US3145705A

US3145705A - Furnace observation window

Info

Publication number: US3145705A
Application number: US233013A
Authority: US
Inventors: Lester D Bruce; Parmakian George
Original assignee: Riley Power Inc
Current assignee: Riley Power Inc
Priority date: 1962-10-25
Filing date: 1962-10-25
Publication date: 1964-08-25
Anticipated expiration: 1981-08-25

Description

INVENTORS.

M N 1w fiN UM RK M D R m ww ER 5 6 L. D. BRUCE ETAL FURNACE OBSERVATION WINDOW Filed Oct. 25, 1962 2% 'llll irlie-#4115 Aug. 25, 1964 FIG. 2

United States Patent 3,145,705 FURWACE OBSERVATION WINDOW Lester D. Bruce and George Parmakian, Worcester, Mass, assignors to Riley Stoker Corporation, Worcester, Mass., a corporation of Massachusetts Filed Oct. 25, 1962, Ser. No. 233,013 1 Claim. (Cl. 126193) This invention relates to a furnace observation window and, more particularly, to apparatus arranged to permit the operator of a stream generating unit or the like to examine the interior of the furnace to observe combustion conditions.

It is common practice in the manufatcure of steam generating units to provide a number of windows located at various points in the unit to permit the observation of conditions within the furnace. These windows are usually provided with a glass panel sometimes protected by a metal screen and sometimes tinted to cut down glare from the furnace. In any case, the radiation from the furnace is extremely great and the direct continuous impingement of such radiation on the glass and other elements in the window soon causes them to become inoperative. Furthermore, although air flow is often used to keep the window clean and to cool the glass, nevertheless, under ordinary furnace conditions a considerable amount of dust can accumulate inside of the window housing and it frequently becomes necessary to remove the cover and clean out the dust. This can usually only be done when the furnace is shut down and, since it is uneconomical to shut down the furnace only to clean observation widows, it is not always convenient to clean the windows when it seems to be necessary. These and other difficulties experienced with the prior art devices have been obviated in a novel manner.

It is, therefore, an outstanding object of the invention to provide a furnace observation window in which dust does not accumulate.

Another object of this invention is the provision of a furnace observation window in which glass and other delicate elements are protected from radiation when the window is not in use.

A further object of the present invention is the provision of a furnace observation window having a protective cover entirely contained within a gas-tight enclosure.

With these and other objects in view, .'as will be apparent to those skilled in the art, the invention resides in the combination of parts set forth in the specification and covered by the claims appended hereto.

The character of the invention, however, may be best understood by reference to one of its structural forms as illustrated by the accompanying drawings in which:

FIG. 1 is a front elevation view of a furnace observation window embodying the principles of the present invention;

FIG. 2 is a sectional view of the invention taken on the line II-II of FIG. 1;

FIG. 3 is a vertical sectional view of the invention taken on the line IIIIII of FIG. 1; and

FIG. 4 is an enlarged sectional view of a portion of the invention taken on the line IV-IV of FIG. 1.

The furnace observation window is shown as consisting of a main frame 1 of generally cylindrical form and a door 2 extending tranversely thereof. The door slides over an orifice frame 3 also located within the frame and held within the frame by machine screws 4. A cover 5 is bolted over the outside of the frame and a shaft 6 extends through the cover into the main frame for attachment to the door 2. A split locking ring 7 holds the shaft 6 within the bore of the door 2, and a 3,145,705 Patented Aug. 25, 1964 packing S underlies the locking ring to provide for rotation with a gas-tight construction.

A bushing 9 extends around the shaft 6, while a pin 10 extends through the shaft to lock it in place. An adjusting flange 11 is mounted on the shaft 6 at the outside to permit the adjustment of a torsion spring 12 which is located on the exterior of the shaft between the flange 11 and a handle 13 to bias the handle to the position in which the door 2 covers the orifice frame 3. The handle 13 is provided with a spring grip 14. A pin 15 extends through the handle 13 into the shaft 6 to lock the handle in place. A gasket 16 is located in the cover 5 and seals the glass 17 which is of a heatresistant type. The glass is locked in place by a spring clip glass retainer 18 held by lock washers 19 and machine screws 20. A screen 21 is held in place by a screen retainer ring 22 mounted on the exertior of the cover 5. A cover gasket 24 is provided between the cover and the frame 1 and the cover is held in place by bolts 25. Extending from the frame 1 is a pipe fitting 26 adapted to be connected to a source of pressure air.

The frame 1 is provided with an elongated tubular portion which is adapted to be mounted in the furnace wall and within this portion is mounted an insulating sleeve 27. The orifice frame 3 is provided with a bore 28 which is slightly smaller than the bore through the insulating sleeve. This orifice frame is provided with a shoulder having a radial surface 29 over which the plate-like door 2 slides as it moves about the axis of the shaft 6. Extending upwardly from the top of the frame is a secondary body 31 having a thin interior recess 32 in which the door resides entirely out of the passage defined by the bore 28.

The operation of the invention will now be readily understood in view of the above description. By operating the handle 13 to rotate the shaft 6 counterclockwise, as it is observed in FIG. 1, the door 2 will rotate about the axis of the shaft 6 and enter the recess 32 in the secondary body 31. At that time, the operator is free to look through the screen 21 through the glass 17 through the bore 28 and through the furnace wall into the interior thereof. A release of the handle 13 will cause the door 2 to fall back into place not only of the action of gravity but also because of the action of the torsion spring 12. At all times air enters the housing through the fitting 26 and flows into the furnace over the surface of the insulating sleeve 27, thus maintaining the observation window dust free. At the same time, when in operative position, the door 2 seals against the radial surface 29 and keeps the dust and heat away from the glass 17 and the surrounding areas.

It is obvious that minor changes may be made in the form and construction of the invention without departing from the material spirit thereof. It is not, however, desired to confine the invention to the exact form herein shown and described, but it is desired to include all such as properly come within the scope claimed.

The invention having been thus described, what is claimed as new and desired to secure by Letters Patent is:

A furnace observation window, comprising (a) a main frame of generally cylindrical form adapted to be mounted in an opening in the furnace Wall and having an axial passage extending therethrough,

(b) a cover carrying a glass plate mounted on the frame in gas-tight relationship over the outer end of the passage,

(0) an orifice plate mounted in the frame and having a bore extending therethrough, the plate having an axially-extending annular shoulder defining a surface extending radially outwardly from the bore,

3 4 (d) a plate-like door extending transversely of the (g) afin-like secondary body extending upwardly from passage and mounted in the body, the main frame transversely of the passage and (e) an axial pivot on which the door is mounted for having a thin recess for receiving the (1001' Whfifl sliding movement on an axial pivot over the said it is in the Said Second Positionradial surface of the shoulder from a first posi- 5 References Cited in the file of this patent tion in the passage to a second pos1t1on entirely removed from the passage 2908 254 i t 1 t l PATENTSO t 13 1959 means sn 1 in air under ressure to the frame .ango e a C inwardly fl goof, and P 2,926,658 Llgon Mar. 1, 1960 3,004,502 Hibner Oct. 17, 1961