transversely extending bridge wall 5, and the fire box communicates with a central flue chamber 6 having straight parallel side walls 7 which terminate in curved inner flue walls 8, whose terminal ends 9 are separated from one another by a central partition wall 10 which terminates at its inner end in a central circular wall 11, in the middle of which is a circular recess 12 which forms a well for the step of the rotary shaft which carries the baking plane. Surrounding the inner flue walls 8 are curved intermediate flue walls 13 connected at their outer ends with straight partition walls 14 which are parallel with and separated from the central parti tion Wall 10. Outside of the intermediate flue walls 13 are outer curved partition walls 15 terminating at their forward end in straight partition walls 16, which are parallel with and separated from a pair of walls 17 which inclose the fire chamber and are in effect continuations of the walls 7 of the flue chamber. Outside of the outer flue walls 15 are the curved outer walls 18 of the oven, which arrangement of flue walls provides a series of curved flue passages, the intake openings for the passages being in staggered relation so as to provide a devious path of travel for the heated air and products of combustion from the fire chamber.
For the purpose of convenience, the several flue passages may be designated as the inner flue passage 19, the first intermediate flue passage 20, the second intermediate flue passage 21, and the outer flue passage 22. The outer flue passage terminates in a vertical flue 23 which connects with the upper flues, which are best shown in Fig. 3. The upper flues are of similar formation to the lower flues, and consist of outer flue passages 24, intermediate flue passages 25 and 26, and inner flue passages 27, the several passages being separated one from the other by means of concentric outer, intermediate and inner curved walls 28, 29, and 30, respectively. The upper flues on opposite sides of the oven are separated by means of a central partition wall 31 which extends from front to rear of the furnace, and is provided at its center with a rounded supporting post or column 32 through which passes the rotary shaft for the baking plane. The upper flues, like the lower,
are surrounded and inclosed by the outer closed walls 18 of the oven. The inner curved flue passages 27 terminate in forwardly extending straight passages 33 which connect with vertically extending passages 33 connecting with the discharge flue 34 which connects with the chimney for the oven. The lower flues are provided with forwardly extending inner clean-out passages 35 and outer clean-out passages 36, the lower flues being provided at their rear ends with inner clean-out passages 37 and outer clean-out passages 38, which arrangement allows the various passages to be cleaned for the purpose of removing soot or products jof combustion. The upper flue passages are likewise provided with forwardly extending inner clean-out passages 39 and outer passages 40, which passages are supplemented by inner clean-out passages 41 and outer clean-out passages 42 at the rear end of the furnace.
Leading from the outlet end 38 of the intermediate lower flue passages 21 are vertical passages 43 opening into the centrally located cylindrical baking chamber 44, and the passages 43 are adapted to be closed by means of slide dampers 45, which arrangement allows of a draft or circulation of heated air directly through the baking chamber if so desired. An outlet flue 46 leads from the forward side of the circular baking chamber and connects with the discharge flue 34, and said passage 46 can be opened and closed by means of a slide damper 47, which arrangement allows all of the products of combustion to pass either through the devious passage of the upper flues when the dampers 45 and 47 are closed or directly through the baking chamber when the dampers 45 and 47 are opened so that the heating of the oven can be regulated as desired.
Access is had to the interior of the fire chamber through an opening 48 in the front of the furnace, and access is had to the interior of the baking chamber through an opening 49 in the rear wall of the baking chamber. The various clean-out passages may be closed by means of doors 50 of any suitable character, and likewise the opening 48 may be closed by means of a door 51.
In use, fire is kindled in the grate and a draft is created through the lower flues and thence to the upper flues and through the chimney, causing the products of combustion to pass back and forth through the lower flues 19, 20, 21 and 22, and thence through the vertical passages 23 to the upper set of flues passing successively through the flues 24, 25, 26 and 27, from which latter flues the products of combustion are carried through the passages 33 and 33 and discharged into the chimney. The progress of the products of combustion back and forth through the flues serves to heat the floor and roof of the baking chamber very quickly preparatory to the baking operation. When it is desired to obtain a more direct draft, the dampers 45 controlling communication between the lower flues and the baking chamber are opened and the damper 47 controlling the draft from the baking chamber to the chimney is likewise opened, thereby establishing a direct draft through the baking chamber which serves to divert the progress of the heated air from the upper flues to the baking chamber, which serves to heat the baking chamber from within as well as from without, when so desired.
Although the oven, as shown and described, is constructed with particular reference to its use in connection with a rotarybaking plane, the same flue and chamber structure can, without any material modification, be used as an oven of the stationary type; and the method of directing the heated gases and products of combustion either into or around the bakingchamber is of general application, since the flue and chamber structure has no necessary dependence upon the particular method by which the bakery products are supported within the baking chamber.
What I regard as new and desire to secure by Letters Patent is:
1. In a bake oven, the combination of a circular baking chamber, a plurality of semi-circular, sinuous and connecting lower flues, a plurality of semi-circular, sinuous and connecting upper flues, a passage connecting each set of lower flues with the companion set of upper flues, a discharge flue connecting with the upper flues, passages connecting the lower flues with the baking chamber, a damper for controlling each of said last named passages, and a passage leading from the baking chamber to the discharge flue, substantially as described.
2. In a bake oven, the combination of a circular baking chamber, a plurality of semi-circular and sinuous lower heating flues beneath the floor of the baking chamber, a fire chamber in communication with the lower heating flues, a vertically extending passage leading from each set of lower heating flues through the floor of the baking chamber, a discharge flue in communication with the lower heating flues, a damper for controlling each vertical passage between the lower heating flues and the baking chamber, and a passage leading from the baking chamber to the discharge flue, substantially as described.
, 3. In a bake oven, the combination of a circular baking chamber, a plurality of semi-circular, sinuous 'and connecting lower heating flues beneath the floor of the baking chamber, a fire chamber in communication with the lower heating flues, a vertically extending passage leading from each set of lower heating flues through the floor of the baking chamber, a damper for controlling each of the last named passages, a plurality of semi-circular, sinuous and connecting upper heating flues above the roof of the baking chamber and in communication with the lower heating flues, a discharge flue connecting with the upper heating flues, and a discharge passage leading" from the baking chamber to the discharge flue, substantially as described,
4. In a bake oven, a baking chamber, a fire chamber, a central flue chamber leading from the fire chamber, a series of semi-circular and sinuous lower flues on each side of and in communication with the central flue chamber, located below the baking chamber and formed by concentric curved walls with adjoining flues ot' a series open at opposite ends to provide a sinuous passage for the products of combustion, a series of semi-circular and sinuous upper flues corresponding to and connecting with the lower flues and located above the baking chamber, vertical passages connecting the discharge end of each lower outer flue with the intake end of each upper outer flue, and a discharge fine in communication with each of the inner upper flues, substantially as described.
5. In a bake oven, a baking chamber,'a fire chamber, a central flue chamber leading from the fire chamber, a series of semi-circular and sinuous lower flues on each side of and in combination with the central flue chamber, located below the baking chamber and formed by concentric curved walls, With adjoining flues of a series open at opposite ends to provide a sinuous passage for the products of combustion, a series of semi-circular and sinuous upper flues corresponding to and coinciding with the lower series of flues and located above the baking chamber, a vertical passage connecting the discharge end of each lower outer flue-with the intake end of its companion upper outer flue, a discharge flue in communication with the inner upper flues, passages leading from the baking chamber to the discharge flue, and dampers for regulating the passage of the products of combustion through the flues, substantially as described.
6. In a bake oven, a circular baking chamber, a fire chamber, a central flue passage communicating with the fire chamber, concentric inner intermediate and outer lower flues located below the baking chamber on each side of the central flue passage and separated from each other by curved walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, a rear lower wall in line with the center of the fire chamber, concentric upper flues above the baking chamber, consisting of concentric inner, intermediate and outer flues corresponding to and coinciding with the lower flues and separated from each other by curved Walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, an upper center partition wall extending from front to rear of the oven, a passage connecting the discharge end of each outer lower flue with the intake end of the companion outer upper flue, a discharge flue, and a passage connecting the discharge end of each inner upper flue with the discharge flue, substantially as described.
' 7. In a bake oven, a circular baking chamber, a fire chamber, a central flue passage communicating with the fire chamber, concentric inner, intermediate and outer lower flues below the baking chamber on each side of the central flue passage and separated from each other by curved Walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, a rear lower wall in line with the center of the fire chamber, concentric upper flues above the baking chamber, consisting of concentric inner, intermediate and outer flues corresponding to and coinciding with the lower fines and separated from each other by curved Walls, with the intake ends of adjoining flues oppositely disposed to provide a sinuous passage, an upper center partition wall extending from front to rear of the oven, a passage connecting the discharge end of each outer lower flue with the intake end of the companion outer upper flue, a discharge flue, a passage connecting the discharge end of each inner upper flue with the discharge flue, a flue leading from the baking 4 chamber to the discharge flue, passages leading from the 1 lower fiues to the baking chamber, dampers for controlling the passage of the products of combustion through the flues and the baking chamber, substantially as described. FREDERICK R. BARNHEISEL.
Witnesses:
OSCAR W. BOND, WILLIAM H. AIKEN.
US352846A 1905-10-17 1907-01-18 Flue construction for bake-ovens. Expired - Lifetime US862046A (en)

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US28312105A US858053A (en) 1905-10-17 1905-10-17 Rotary baking-oven.
US352846A US862046A (en) 1905-10-17 1907-01-18 Flue construction for bake-ovens.

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