US2145558A

US2145558A - Fluid control mechanism

Info

Publication number: US2145558A
Authority: US
Inventors: William V Sauter; Howard F Lawrence
Original assignee: American Engineering Co Ltd
Current assignee: American Engineering Co Ltd
Priority date: 1936-01-14
Filing date: 1937-01-08
Publication date: 1939-01-31
Anticipated expiration: 1956-01-31

Description

Jan. 31, 1939. W v A TER AL 2,145,553

FLUID CONTROL MECHANISM Original Filed Jan. 14, 1936 2 Sheets-Sheet, l

W V. SAUTER ET AL Jan. 31, v1939.

FLUID CONTROL MEGHANI SM Original Filed Jan. 14, 1936 2 Sheets-Sheet 2 Patented Jan. 31, 1939 UNETED STATES PATENT OFFICE FLUID CONTROL MECHANISM of Pennsylvania Original application January 14, 1936, Serial No. 59,042. Divided and this application January 8, 1937, Serial No. 119,607

8 Claims.

This application is a division of our pending application Serial No. 59,042, filed January 14, 1936, and the invention herein described relates to fluid systems, and more particularly to systems employed to control the flow of draft air to stoker furnaces.

One object of the present invention is to provide a generally improved arrangement of dampers which control the flow of draft air to the individual tuyeres or groups of tuyeres of a stoker furnace.

Another object is to provide a damper mechanism for stoker furnaces which controls the flow of draft air to the individual tuyeres or groups of adjacent tuyeres, said dampers being so disposed that the pressure of the air flowing past one or more of the dampers will control, to a certain extent, the operation of adjacent dampers.

Other and further objects will become apparent as the description of the invention progresses.

Of the drawings:

Fig. l is a longitudinal view partly in section, taken through one of the tuyere chambers of a stoker furnace showing control dampers associated with each of the tuyeres thereof.

Fig. 2 is an enlarged View partly in section, taken through the upper end of one of the tuyere chambers of a stoker showing the preferred type of dampers associated with the tuyeres thereof.

Fig. 3 is a view similar to Fig. 2, but showing an alternative form of damper mechanism.

Fig. 4 is a similar view showing a still further arrangement of dampers.

Fig. 5 is an enlarged view, partlyin section, showing dampers of the type shown in Fig. 2 provided for groups of tuyeres.

t is believed to be a fundamental principle of hydraulics that the total head of a fluid flowing through a duct or passage is equal to the sum of the static and velocity heads. The rate of flow through such a duct is determined by the velocity pressure or velocity head. Therefore, it is apparent that as the flow increases a certain amount of the static pressure is converted into velocity pressure, and when no flow exists in the ducts the total pressure is substantially static pressure.

The present invention, for the purpose of illustration, is shown applied to a stoker of the underfeed type, although it is apparent that the invention is equally applicable to other types of stokers, as well as other apparatus, wherein control of a, fluid is desired. As illustrated in the drawings, each tuyere or group of tuyeres of the stoker is provided with a damper. These dampers are so disposed as to form with each other communicating passages to the tuyeres. In cases where the area of these communicating passages is substantially the same as the area of the tuyere openings, the pressure of the air therein is substantially the same as that flowing through the tuyeres. In the present instance the dampers are so arranged that one surface of each is subjected to the pressure of the air flowing through one such passage, while another surface is subjected, in part or wholly, to the pressure of the air flowing through an adjacent tuyere. In cases where one surface of each of the dampers is subjected only in part to the pressure in a passage the remaining portion thereof is subjected to the pressure of the air at the source of supply, which, in effect, is substantially the total pressure of the air flowing through any of the ducts. It therefore is seen. that when any flow exists through the tuyeres each damper is subjected to diiferential pressure. Thus, should thin or extremely porous spots develop in the fuel bed, the damper or dampers controlling the air thereto will close. When this occurs greater inlet openings will be provided in the passages leading to the tuyeres supporting the adjacent thicker or less porous portions of the fuel and as a result the latter will receive a greater quantity of air. The dampers therefore tend to maintain the fuel bed normally uniform throughout and prevent blowing of the fuel in the event abnormally thin spots occur therein.

The drawings illustrate a number of different types of damper arrangements, and each will now be described in detail. 3

Referring to the drawings, numeral l indicates a stoker of the inclined grate underfeed type having alternately disposed tuyere rows 2 and retorts 3. Each tuyre row 2 comprises a series of tuyere blocks 4 arranged in superimposed relation and may be of the general type shown and described in United States Patent No. 1,930,908. Fuel is supplied to the stoker from a hopper 5 by any suitable feeding mechanism driven by the power mechanism shown at 6. A series of pushers I, provided in the bottom of each retort, are also driven by the power mechanism 6 through a link and lever mechanism indicated generally by the numeral 9. Draft air is supplied to the fuel bed through the tuyre blocks 4 from a common plenum chamber It disposed beneath the stoker. Air is supplied to plenum chamber l0 in accordance with the fuel burning rates, by any suitable fan or blower mechanism (not shown) through a duct Ill. The usual extension grates H pro- 55 vided at the lower end of the stoker feed the consumed fuel into an ash pocket or to dump grates (not shown) after a well known fashion.

The terms front and rear hereinafter employed in the description of the various elements, it is to be understood, relate to those portions thereof extending toward the front or driving mechanism 3, and to those portions extending toward. the rear or extension grates respectively, of the stoker.

Each tuyere block 4 comprises a rounded nose or rear portion I2, and a substantially rectangular front portion l2. A projection 3. depends from each side edge of each tuyre block 4 which space the main body portions thereof so as to form passages l4 therebetween. As shown in Fig. 2, each tuyre block has provided thereon a forwardly extending tailpiece |5 which extends between the side walls IB of the associated tuyre chamber H, the forward end of each of which being beveled, asshown at l8.

As shown more particularly in Fig. 2, the fluid control system comprises a series of units 9, each consisting of a frame 26 in which are mounted a series of dampers 2|.. Each frame 20 comprises a pair of side members 22 which may be secured to the side plates l6 of the associated tuyere chamber in any suitable manner, such as by bolts 23. A series of transverse members 24 arranged in spaced relation connect the side members 22 of the frame 20. A substantially vertical partition 25 depends from the forward end of each transverse-member 24 whereby the space between the side members 22 of the frame 20 is divided into aseries of compartments 26. Each damper 2| is pivotally mounted on a pin 29 extending between side members 22, and con sists of a pair of sidemembers 21-and 28 which are curved at theupper ends thereof so as to form passages between adjacent dampers of substantially Venturi form. The upper ends of members 27 and 28 are spaced apart so as to receive the lower ends of partitions 25 which act as stops to prevent movement of. the dampers out of operative position. The partition 25 disposed at the forward end of each unit I9 is provided with an arcuate protuberance 25 near the upper and lower ends thereof which cooperate with the end dampers 2| of adjoining units to form inlet passages of substantially Venturi form.

To assemble a unit H! in position it is placed between the side plates l6 and moved vertically until the transverse members 24- engage the forwardly disposed beveled portions I 8 of the tuyre blocks, as shown in Fig. 2. In this construction it is seen that the dampers 2| are arranged in side by side relation, and consequently the flow of air between any pair of such dampers is controlled by the pressure of the air in adjacent passages. When the pressure of the; air flowing through the passages is the same an equal force will be exerted on each side of the dampers, and as a result they will be held in upright position. However, should the rate of flow of the fluid through any of the passages increase, thereby creating a reduced staticpressure therein, while the rate of flow in adjacent passages remains substantially the same as before, then due to the greater static pressure operating on one side of each of such dampers, than that operating on the other side thereof, said dampers will be actuated towards each other to throttle the flow of air in the passage or passages of low pressure, while permitting a greater quantity of air to flow through the passages of higher pressure.

form condition is interrupted the dampers will respond accordingly to permit greater or lesser quantities of air to pass to the fuel bed, as the case may be. The dampers therefore will automatically adjust themselves so as to assume a position which permits the proper quantity of air to flow through each subdivision of the fuel bed under all conditions of operation.

Fig. 3 shows a somewhat different type of damper construction. This construction also comprises a series of units 30, each unit consisting of a framework 32 having a series of substantially vertically disposed dampers 3| mounted therein. Framework 32 also consists of a pair of side plates 33 connected at the upper ends thereof by a series of cross members 34 arranged in spaced relation and adapted to engage the forward ends of the tuyre blocks 35. Depending from the forward end of each cross member 34 is a substantially vertical partition 36. Each damper 3| is pivotally mounted at the lower end thereof at 31, and consists of substantially flat side plates 38 and 39 which terminate at the upper ends thereof in a substantially arcuate portion 40. In this construction also the dampers 3| are also arranged in side by side relation and consequently the flow of air between any pair of such dampers is controlled by the pressure of the air on either side thereof. Thus the dampers 3| also move towards each other when the flow of air through the associated tuyeres increases to thereby throttle the flow of air thereto, and move away from each other when the flow of air decreases to permit a greater quantity of air to flow through the associated tuyres. To prevent the dampers 3| from moving out of operative position stops 3| are provided. These stops extend inwardly from the side plates 33 of the framework and are disposed midway between the side plates 38 and 39 of the dampers when the latter are in upright position. The partition 36 at the forward end of each unit 30 is also provided with a protuberance 36 near the upper and lower ends thereof which cooperate with the end dampers 3| of adjoining units to form restricted throats for the passages leading to the associated tuyres.

Fig. 4 shows a still further modification of the present invention. In this construction each unit 4| also comprises a frame 42 having cross members 43 against which the forward ends of the tuyere blocks 44 abut. The dampers 45 of each unit are arranged in stepped relation, each damper being pivotally mounted on a pin 46 extending between the side plates 41 of the unit. A partition 48 extends downwardly from each cross member 43. These partitions are also arranged in stepped relation and the lower ends thereof lie in substantially abutting relation with the upper arcuate portions 49 of the associated dampers. These dampers also comprise a pair of substantially flat side members 56 and 5|. In this construction it will be seen that the dampers 45 overlap each other and therefore each is controlled to a certain degree by the pressure of the air flowing in the passages disposed at the sides thereof. The lower extremity of the side wall 59 of each damper is also subjected to the pressure of the air in plenum chamber 52. Therefore, while each damper is controlled to a certain extent by the pressure of the air flowing in the passages at either side thereof, this differential pressure is offset, to a certain degree, by the plenum chamber pressure also acting thereon. In this construction, like that shown in Fig. 3, each damper 55 is held in operative position by a stop element 45.

Fig. 5 shows the invention applied to groups of tuyeres. In this construction the tuyere blocks 5 1 are divided into groups of four, although it is apparent that they may be divided into groups of other numbers without departing from the invention. In this construction, also, the control units 55 may each comprise a framework 56 consisting of spaced side plates 51 connected at the upper ends thereof by cross members 58, which in assembly engage the forward ends of the tuyere blocks 54. A partition 59 in the present instance depends from every fourth cross mem- 53 dividing the tuyere blocks into groups of four, and extends between the side plates 51 of the framework 56, defining passages 60 for draft air. A damper iii is disposed beneath each partition 59 and extends between the side plates of the framework 56. Each damper is pivoted at the lower end thereof at 62, and is generally similar in structure and operation tothe dampers 21 shown in Fig. 2. In this construction, like that shown in Fig. 2, the partition 59 provided at the forward end of each unit 55 is also provided with an arcuate protuberance 59* near the upper and lower ends thereof for the purpose previously described.

From the foregoing description it is apparent that the dampers 6! will move toward or away from each other to permit lesser or greater amounts of air to pass to the fuel bed, as the case may be, depending upon the conditions of the fuel bed supported by the groups of tuyere blocks 54. Other specific types of dampers, obviously, may also be employed in the construction shown in Fig. 5 without departing from the invention.

While the embodiments herein described are admirably adapted to fulfill the objects primarily stated, it is to be understood that the invention is not to be limited thereto, since it may be embodied in other forms, all coming within the scope of the claims which follow.

What is claimed is:

1. A fluid control device adapted to control v the flow of fluid from a source of supply to a series of passages, said device comprising, means defining said passages, dampers disposed in substantial alignment with said means and movable by diflerential pressure for controlling the flow of fluid to said passages, pairs of said dampers forming communicating passages to said passages first named, and said pairs of dampers being so disposed that the adjacent sides of each of said pairs is subjected to the pressure of the fluid in an associated communicating passage, and the opposite sides of said pairs of dampers being subjected to the pressure in adjacent communicating passages whereby said pairs of dampers will move toward or away from each other, depending upon the pressures operating on the opposite sides thereof resulting from changes in the velocity of fluid in said communicating passages,

2. A fluid control device adapted to control the flow of fluid from a source of supply to a series of passages, said device comprising partition means defining said passages, a damper disposed at one end of each of said partitions and operable in either direction by differential pressure, one side of each of said dampers being exposed to the pressure of the fluid flowing to an associated passage, while the other side thereof is subjected, at least in part, to the pressure of the fluid flowing to an adjacent passage, whereby said dampers will throttle the flow of fluid to the passages having the lower pressure resulting from an increase in the velocity of the fluid flowing thereto.

3. A fluid control device adapted to control the flow of fluid from a source of supply to a series of passages, said device comprising substantially vertical partitions defining said passages, a substantially vertical damper operable by differential pressure disposed beneath each of said partitions, one side of each of said dampers being exposed to the pressure of the fluid flowing to an associated passage, while the other side thereof is exposed at least in part, to the pressure of the fluid flowing to an adjacent passage, whereby said dampers will throttle the flow of fluid tothe passages having the lower pressure resulting from an increase in the velocity of the fluid flowing thereto.

l. A fluid control device adapted to control the flow of fluid from a source of supply to a series of passages, said device comprising, one or more control units, each of said control units comprising a framework consisting of a pair of side walls arranged in spaced relation, and a series of spaced cross members, a substantially vertical partition depending from each of said cross members, said partitions defining said passages, a plurality of dampers operable by diflerential pressure pivotally supported in said framework, one damper being disposed beneath and in substantially abutting relation with each of said partitions, said dampers being so arranged that one of the sides of each pair of adjacent dampers is subjected to the pressure of the fluid flowing to an associated passage, while the other sides of said pairs of dampers are subjected to pressure of the fluid flowing to adjacent passages whereby said pairs of dampers will move toward each other to throttle the flow of fluid to the associated passages when the static pressure of the fluid flowing through the latter is less than that of the fluid flowing through the adjacent passages as a result of changes in the velocity of the fluid.

5. A fluid control device adapted to control the flow of fluid from a source of supply to a series of passages, said device comprising, one or more control units, each of said control units comprising a framework consisting of a pair of side walls arranged in spaced relation, and a series of spaced cross members connecting said. side walls, a substantially vertical partition depending from each of said cross members, said partitions defining said passages, a plurality of dampers operable by difierential pressure pivotally supported in said framework, said dampers having curved side walls and being open at the upper ends thereof to receive the lower ends of said partitions, whereby adjacent dampers form inlet passages of substantially Venturi form, and said dampers being so disposed that the adjacent sides of each pair of said dampers are subjected to the pressure of the fluid flowing in an associated inlet passage, while the opposite sides of said pairs of dampers are subjected to the pressure of the fluid flowing in adjacent inlet passages, whereby the pressure of the fluid flowing in one of said passages. controls the operation of the dampers associated with adjacent passages.

6. A fluid control device adapted to control the flow of fluid from a source of supply to a series of passages, said device comprising, one or more control units, each of said control units comprising a framework consisting of a pair of side walls arranged in spaced relation, and a series of spaced cross members connecting said side walls, a substantially vertical partition depending from each of said cross members, said partitions defining said passages and being arranged in stepped relation, a damper operable by differential pressure disposed beneath and in substantially abutting relation with each of said partitions, said dampers being pivotally mounted in said framework, and also arranged in stepped relation, and said dampers being so disposed that one side of each is subjected to the pressure of the fluid flowing to an associated passage, whilethe other side thereof is partially subjected to the pressure of the fluid flowing to an adjacent. passage and partially to the pressure at said source of supply whereby said dampers will throttle the flow of fluid to said passages in which the rate of flow is greatest.

7. A fluid control device adapted to control the flow of fluid from a source of supply to a series of passages, said control device comprising one or more control units, each of said control units comprising a framework having a series of substantially vertically disposed dampers operable by differential pressurepivotally mounted therein, partition means provided in said framework defining said passages, one of said dampers being operatively associated with each of said partitions, said dampers being so disposed that one of the sides-of each pair of adjacent dampers is subjected to the pressure of the fluid passing to an associated passage, while the other sides of said pairs of dampers are subjected to the pressure of the fluid flowing to adjacent passages, whereby said pairs of dampers will move toward each other to throttle the flow of fluid in the associated passage when the static pressure of the fluid flowing in the latter is less than that flowing through adjacent passages as a result of an increase in the velocity of the fluid flowing thereto.

8. A fluid control device for controlling the delivery of fluid from a source of supply comprising partition means cooperating to form a series of passages communicating with the source of supply, damper means pivotally mounted adjacent the end of each partition means and each having a pair of faces constituting a flow controlling member of substantially V-form, one face of each of said damper means extending into the path of flow to the passages formed on opposite sides of said partitions, the dampers being freely movable by the flow of fluid therepast, and the arrangement being such that when the velocity of flow between any two dampers and to the passage controlled thereby increases the said two dampers are moved toward each other to throttle the flow therebetween and efiect increased flow in the adjacent passages.

WILLIAM V. SAUTER. HOWARD F. LAWRENCE.