US2891567A - Reversing valve mechanism - Google Patents

Description

June 23, 1959 E. W. POTTMEYER REVERSING VALVE MECHANISM I 2 Shee ts-Shaet 1 Filed Nov. 25, 1955 June 23, 1959 E. w. POTTMEYER mavsnsmc VALVE MECHANISM Filed Nov. 25. 1955 2 Sheets-Sheet 2 INVENTOR Edward W. Poflmeyer United States Patent REVERSING VALVE MECHANISM Edward W. Pottmeyer, Pittsburgh, Pa., assignor to Blaw- Knox Company, Pittsburgh, Pa., a corporation of Delaware Application November 25, 1955, Serial No. 548,802

10 Claims. (Cl. 137-310) This invention relates to a reversing valve mechanism for metallurgical furnaces or the like. More particularly, my invention pertains to such mechanism in which a valve is moved horizontally relative to a port.

Various prior practices have been provided inclusive, for example, of reversing valves which swing about a pivot as illustrated in my United States Patent No. 2,525,826 and of reversing valves which are moved vertically as shown in my United States Patent No. 2,621,049. In the case, for example, of prior vertically movable valves, extensive equipment was required in the form of sheaves, brackets, drive cables and remote operators, much of which could not, moreover, be preassembled.

The instant invention is for a different kind of reversing valve and mechanism in which the valve is moved horizontally. Thereby, devices made in accordance with my present invention have a low headroom characteristic, permit maximal port opening sizes and facilitate work on furnaces where my present invention may be installed including the making of damper changing easier. The instant invention can be relatively wholly shop assembled and transported as a substantially self-contained unit.

Other objects and advantages: of my invention will be apparent from the following description and from the drawings, which are illustrative only, in which:

Figure 1 is a plan view with certain parts broken away to illustrate details of. one embodiment of. my invention utilized in a regenerative furnace for changing the direction of flow of combustion air and Waste gases respectively to and from different ends of such furnace;

Figure 2 is, a view taken along line II-=-II of Figure 1;

Figure 3' is a view taken along line II'I1I'II of Figure 2;

Figure 4 is a view of the structure shown in Figure 3 taken along, line Iv -IV of Figure 3;

Figure 5 is a view taken along line V'-V of. Figure 3; and

Figure 6 is a view of a modified arrangement of my invention in a regenerative furnace.

Referring to Figures 1 to 5 of the drawings, one form of my invention is illustratedLas a reversing valvemechanism unit 10 set in place in a regenerative furnace 11. Furnace 11 is provided with a combustion air inlet 12 supplied with combustion air by a fanor blower when the furnace is operating. A duct 13- is connected to inlet 12 and communicates with a plenum chamber 14 below a deck .15 in unit 10; The rear side of plenum 1 4 is also enclosed in the illustrated embodiment by a refractory wall 27 extendingbetween the central pillars 28 of the ported valve seats 29 in unit 10. The combustion air from chamber 14 flows to furnace duct 25 or 26, as the case may be, depending upon the positioning of the valves of unit 10.

Deck 15' is provided with an auxiliary air opening 15 surrounded by a coaming 16 normally closed by a door 17. Door 17 can be raised or lowered by depressing or raising, respectively,'.the. arms 18 which are pivoted at 19 to brackets 20 fastened to the, front cross beam 21 of unit 10. The lower ends. 22 of arms 18 are fastened to the top 2,891,567 Patented June 23, 1959 of door 17. A threaded rod 23 is connected to brackets 20 at its lower end for rotatable but not axial movement relative thereto. Rod 23 may be turned by a squared end 24 which engages a nut held by arms 18 to produce upward or downward movement as desired of arms 18. As stated, door 17 is normally closed but in the event of failure of the combustion air fan, a socket wrench may be employed to turn squared end 24 and thereby the threaded rod 23 to open door 17 and allow combustion air to flow into the plenum chamber 14 under the eifect of the furnace draft conditions. The extent of such opening of door 17 can be utilized in the manner of a damper to regulate the combustion air so supplied under auxiliary or emergency conditions as when there is a power failure.

Two valve seats 29 are employed in unit 10. Such seats 29 there shown have parallel horizontal edges and planes which converge in an upward direction as shown in Figure 2 for the embodiment so illustrated. Each seat 29 is provided with a port 30 and a port 31 in side-byside relation. Both ports 30 are at the front end of seats 29 in the embodiment in Figures 1 to 5 and ports 30 are alternatively used for the admission of combustion air respectively to duct 25 and to duct 26. Both ports 31 in seats 29 are to the rear of wall 27 and provide an exhaust port for waste gases alternatively from duct 25' and duct 26 depending upon which such port 31 is open. Such waste gases enter chamber 32 and flow from thence into a stack duct 33 past a normally open damper 34. A stack is connected to stack duct 33.

The top of chamber 32 is covered by a refractory roof 35 extending rearwardly from wall 27 between the respective valve seats 29. While unit 10 is being described in connection with its use for controlling the flow of combustion air and waste gases, it will be understood that many other uses of my devices and parts thereof may be made and that my invention may take various forms and be used in different arrangements including those in'which but a single valve seat and valve are utilized.

The surrounds of ports 30 and 31 in each valve seat 29 may have passages 36 extending therethrough for the circulation of cooling gas or liquid supplied through, for example, an external pipe 37 and conducted away through an external pipe 38. The planar valve face 39 of each seat 29 is machined flat and engaged by an uninterrupted peripheral machined edge 40 of its respective valve 41. The inward and upward slope of'the seats 29 causes the valves 41 to press against face 39 for effective valving.

The valves 41 are rectangular and of sufiicient size so that, in unit 10, when one valve 41 overlies the port 30 on its side so as to close it, the other valve 41 will overlie the port 31 on the other side and close that port. The result is, of course, that combustion air will flow through the open port 30 in the one direction while waste gas coming from the other direction will exit through the open port 31 on that side. When the position of the valves 41 is reversed, waste gases will exhaust from the first-mentioned side and combustion air will flow into the second-mentioned side of the furnace. In the position of the valves 41 shown in Figures 1 and 2, air is entering duct 26 and waste gases are being exhausted from duct 25 through the left-hand port 31 as viewed in Figure 1.

Each valve 41 is provided with spaced front and. back faces 42' and 43 respectively and is closed around the sides by side wall 44 leaving an enclosed space therein which, in operation in high temperature furnaces, is cooled by the circulation therethrough of a cooling gas or liquid; The top' of each valve 41 is provided with longitudinally spaced pairs of cars 45 between which straps 46': extend for support connection to the ears by pins 47 to support such valves.

A rib 48 may be provided along the top of the valve seats 29 to which a longitudinal bracket 49 is aflixed. Bracket 49 in turn supports a longitudinal track plate 59 extending substantially the length of the path of the travel of each valve 41 on its valve seat 29. n the other side of each valve 41, there is a channel member 51 fastened to end plates 52 on each side at the respective ends of the respective valve seats 29. Front beam 21 and intermediate beam 53 connecting the backs of the pillars 23 connect the respective valve seats 29 rigidly together and enable unit in substantial measure to be prcasscmbled in a shop, if desired, and shipped to the site of use as a unit.

A longitudinally extending track angle 54 is rigidly aflixed to channel 51 in such position that the lower edge of angle 54 and the upper edge of plate 50 define a planar track perpendicular to face 39 and a longitudinal slot 55 extending along the operative length of the seats 29. The straps 46 extend upwardly through slot 55 on each side of unit 16 and are fastened as by welding to a longitudinally extending carriage 56 shown as being of channel form in end profile. Axles 57 are fastened to the sides of carriage 56 and act as the journals for rollers 58 at the respective ends of the carriage, the rollers being movable longitudinally along the track formed by track angle 54 and track plate 50.

An upstanding lug eye 59 is welded to the upper side of carriage 56 in the center thereof for engagement by a lifting hook or chain whenever a valve is to be changed or removed, as described below. Base plates 60 are fastened at opposite ends of the slots 55 and are in the same plane therewith. A sprocket bearing 61 is secured to each plate 60 and has a sprocket 62 keyed to each of the bearing shafts in 61.

An endless chain, preferably in the form of a roller chain 63, engages the respective sprockets 62 on each side of unit 10 immediately above the valves and valve seats. The ends of chain 63 on each side are connected by an adjustable turnbuckle 64, which acts as a link which always remains in the upper reach of the chain. Turnbuckle 64- has lock nut provisions therein for regulating the appropriate length and tension of chain 63. Chain 63, as shown, is therefore in two portions, the ends thereof remote from turnbuckle 64 being pivotally connected to the respective ends of carriage 56 by pins 65. Thus, carriage 56 also acts as a link which always remains in the lower reach of chain 63 and on track 50-54.

As the drive sprocket 62 is rotated on each side, the corresponding carriage 56 in unit 10 will roll on its track and cause its valve 41 to slide horizontally along face 39 from a position over one port to a position overlying the other port in its valve seat 29 and vice versa when the direction of movement of chain 63 is reversed. As stated, turnbuckle 64 remains in the upper part of chain 63 between sprockets 62 and carriage 56 remains on the track Sill-54.

Cooling fluid may be supplied to the interior of each valve 41 and circulated therethrough by a pair of pipes 66, one of which is for admission and the other of which is for discharge. Such pipes may extend upwardly in longitudinal alignment with straps 46 and pass upwardly through holes in carriage 56 whence the pipes are fitted with couplings 67 for connection to flexible pipes 68 through which such fluid circulation takes place, one such set being provided for the valve 41 on each side of unit It). The pipes 66, as shown, are positioned above roof 35 and communicate with a source of such cooling fluid.

The working parts of my device above the top of each valve 41 including chain 63, carriage 56 and sprockets 62 are protected under severe heat conditions by asbestos composition strips which serve to substantially close the slot 55 regardless of the position of the carriage 56 along such slot. For that purpose, the outer side of those portions of chain 63 which move into the lower reach be- 4 tween the sprockets 62 is provided with transverse bars 69 fastened thereto. The bars 69 are wide enough to span the width of slot 55. An asbestos composition strip 74 of a flexible nature and suitable length and thickness is fastened preferably to the end ones 71 of the bars 69 which are adjacent to the respective ends of carriage 56. The other ends of the strips 78) remote from carriage 56 are likewise fastened to the respective adjacent bar 69. Such fastening may be made by means of rivets or bolts having countersunk heads so that no part thereof projects beyond the outer side of the asbestos strips 70. Hence, regardless of the position of carriage 56 along its track, some part of one or both of the strips will overlie slot 55 except beneath carriage 56. The bars 69 will keep such strips 70 flat and gently pressed against the sides of slot 54 to cover and substantially close the same without excessive pressure or friction.

in like manner, a suflicient length and thickness of asbestos compositon strip 72 is fastened by its ends to the underside of carriage 56 to form, in effect, with strips 79, a continuous asbestos strip overlying slot 55 along its whole length. Some slack may be left in strip 72 so it will engage track portions 54 and 5t and cover slot 55 substantially over the whole of the length of the underside of carriage 56. Openings are provided in strip 72 for the passage therethrough of straps 46 and pipes 66. Thus, the slot 55 is relatively sealed and the escape of gas and heat therethrough from chamber 14 or chamber 32 is inhibited. Further, such covering of slot 55 inhibits infiltration of air from the outside into chamber 32 and the furnace.

The sprocket 62 which drives the respective chain 63 and carriage 56 on each side is at the front end of unit 10 in the embodiment being described. The drive unit, which may be preassembled in the unit if desired, comprises a reversible motor 74, such as an electric motor. The motor in turn drives a gear reducer 75 through a flexible coupling 76. Reducer 75 may also be driven through flexible coupling 77 by a manual gear drive 78. Drive 78 may use bevel gears and be actuated by rotating a squared end 78 operatively connected thereto, by means of a socket wrench. Thus, Whenever there is a power failure, if it is desired to continue the reversing movement of the valves by hand, provision is made in the illustrated embodiment for so doing. The output shaft 79 from reducer 75 is connected to the sprocket shaft of drive sprocket 62 by an intermediate shaft 80 to which a pinion sprocket 811 is keyed. Pinion sprocket 81 drives a switch sprocket 82 by means of an endless chain 83, the sprocket 82 being keyed to a cam shaft in a limit switch 84. There is a similar motor drive and limit switch assembly on each side of unit 116 often so regulated for automatic operation that, as described above, when valve 41 on one side is over port 31, the valve 41 on the other side will be over its respective port 30, and, vice versa. The limits of movement of the respective valves 41 can be set by the respective limit switches 84 so that as each carriage and valve comes to the end of its travel in one direction, motor 74 will be reversed and condition the members for travel in the other direction with the timing and sequence desired for the particular furnace operation desired.

A sheet metal hood 85 may be fastened to channel 511 and end plates 52 to cover the carriage and chain elements on each side of unit 110. If it is desired to remove a valve 41, valve 41 is centrally placed adjacent pillar 28. The hood 85 is removed whereupon the respective turnbuckle 64 on that side is opened and the chain 63 disconnected and taken away from carriage 56. Then track plate 50 and track angle 54 may be loosened from. their respective supports and track plate 50 removed. A chain attached to a crane hook is then passed through eye 59 and upon lifting, eye 59 will lift the carriage 56, the valve 41 connected thereto and the corresponding track angle 54. As the of carriage 56 begins,

the pair of rollers 58 on the track angle side of slot 55 will catch beneath the brackets 86 attached to angle 54 and cause it. tobe lifted and removed at the same time that. valve 41 is removed. A reversal of these steps will reposition a valve 41 and the removed parts on that side for continued operation of the unit and the furnace in which it is installed.

A modified arragement utilizing my invention is illustrated in Figure 6. Therein, in a regenerative furnace 109, for example, combustion air may be supplied through a pipe 100 and pass through a reversing valve 101 which may be made in accordance with my copending United States application for patent, Serial No. 202,846, filed December 27, 1950, now Patent No. 2,767,738. The two outlet ends of valve 101 are connected respectively by pipes 103 and 104 to furnace ducts 105' and 106 respectively on the two sides of the furnace. A valve seat 107 and valve 108 made in accordance with my present invention may be employed, corresponding to structure, inclusive of means for moving valve, to structure on one side of the above-described unit 10. In this modification, it will be noted that but a single valve, seat 107 with two ports therein and but a single valve 108 is required for furnace 109. As shown, the side of the furnace to which duct 105 is connected is on an air cyclewhile waste gases from the furnace are exiting through duct 106 and uncovered. port 110 to stack 111 through open damper 112. Such flows are shown by the arrows. Conversely, when furnace 109 is reversed, valve disc 102 closes the air port to duct 105 and opens the air port through pipe 104 to duct 106 at the same time that valve- 108 is moved to close port 110 and open port 113 so that waste gas now isexhausted through duct 105, port 113 and stack 111 in the other step of such a reversing, cycle.

Various modifications may be made in various elements and parts of my invention and in uses to which my invention may beput, whether in connection with reversing furnaces or non-reversing furnaces 01: for other purposes, without departing from the spirit of'my invention or the scope of the appended claims.

I claim:

1. In a valve mechanism, apparatus comprising, in combination, a horizontally extending valve seat, said seat having a flat face on which a valve is adapted to slide to and fro, said seat having a port therethrough, a valve in contact with said face and adapted to open and close said port, a track having spaced portions defining a slot extending alongside the top of said seat in rigid connection therewith, a carriage movable back and forth along said track, means extending through said slot for supportably connecting said valve to said carriage, cable means connected to said carriage to draw it back and forth on said track, and means for substantially closing said slot irrespective of the position of said carriage on said track.

2. In a valve mechanism, apparatus comprising, in combination, a longitudinally extending valve seat, said seat having a fiat face on which a valve is adapted to slide back and forth, said face being generally upright relative to a horizontal plane, said seat having a port therethrough, a valve in contact with said face and adapted to cover said port when overlying the same, a track extending generally along the top of the path of movement of said valve, said track being connected to said valve seat, a carriage movable back and forth along said track, means for supporting said valve in depending relation from said carriage, and a member connected to said carriage to draw it back and forth on said track to cause said valve to cover and uncover said port, said member being on the side of said track away from said seat.

3. In a valve mechanism, apparatus comprising in combination, a longitudinally extending valve seat, said seat having a flat face on which a valve is adapted to be moved, said face being at an angle to a horizontal plane, said seat having a port, a valve in contact with said face and adapted selectively to cover and uncover said port, atrack extending generally along above the path of movement. of said valve, a carriage movable along said track, means for suspending said valve from said carriage for movement therewith, and a member connected to said carriage. to move it along said track to cause said valve selectively to cover and uncover said port, said member being o-n thevside of said track away from said seat.

4. In a reversing valve mechanism, apparatus comprising, in combination, a pair of horizontally extending valve seats, in spaced relation, said valve seats being upwardly convergent, transverse beams rigidly connected to said valve seats, a pair of ports in side-by-side relation extending through said valve seats, the front and back of the ports in each of said valve seats being in transverse registry, said valve seats having a machined planar valve engagement face on the respective outer sides thereof, a hollow valve adapted to be slid horizontally along each of said valve seats while in engagement with the respective faces thereof, a track rigidly connected to each of said valve seats and projecting above the path of movement of the valve on said seat, said track having longitudinally extending spaced portions defining a slot between such portions, a carriage movable on said track for each valve seat above said slot, a depending strap connected to said carriage and extending downwardly through said slot, said valve being connected to said strap below said slot to support said valve for movement back and forth in engagement with its respective valve seat face, an endless cable mounted in a plane normal to said track-and generally in alignment with said slot to move said carriage back and forth, a heatresistant flexible belt connected to the outside of said cable andlthe underside of said carriage to maintain said slotsubstantially closed. by means of said, belt irrespective of the position of said carriage along said track, reversibl e means for driving said cable, and further means extending through said slot for circulating cooling fluid through the hollow interior of each said valve.

5. In a reversing valve mechanism, apparatus comprising, in combination, a pair of horizontally extending valve seats in spaced rigidly connected relation, a pair of ports in side-by-side relation extending through said valve seats, a valve adapted to be slid horizontally along each of said valve seats while in engagement therewith respectively, a track rigidly connected to each of said valve seats and extending generally along and above the path of movement of a valve on its said seat, said track having a longitudinal opening between the upper and lower sides thereof, a carriage movable on said track, said valve being connected to said carriage through said opening to support said valve for movement back and forth in engagement with its respective valve seat face, a cable adjacent said track and in alignment therewith to move said carriage back and forth, a heat-resistant flexible band connected to the outside of said cable and the underside of said carriage to substantially close said opening irrespective of the position of said carriage along said track.

6. In a reversing valve mechanism, apparatus comprising, in combination, a longitudinally extending valve seat, a port in said valve seat, a valve adapted to he slid horizontally along said valve seat to open and close said port, a track extending generally above the path of movement of said valve and having a longitudinal opening between the upper and lower sides thereof, a carriage movable on said track, a member connected to said carriage and extending downwardly through said opening, said valve being supportably connected to said member in depending relation below said opening for movement back and forth in engagement with said valve seat, means for moving said carriage on said track, and means for 7 covering said opening during such movement of said carriage.

7. In a reversing valve mechanism, apparatus comprising, in combination, a reciprocable carriage, a horizontal track on which said carriage is movable back and forth, a chain connected to the respective ends of said carriage to move it on said track, a hanger strap connected to said carriage and extending downwardly, a valve connected to said hanger to be moved horizontally by corresponding movement of said carriage, reversible means for moving said chain and thereby said carriage in opposite directions, longitudinally spaced means extending close to the sides of the path of movement of said hanger strap to structurally separate the area containing said valve from the area containing said carriage, and means for covering the space between said longitudinally spaced means.

8. In a valve mechanism, apparatus comprising, in combination, a reciprocal carriage, a track on which said carriage is moved, longitudinally extending spaced means defining a narrow space, a hanger connected to said carriage and extending downwardly through said narrow space, cable means connected to the respective ends of such carriage, said cable means overlying substantially the entire length of said narrow space not overlain by said carriage, and means afiixing a flexible band to the underside of said cable means and carriage to bear against said spaced means and maintain said narrow space substantially closed.

9. In a reversing valve mechanism, apparatus comprising, in combination, a reciprocable carriage, a horizontal track on which said carriage is movable back and forth, an endless chain connected to the respective ends of said carriage to move it on said track, a hanger connected to said carriage and extending downwardly, a valve connected to said hanger to be moved horizontally by cor responding movement of said carriage, reversible means for moving said chain and thereby said carriage in opposite directions in desired timing and sequence, spaced means extending close to the sides of the path of movement of said hanger to structurally separate the area containing said valve from the area containing said carriage, means for covering the space between said spaced means and for holding it in place by said chain means regardless of movements of said carriage, and cooling means connected to said valve and extending upwardly into said carriage area, said cooling means being in longitudinal alignment with said hanger.

10. In a reversing valve mechanism for furnace ducts, apparatus comprising, in combination, a horizontally extending valve seat having a pair of ports extending therethrough in side-by-side relation and adapted to be alternatively used, a plurality of furnace ducts in respective communication with said ports, a track extending generally along the top of said valve seat, spaced longitudinally extending portions inclusive of said track and defining a slot, a carriage movable to and fro on said track above the face of said valve seat, a support connected to said carriage and extending downwardly through said slot, a valve supportably connected to said support in such manner that said valve is in contact with said valve seat, means for moving said carriage back and forth along said track to close first one of said ports and then the other communicating respectively with different ones of said furnace ducts, and independent valve means having a pair of alternatively open ports respectively connected to said furnace ducts.

References Cited in the file of this patent UNITED STATES PATENTS 975,240 Hicks Nov. 8, 1910 1,503,465 Amsler Aug. 5, 1924 1,511,544 Wagner Oct. 14, 1924 1,560,287 Murphy Nov. 3, 1925 1,681,328 Erickson Apr. 21, 1928 1,825,815 Nye Oct. 6, 1931 1,849,242 Moll Mar. 15, 1932 2,653,022. Armstrong u Sept, 22, 1953

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