US2227251A

US2227251A - Chimney for liquid fuel burners

Info

Publication number: US2227251A
Application number: US259770A
Authority: US
Inventors: Walter B Engh
Original assignee: Mantle Lamp Company of America
Current assignee: Mantle Lamp Company of America
Priority date: 1939-03-04
Filing date: 1939-03-04
Publication date: 1940-12-31
Anticipated expiration: 1957-12-31
Also published as: DE808767C

Description

Dec. 31, 1940. w. B. ENGH CHIIIN EY FOR LIQUID FUEL BURNERS Filed March 4, 1.939 4 Sheets-Sheet 1 mvmon WA'LTEEE- f/YGH. 6,

ATTORNEY.

31, w. B. ENGH ,25

CHIMNEY FOR LIQUID FUEL BURNERS Filed March 4, 1959 4 Sheets-Sheet 2 i nnnuunnnnnnn R h g 210 m nuunnnnunnu m1 7 INVENTOR. W41. TEE 5. E N 6H.

BY WW M ATTORNEY.

31, 1940-. w. B. ENGA 2,227,251

CHIMNEY FOR LIQUID FUEL BURNERS Filed March 4, 1939 4 Sheets- Sheet s .54 j j H 17 19 19" 20 Lida/l I I ii 2 h g gal 50:. T1: 5

.32 Z 12 I 2.9 I J6 i o Z5a. Z9 *26 INVENTOR. #2 27225. E/YGH ATTORNEY.

Dec. 31, 1940. w. B. ENGH 2,227,251

CHIMNEY FOR LIQUID FUEL BURNER S Filed March 4, 1959 4 Sheets-Sheet 4,

INVENTOR WflLTE/ZB. ENG?!" ATTORNEY.

Patented Dec. 31, 1940 UNITED STATES PATENT orrlcs Mantle Lamp Company of America,

Chicago,

111., a corporation of Illinois Application March 4, 1939, Serial No. 259,770

24 Claims.

This invention includes a chimney construction consisting of upper and lower sections for producing desired draft on a liquid fuel burner,

. so that the fuel may be burned in large quantity and with maximum efficiency, the chimney sections being spaced from each other vertically to produce a check-draft effect to facilitate the removal of the lower chimney section and burner when desired, and also to facilitate producing an oxidizing atmosphere in the upper chimney section to completely burn the oxidizable products of combustion .and any vagrant odors and gases that may find their way into the chimney.

One of the objects of the invention is to produce a two part chimney construction for use with a. liquid fuel burner, the upper section having fixed support and position excepting for general adjustment in assembling the device, and the lower section being carried by and having fixed relation to a burner movable horizontally to clean or recondition the burner, the upper end of the lower section and the lower end of the upper section having such relation that there is no interference between the adjacent ends of the chimney sections when the lower section is so moved from and into alignment with the upper section, yet at the same time preserving the desired chimney effect as a whole when the sections are in alignment with each other.

In space heating stoves where the products of combustion from the flame exhaust into a room or the space heated, objectionable odors are generally given off, whether the burner operates with a yellow flame or a blue flame. A further object of the invention is to provide a structure and operation practically eliminating these objectionable odors. A chimney draft somewhat greater than would normally be required for the burner is employed and then the excess draft is reduced to a normal amount so the burner will function properly, by the use of a check draft positioned above the flame of the burner, through which fresh air enters into the upper part of the chimney, and there mingles with the hot products of combustion and vagrant odoriferous gases escaping from the burner flame. A highly heated and oxidizing atmosphere is thus produced in the upper portion of the chimney which promotes a secondary combustion to destroy the objectionable gases which would otherwise escape from the chimney into the room.

A further object of the invention is to provide the adjacent ends of the chimney sections with a movable element or more specifically a ring,

carried by one of the sections and automatically cooperating with the other chimney section to secure the desired relationship between the adjacent ends of the chimney sections, and more specifically, where a check draft passage of definite extent is desired, to produce and maintain said passage substantially of the desired extent for changes in adjustment of the chimney sections due to use, and for misalignment of the chimney sections.

A further object of the invention is to construct and support the movable element or ring in a manner to materially increase the entry clearance below the upper chimney section, for the lower chimney section in moving the latter into alignment with the former, over the separation of the adjacent ends of said sections in use, by providing for automatically moving or tilting said member or ring to produce said increased entry clearance.

Generically, it is an object of the invention to make a chimney of the class described, in upper and lowersections substantially in alignment in use, the lower section being movable horizontally from and into said alignment, in which a movable element or more specifically .a ring, avoids interference during said horizontal movement and effects substantially constant chimney action for small misalignments of the chimney sections and where desired, provides a check draft passage of definite amount into the chimney and maintains said passage of the desired amount for small changes in the relation of the chimney sections either axially or laterally from their optimum relation, which member or ring may also by its movement increase the entry clearance of the lower chimney section when moving it into alignment with the upper chimney section.

The invention will be best understood by reference to the accompanying drawings illustrating a preferred embodiment thereof, in which:

Fig. 1 illustrates an enclosed stove equipped with the chimney construction of the invention, in front elevation, the stove being provided with a removable cover which is shown in place in this figure.

Fig. 2 shows in side elevation the structure illustrated in Fig. 1.

Fig. 3 is a top view of the device with the removable cover in place,

Fig. 4 is a top view of the device with the cover removed,

Fig. 5 is a vertical sectional view through the device, taken along the line 55 in Fig. 1,

Figs. 6, 7 and 8 are horizontal sectional views through the device, taken respectively along the lines 6-6, 1-! and 8-8 in Fi 1,

Fig. 9 shows in an enlarged view similar to Fig. 5, the upper portion of the lower chimney section and the adjacent portion of the upper chimney section,

Fig. 10 shows in a view similar to Fig. 9, the relation of the movable device on the upper chimney section, when the lower chimney section is removed from alignment with the upper chimney section, and

Fig. 11 is a horizontal sectional view through the structure taken along the line H-ll in Fig. 9.

Similar numerals refer throughout the several views.

As shown in Figs. 1 and 2, the illustrated structure consists of a sheet metal casing l0 having front, back and side walls in which vertical apertures II are formed to permit thefiow of airinto orfrom the casing, as may be required during the operation of the burner. In the lower portion of the front wall of the casing a door i2 is provided which is mounted on pivotal supports l3 and M, the casing being supported on base portions 15. The casing is provided with, a removable sheet metal cover l6 provided with front, back and side walls containing perforations H to permit the egress of the hot gases resulting from the operation of the device. As shown in Fig. 3, the cover [8 is pro vided in its top surface with perforations l8 which also permit ,the egress of the hot gases resulting from the operation of the device. As

to similar parts .shown in Fig. 4, the upper end of the casing I0 below the cover I6 is provided with a top wall 1 l9 supporting in its central portion a grating 20 for cooking purposes,,so that with the cover l6 removed, the device may be used as a cooking stove, whereas if it is to be used as a heating stove, the cover 16 is preferably put in place .to give the device a better appearance and provide for a more effective distribution of the heated gases than is possible with the arrangement of the device which is most effective for cooking purposes. The top wall I9 is provided with apertures 2i around the grating 20 to permit the escape of the heated air in the casing around the chimney structure.

As shown in Fig. 5, the casing I 0 supports centrally therein and in its upper portion, an upper chimney section 22, so that the said chimney section is in alignment with the grating 20. The lower end portion of the chimney section 22 is engaged by a clamping band 23 provided, as more clearly shown in' Fig. 6, with arms 24 supported at their outer ends by the side walls of the casing it. The clamping ring 23 is held in place against the chimney section 22 by clamping screws as indicated, which screws are connected with the lower ends of inclined bracing rods 25 extending to the upper outer portion of the casing to which they are secured, as indicated in Fig. 1. In this manner the upper chimney section 22 receives fixed support at its lower end, from the casing l8, and in assembling the parts, the chimney section may be moved vertically in the clamping ring 23 to properly locate its lower end relatively to the upper end of the lower chimney section: 26, and then the section '22 may be rigidly clamped in that position.

This imparts a fixed support to the lower end of the chimney section 22 adjacent the checkdraft passage, so that any expansion or con .secured, for example by spot welding.

traction of the lower chimney section 22, which is due to heating or cooling the same, results in vertical movement of the upper end of the chimney section relatively to the casing. To permit this relative movement, the top wall IQ of the casing is provided with wings 27 extending downwardly from the edge of the opening made to receive the grating 28, so that the lower portions of said wings lightly engage the outer surface of the upper end portion of the chimney section 22, to hold said upper end portion in vertical position, and at the same time to permit expansion or contraction vertically or said upper end portion.

The lower portion of the casing ii] is provided with horizontal channel-shaped guideways 28 to engage the side portions of a liquid fuel tank or reservoir 29, which carries a burner 35 to the upper portion 36a of which the lower edge portion of the lower chimney section 26 is rigidly The rear ends of the guideway members 28 have secured to them a cross-bar 28a to engage the tank 29 when it is moved rearwardly sufficiently to bring the chimney sections into alignment with each other. The chimney section 25 is provided at its lower edge as more clearly shownin Fig. 9, with an outwardly extending flange 26a ,pro-

.vided with spacing lugs 261) which produce a fixed separation between the flange 25a and a horizontal flange 36b constituting a part of the burner structure. This insures the admission of a definite amount of air to the burner under the lower edge portion of the chimney section 26 which passes upwardly in the chimney sections around the flame produced by the burner. The burner flange 35b is preferably rigidly secured to the upper portion 36a of the burner shell, for example, by spot welding. To give the lower chimney section 26 a fixed position relatively to the burner, said lower chimney section is preferably rigidly secured to the burner shell, for example, by spot welding the lugs 25b of the lower chimney section to the burner flange 36b.

The chimney section 26 is prefera-bly of sheet metal and is provided at its upper edge with an integral and inwardly extending horizontal flange 260 on which lugs 36a connected with the upper chimney section 22, rest. The upper chimney section 22 adjacent its lower end is provided with inwardly extending pivots 3| extending through short vertical clearance slots 3% formed in a tubular device 38 carried by the lower end portion of the chimney section 22. The device 383 is provided with a horizontal flange portion 300 at its lower end, which is preferably integral with the tubular portion of the device and extends outwardly and horizontally therefrom so that it may occupy a position substantially parallel with the upper surface of the flange 250. The lugs 30a are formed downwardly from the flange 360. As shown in Fig. 11, the pivots 3| are slightly in front of the diameter of the lower chimney section which extends from side to side thereof, as a result of which the major portion of the weight of the movable device 36 is back of its pivotal supports, so that when the lower chimney section 26 is moved from alignment with the upper chimney section 22, as illustrated in Fig. 10, the front or entry portion of the flange 360 is raised substantially above the position it occupies during the operation of the device, thereby affording ample entry clearance for the lower chimney section 26, so that inter- --ference or catching and injury of the parts, is

check-draft effect is practically impossible when the lower chimney section is moved towards the rear of the structure in moving the reservoir 29 into operative position in the casing and at the same time moving the lower chimney section 26 substantially into alignment with the upper chimney section 22. As a result of the construction described however, when the lower chimney section has been moved under the movable device 30 substantially half way to its operating position, the movable device rests on the flange 260, the lugs 30a as illustrated in Fig. 11 being so disposed that they are always above some portion of the flange 260, as the movement of the lower chimney section 26 is completed to its operating position. It will be noted that there is a substantial clearance space between the lower end of the chimney section 22 and the flange 300, to permit the substantial tilting of the movable member 30 illustrated in Fig. 10, when the lower chimney section 26 is removed from alignment with the upper chimney section 22.

The lower chimney section 26 is provided in its front wall with a sight opening 26d which is closed by a sheet of transparent heat-resistant material 32, for example mica, which is held in place by a frame 33 secured to the chimney section 26, to afford a visible indication of the operation of the burner of the device.

As shown in Fig. 5, the cover It is preferably provided with a baffle plate 34 over the upper end of the chimney section 22, to distribute the highly heated gases delivered from the upper end of said chimney section.

The cooperating parts at the upper end of the lower chimney section 26, determine a checkdraft passageway 35 between the flange 26c and the flange 300, the vertical extent of which passageway is determined by the amount of projection of the lugs 30a from the flange 300. To permit the tilting action illustrated in Fig. 10, the tubular portion of the movable device 30 must be a correspondingly loose fit in the lower portion of the upper chimney section 22, which results in a small amount of air flow into the upper chimney section 22 between its lower end portion and the outer surface of the tubular device 30, which, however, is substantially constant and is compensated for by so selecting the vertical height of the passageway 35 that the total of the desired amount.

The movable device 30 thus not only provides a construction which makes the entry of the lower chimney section to its operative position a simple matter, requiring no thought or attention from the operator, but it also where desired, automatically insures a check-draft effect of definite amount, which is found to be effective in connection with securing complete combustion of the fuel, of the incomplete products of combustion, and of vagrant and noxious fumes that may find their way into the chimney. This accomplishes a two-fold effect, (1) it results in complete combustion of the liquid fuel and therefore the production of the maximum possible quantity of heat for a given quantity of fuel, and (2) it discharges heated gases from the device which are not in any way unpleasant or offensive. In cases where the check-draft is small, or is not desired, the lugs 30a may be correspondingly small, or may be omitted.

While I have shown my invention in the particular embodiment above described, it is understood that I do not limit myself thereto as I may.

employ equivalents thereof without departing from the scope of the appended claims.

Having thus described my invention, what I claim is:

1. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, and tilting means carried by one of said adjacent chimney end portions substantially increasing the entry clearance vertically between said chimney end portions when said lower chim-' ney section is removed from chimney section.

2. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, and tilting means carried by one of said adjacent chimney end portions substantially increasing the entry clearance vertically between said chimney end portions when said lower chimney section is removed from below said upper chimney section, said tilting means having vertically movable connection with the chimney portion supporting it maintaining a fixed effective check-draft spacing between said adjacent end portions for variances in vertical spacing of said upper chimney section from said burner.

3. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater weight back of than in front of said pivotal connections tending to tilt the front portion of said ring upwardly, the upper end portion of said lower chimney section having engagement with and spaced from said ring to form said check-draft passageway.

4. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, 'a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater Weight back below said upper of than in front of said pivotal connections tending to tilt the front portion of said ring upwardly, the upper end portion of said lower chimney section having engagement with and spaced from said ring to form said check-draft passageway, said ring having downwardly extending lugs determining the spacing of said ring from said lower chimney section.

5. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater weight back of than in front of said pivotal connections tending to tilt the front portion of said ring upwardly, said ring having a horizontal flange cooperating with the upper end of said lower chimney section to form said check-draft passageway.

6. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater weight back of than in front of said pivotal connections tending to tilt the front portion of said ring upwardly, said ring having a horizontal flange cooperating with the upper end of said lower chimney section to form said check-draft passageway, said flange having downwardly extending lugs determining the spacing of said flange from said lower chimney section.

7. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater weight back of than in front of said pivotal connections tending to tilt the front portion of said ring upwardly, said ring having a first horizontal flange, and said lower chimney section having a second horizontal flange spaced from and cooperating with said first flange to form said check-draft passageway.

8. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater weight back of than in front of said pivotal connections tending to tilt the front portion of said ring upwardly, said ring having a first horizontal flange, and said lower chimney section having a second horizontal flange spaced from and cooperating with said first flange to form said check-draft passageway, one of said flanges having projecting lugs determining the spacing of said flanges from each other.

9. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater weight back of than in front of aid pivotal connections tending to tilt the front portion of said ring upwardly, the upper end portion of said lower chimney section having engagement with and spaced from said ring to form said check-draft passageway, said pivotal connections being loosely fitted vertically, whereby said ring is movable vertically relatively to said upper chimney section.

10. A device for burning liquid fuel including in combination a fuel reservoir, a burner carried by said reservoir, a lower chimney section carried by said burner, an upper chimney section having fixed support, means supporting said reservoir for horizontal movement, whereby said lower chimney section may be moved into and from alignment with said upper chimney section, there being a check-draft passageway into the chimney at the upper end of said lower chimney section, a ring loosely fitting the lower end of said upper chimney section, and pivotal connections between said ring and said upper chimney section, said ring having greater weight back of than in front of said pivotal connections tending to tilt the front portion of said ring upwardly, said ring having a first horizontal flange, and said lower chimney section having a second horizontal flange spaced from and cooperating with said first flange to form said check-draft passageway, one of said flanges having projecting lugs determining the spacing of said flange-s fro-m each other, said pivotal connections being loosely fitted vertically, whereby said ring is movable vertically relatively to said upper chimney section.

11. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section and forming a check-draft passageway between said sections when said sections are substantially in alignment with each other, and means maintaining said passageway substantially constant for different vertical positions of said upper section relatively to said lower section, said means including a ring carried by and having vertical movement relatively to said upper section, said ring having vertically. loose pivotal connection with said upper section in front of the center of gravity of said ring tending to tilt the front portion of said ring upwardly to increase the entry clearance of said lower section.

12. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section and forming a check-draft passageway between said sections when said sections are substantially in alignment with each other, and means maintaining said passageway substantially constant for different vertical positions of said upper section relatively to said lower section, said means including a ring carried by and having vertical movement relatively to said upper section, said ring having a first horizontal flange and said lower section having a second horizontal flange, said flanges cooperating to define said check-draft passageway, said ring having vertically loose pivotal connection with said upper section in front of the center of gravity of said ring tending to tilt the front portion of said ring upwardly to increase the entry clearance of said lower section.

13. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance forsaid lower chimney section is substantially increased when said lower chimney section is moved from below said upper chimney section.

14. In combination, an upper chimney section having fixed position, a lower chimney section movable horizon-tally into and from alignment with said upperchimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance for said lower chimney section is substantially increased when said lower chimney section is moved from below said upper chimney section, said lower chimney section having a flange extending horizontally from its upper end for cooperation with said ring.

15. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance for said lower chimney section is substantially increased when said lower chimney section is moved from below said upper chimney section, said ring having a flange extending horizontally from its lower end for cooperation with said lower chimney section.

16. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance for said lower chimney section is substantially increased when said lower chimney section is moved from below said upper chimney section, said ring having a flange extending horizontally from its lower end, and said lower chimney section having a flange extending horizontally from its upper end for cooperation with said ring flange 17. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance for said lower chimney section is substantiallyincreased when said lower chimney section is moved from below said upper chimney section, said pivotal connections being loosely connected vertically whereby said ring is capable of limited vertical movement relatively to said upper chimney section.

18. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance for said lower chimney section is substantially increased when said lower chimney section is moved from below said upper chimney section, said pivotal connections being loosely connected vertically whereby'said ring is capable of limited vertical movement relatively to said upper chimney section, said lower chimney section having a flange extending horizontally from its upper end for cooperation with said ring.

19. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance for said lower chimney section is substantially increased when said lower chimney section is moved from below said upper chimney section, said pivotal connections being loosely connectedlverticaliy whereby said ring is capable of limitedlvertical movement relatively to said upper chimneysection, said ring having a flange extending horizontally from its lower end for cooperation with said lower chimney section.

20. In combination, an upper chimney section having fixed position, a lower chimney section movable horizontally into and from alignment with said upper chimney section, and a ring pivotally connected with the lower end portion of said upper chimney section and extending below the lower end of said upper chimney section, the pivotal connection of said ring being laterally displaced from the center of gravity of said ring and towards. the entry position of said lower chimney section, whereby said ring is tilted and the entry clearance for said lower chimney section is substantially increased when said lower chimney section is moved from below said upper chimney section, said pivotal connections being loosely connected vertically whereby said ring is capable of limited vertical movement relativelyto said upper chimney section,lsaid ring having a flange extending horizontally from its lower end, and said lower chimney section having a fiange extending horizontally from its upper end for'cooperation with said ring flange.

21'. In combination, an upper chimney section having fixed position, a lower chimney section confined to horizontal movement into and from alignment with said upper chimney section, and amovable sleeve substantially coaxial with and adjacent the end of one of said chimney sections and actuated by engagement with the other of said chimney sections during horizontal movement of said lower chimney section to provide a check-draft passageway of predetermined size into the chimney,

22.'In combination, an upper chimney section havinglfixed position, ..a lower chimneysectioni' confinedto horizontal movement into and from alignment with said upper. :chimneyjsectio'n, and

a movable sleeve. substantially coaxialwith and 1 adjacent the end of one of said chimney sections L.

and actuated by engagement with the. other "of said chimney sections during horizontal movement of said lower chimney section to-provide a check-draft passageway of predetermined size Into the chimney, said sleeve being mounted for free movement vertically to compensate for mal adjustment of the chimney sections.

23.v In combination, an upper chimney section having fixed position, a lower chimney section" confined to horizontal movement into and from alignment with said upper chimney section, and

a movable sleeve substantially coaxial with and adjacent the endof one of said chimney sections 7 and actuated by engagement with the other. of said chimney section's during horizontalmo-vement of said lower chimney section to provide a check-draft passageway of. predetermined size into the chimney, said sleeve having spacing into the chimney, said sleeve and said other chimney section having horizontally extending flanges cooperating to establish said check-draft passageway.

WALTER B. ENGH.