US971357A - Boiler-feed-water regulator. - Google Patents

Boiler-feed-water regulator. Download PDF

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US971357A
US971357A US55092610A US1910550926A US971357A US 971357 A US971357 A US 971357A US 55092610 A US55092610 A US 55092610A US 1910550926 A US1910550926 A US 1910550926A US 971357 A US971357 A US 971357A
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water
boiler
tube
tubes
steam
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Howard E Cade
David R Knapp
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    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F22STEAM GENERATION
    • F22DPREHEATING, OR ACCUMULATING PREHEATED, FEED-WATER FOR STEAM GENERATION; FEED-WATER SUPPLY FOR STEAM GENERATION; CONTROLLING WATER LEVEL FOR STEAM GENERATION; AUXILIARY DEVICES FOR PROMOTING WATER CIRCULATION WITHIN STEAM BOILERS
    • F22D5/00Controlling water feed or water level; Automatic water feeding or water-level regulators
    • F22D5/14Controlling water feed or water level; Automatic water feeding or water-level regulators responsive to thermal expansion and contraction, e.g. of solid elements

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  • Our invention relates to that class of devices, wherein feed water is fed a-uton'iatically to a steam boiler, during evaporation, in order that the water may be kept at a constant level therein, and our objects are: first, to provide a simple and ei'licient means that may be attached thereto or integral therewith of a water controlling means in a boiler feed line to automatically control the water supply to said boiler; second, to provide a feed water regulator that is positive in its action and of a simple and cheap structure; third, to provide a means whereby the small movement of an expansive and contractive means attached to or integral with a means in the feed line for controlling the supply of water therein and adapted to be actuated by the level of the water in the boiler may be effectively multiplied so as to effectively operate the said means in the feed line; fourth, to provide a construction, wherein the use of an expansive tube is employed that may be inserted directly in the feed line and supported thereby, the same as a pipe fitting, and said construction so arranged, as
  • Figure 1 is an elevation showing a convenient embodiment of our said invention
  • Fig. 2 is a plan showing in more detail the connection between the pivot block and the adjustable rod
  • Figs. 3 and 4t are, respec tively, elevation and plan views showing in more detail the method of attaching the valve stem to the adjustable rods
  • Fig. 5 is a section on C D of Fig. 1, showing Specification of Letters Patent.
  • the numeral designates a water column found on steam boilers to visually indicate the level of the water in the boiler and such level is indicated by the line i ⁇ -B.
  • 1 and 2 designate expansive and contractive means preferably tubes of equal length made from some metal having a high coetlicient of expansion and said tubes are located above the water level of the boiler.
  • 21 designates a pipe line of small diameter to enable it to have flexibility and is connected to one end of said tube 1 to be in steam communication therewith and to the water column at a point designated by the water level that is desired to be maintained.
  • the said pipe 21 designates a pipe of similar construction to that of pipe '21 and is in steam com munication with the end of tube 2 and also connects to some point below the desired water level of the boiler which is preferably at the lower portion of the water column.
  • the said pipe 21 communicates steam to the said tubes 1 and 2 when the water level in the water column falls below the point where the pipe 21 connects thereto and the pipe 23 drains back to the boiler any water due to the condensation of steam which takes place when said tube is deprived of steam due to the water rising in the water column and closing or sealing pipe 21 to any steam supply. It is obvious that the said tubes 1 and 2 will be subjected toa wide range of temperature which will cause them to expand and contract as the steam thereto is admitted and cut off.
  • annularport 26 with which the tubes 1 and 2 are in steam communication and which allows a free passage of steam from tube 1 to tube 2.
  • 2T designates a feed water supply line delivering water above boiler pressure tothe said boiler and inserted therein is a water controlling means 28, preferably a valve and to which is rigidly secured or integral therewith the member 15.
  • Said connecting rods are provided with turnbuckles 9 and 10 which are adapted to move longitudinally on said rods to adjust the lengths thereof and are locked to said rods by the jam nuts 11 and 12 located on either side of said turn buckles 9 and 10. It is obvious that any movement of the turnbuckles will effect a vertical adjustment of the cross head 37.
  • Said stein passes vertically through the center of the member 15 and is secured to the said crosshead 37 by threaded engagement and by the jam nuts 16 and 17 located on either side of said member 37.
  • the weight 18 which is secured thereto by threaded engagement and extending from said weight is the pin 20 over which is adapted to loosely pass any additional weights 19, for adjustment.
  • a yielding means preferably a flat spring interposed in the valve stem 25 and located in a position intermediate of the cross head 37 and the member 15.
  • valve stem By positioning the valve stem at right angles to the said tube and pivotally connecting the free end of the tube to the valve stem by a connecting rod so that said rod forms an acute angle with reference to said tube, it obvious that any slight movement in the length of the saidtube will raise or lower the vah'e stem due to the shifting of the fulcrum 31 so long as the connecting rod remains of a constant length.
  • a straight expansive tube rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, i'neans for controlling the water supply to the boiler operatively connected to the apex of said triangular formation, and means for conducting water or steam to said tube depending upon the water level in the boiler.
  • a straight expansive tube adjustable rods connecting the ends of said tube to form an isosceles triangle with said tube as a. base, means for controllingthe water supply to the boiler operatively connected to the apex of said triangular formation, and means for (".ondiucting water or steam to said tube depending upon the water level in the boiler.
  • a feed line In a boiler feed water regulator of the character described, a feed line, a straight expansive tube, rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, means in the feed line for controlling the water supply therein, the apex of said triangular formation operatively connected to said means. and means for conducting water or steam to said tube depending on the water level in the boiler.
  • a straight expansive tube rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, means for controlling the water supply to the boiler operatively connected to the apex of said triangular formation, resilient means interposed intermediate of said apex and said means, and means for conducting water or steam to said tube depending upon the water level in the boiler.
  • a straight expansive tube rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, means for controlling the water supply to the boiler operatively connected to the apex of said triangular formation, a counter balance weight operatively connected to said means, and means for conducting water or steam to said tube depending upon the water level in the boiler.
  • expansion tubes In a boiler feed water regulator, expansion tubes, one end of each fixed to a common member, rods connected to the free end of said tubes, a second member adapted to move at right angles to said tubes, the opposite end of said rods connected to the said second mentioned member, a valve in the feed ater line operatively connected to the said second mentioned member, and means for conduct- .ing water or steam to said tubes depending upon the Water level in the boiler.
  • a boiler feed water regulator of the 1 character described an expansive tube, a member operatively connected to said tube and adapted to move at right angles thereto at a point equidistant from the ends thereof, means for controlling the water supply to said boiler operatively connected to said member, a resilient member interposed intermediate of said means and said member, and means for conducting water or steam to said tube depending upon the 'ater level in the boiler.
  • eX- pansion tubes one end of each fixed to a common member, rods pivotally connected to the free end of said tubes, a second member adapted to move at right angles to said tubes, the other end of said rods pivotally connected to the said second mentioned mem her, an operative means in the feed water line controlling the water supply therein, operatively connected to the said second mentioned member, and means for conducting water or steam to said tubes depending upon the water level in the boiler.
  • a boiler feed water regulator of the character described, the combination with a feed line and an operative means for controlling the water supply therein, of expansion tubes rigidly secured at one end, adjustable rods connecting the free ends of said expansion tubes to the operative means, a resilient means interposed intermediate of said connection, a weight in operative relation with said operative means, and means for conducting water or steam to said tubes depending upon the water level in the boiler.
  • a boiler feed water regulator the combination with means for controlling the water supply to the boiler, a tube, amember adapted to move at right angles to said tube, operatively connected to said means, rods connecting the extremity of said tube to said member, resilient means interposed between said means and said member, and means for conducting water or steam to said tube depending upon the water level in the boiler.

Description

H. E. GADE & D. R. KNAPPQ BOILER FEED WATER REGULATOR.
APPLIOATION FILED MAR. 22, 1910.
Patented Sept. 27, 1910.
n15 norm): PETERS c0., vmsnmanm, o. c.
HOWARD E. CADE, OF PENCOYD, AND DAVID R. KNAPP, F PHILADELPHIA, PENNSYLVANIA.
BOILER-FEED-WATER REGULATOR.
T 0 all whom it may concern:
Be it known that we, Howann E. Gama and DAVlD R. KNAPP, citizens of the United States, and residents, respectively, of Pencoyd, in the county of Montgomery, and of Philadelphia, in the county of Philadelphia, both in the State of Pennsylvania, have invented certain new and useful Improvements in Boiler-Feed-W ater Regulators, of which the following is a specification.
Our invention relates to that class of devices, wherein feed water is fed a-uton'iatically to a steam boiler, during evaporation, in order that the water may be kept at a constant level therein, and our objects are: first, to provide a simple and ei'licient means that may be attached thereto or integral therewith of a water controlling means in a boiler feed line to automatically control the water supply to said boiler; second, to provide a feed water regulator that is positive in its action and of a simple and cheap structure; third, to provide a means whereby the small movement of an expansive and contractive means attached to or integral with a means in the feed line for controlling the supply of water therein and adapted to be actuated by the level of the water in the boiler may be effectively multiplied so as to effectively operate the said means in the feed line; fourth, to provide a construction, wherein the use of an expansive tube is employed that may be inserted directly in the feed line and supported thereby, the same as a pipe fitting, and said construction so arranged, as to multiply the small movement of the expansive tube so that it may effectively operate the water controlling means in the feed line.
. \Vith these objects in view our invention consists in certain novel features of construction and arrangement of parts as will hereinafter be more fully described and pointed out in the claims, reference being had to the accompanying drawing forming part of this specification and in which,
Figure 1 is an elevation showing a convenient embodiment of our said invention; Fig. 2 is a plan showing in more detail the connection between the pivot block and the adjustable rod; Figs. 3 and 4t are, respec tively, elevation and plan views showing in more detail the method of attaching the valve stem to the adjustable rods; and Fig. 5 is a section on C D of Fig. 1, showing Specification of Letters Patent.
Application filed March 22, 1810.
Patented Sept. 27, 1910.
Serial No. 550,926.
' an annular port through which the steam is communicated from tube to tube.
Referring to the figures, in which similar numerals of reference refer to similar parts throughout the several views, the numeral designates a water column found on steam boilers to visually indicate the level of the water in the boiler and such level is indicated by the line i\-B.
1 and 2 designate expansive and contractive means preferably tubes of equal length made from some metal having a high coetlicient of expansion and said tubes are located above the water level of the boiler.
21 designates a pipe line of small diameter to enable it to have flexibility and is connected to one end of said tube 1 to be in steam communication therewith and to the water column at a point designated by the water level that is desired to be maintained.
23 designates a pipe of similar construction to that of pipe '21 and is in steam com munication with the end of tube 2 and also connects to some point below the desired water level of the boiler which is preferably at the lower portion of the water column. The said pipe 21 communicates steam to the said tubes 1 and 2 when the water level in the water column falls below the point where the pipe 21 connects thereto and the pipe 23 drains back to the boiler any water due to the condensation of steam which takes place when said tube is deprived of steam due to the water rising in the water column and closing or sealing pipe 21 to any steam supply. It is obvious that the said tubes 1 and 2 will be subjected toa wide range of temperature which will cause them to expand and contract as the steam thereto is admitted and cut off.
15 designates amember to which is secured by threaded engagement the said tubes 1 and 2. Said tubes are positioned at a straight angle in reference to each other forming a straight tube. We do not wish to limit ourselves to a construction wherein two tubes are used as it is obvious that a continuous tube could be employed provided the valve 28 was in a position where the weight 18 now is and the tube was properly supported from the valve 28 at a point equidistant from the ends of the tube, and that part of the valve seem intermediate of the Said member 15 is provided with an inner cross-head 37 and the member 15 eliminated.
annularport 26 with which the tubes 1 and 2 are in steam communication and which allows a free passage of steam from tube 1 to tube 2.
2T designates a feed water supply line delivering water above boiler pressure tothe said boiler and inserted therein is a water controlling means 28, preferably a valve and to which is rigidly secured or integral therewith the member 15.
e do not wish to limit ourselves to any particular type of water controlling means as it is obvious that a balanced valve could be used in lieu of the stop valve as shown, or an injector could be used as said controlling means or any other of the many forms of controlling means; furthermore if a feed water pump is used with a single boiler, the said water controlling means could be a steam supply valve to the pump stopping and starting the pump for controlling the water supply to the boiler, however the valve 28 designates a convenient means to illustrate the operation of our improved device and that it will be understood said controlling means forms no element of our in vention.
3 designates a pivot block to which the free end of the tube 1 is secured by threaded engagen'ient, and 1 designates a similar pivot block secured by threaded engagement to the free end of the tube 2.
(5 and 7 designate adjusting rods, the ends of which terminate by threaded engagement respectively, into the terminal blocks 5 and S. Said pivot blocks 3 and 1 are provided with ears adapted to embrace the said terminal block and are secured thereto in pivot relation by the screw 31.
37 designates a cross head provided with the ears 29 which are adapted to embrace the terminal blocks 13 and 1 1 and which are secured thereto in pivotal relation by the screws 30. Said terminal blocks 13 and 1 1 are secured, respectively, by threaded engagement to the adjusting rods 6 and 7. Said rods are positioned in the same plane with the said tubes 1 and 2 but not parallel therewith and it is obvious therefore that any lengthening of the tubes 1 and 2 due to expansion will tend to position said rods parallel with the tubes and which will result in a downward movement of the cross-head 37 and an opposite movement upon the contraction of said tubes. Said connecting rods are provided with turnbuckles 9 and 10 which are adapted to move longitudinally on said rods to adjust the lengths thereof and are locked to said rods by the jam nuts 11 and 12 located on either side of said turn buckles 9 and 10. It is obvious that any movement of the turnbuckles will effect a vertical adjustment of the cross head 37.
25 designates a member adapted to move in a plane at right angles to said tubes and is operatively connected to the valve 28 forming a stem therefor. Said stein passes vertically through the center of the member 15 and is secured to the said crosshead 37 by threaded engagement and by the jam nuts 16 and 17 located on either side of said member 37. At the end of said stem is fixed the weight 18 which is secured thereto by threaded engagement and extending from said weight is the pin 20 over which is adapted to loosely pass any additional weights 19, for adjustment.
36 designates a yielding means, preferably a flat spring interposed in the valve stem 25 and located in a position intermediate of the cross head 37 and the member 15. After the valve has been seated, further movement of the crosshead due to the expansion and contraction of the tubes 1 and 2 will be taken up by said yielding means thereby taking the strain off of the operative members.
2 1 designates a stuffing box around the said valve stem and located on the upper part of the member 15 thereby preserving the watertightness of the member 15.
Having thus described the various parts throughout the several views, all of which will be readily understood by those skilled in the art to which this invention relates its mode of operation will be substantially as follows: 'hen the water in the boiler is at its normal level the water in the water column seals the steam supply to the pipe 21 and the parts are in a position as shown in the drawing with the valve 28 closed. \Vhen the water in the boiler falls below the normal level A-B, the water seal to the pipe 21 is broken and steam from the upper half of the water column is admitted to said pipe 21 which communicates it to the tube 1, thence through the annular port 26 to the tube 2. Said tubes 1 and 2 being now subjected to the high temperature of the steam increases in length and the following movements take place: The relative position of the elements as shown is such that the connecting link 13 is higher than the pivot 31 which obviously forms a triangle with the tubes 1 and 2 as a base, the rods 6 and 7 as the two sides and the valve stem 25 as the altitude. It is obvious that in such a case if the base length ens and the two sides remain of a constant length the altitude must decrease. Therefore when the said tube increases in length due to the communication of steam supply thereto caused by the fall of water in the boiler the connecting link 13 is forced down which forces the valve stem down and opens the valve to the feed line. ater is now admitted to the boiler in such a quantity as to bring the levelup to the normal when the water in the water column will act as a seal to the steam to the pipe 21. The absence of steam from the tubes 1 and 2 will cause the tubes to cool and contract which will reverse the movements aforesaid and close the valve to the water supply. The feed water pressure acting below the valve is always greater than the boiler pressure which acts on the top of said valve. The weight 18 coacting with the steam pressure compensates for the difference and allows the valve to become practically balanced which relieves the tube of any great amount of work to do when expanding and contracting.
The foregoing movements and the structure as described shows an operative structure that is effective in its operation and the absence of any complicated parts makes it simple in operation and cheap in construc tion, thus accomplishing the heretofore first and second mentioned objects of our said invention.
The difference in the length of the tube due to expansion and contraction is exceedingly small and the effective movement of the valve stem is required to be comparatively large. By positioning the valve stem at right angles to the said tube and pivotally connecting the free end of the tube to the valve stem by a connecting rod so that said rod forms an acute angle with reference to said tube, it obvious that any slight movement in the length of the saidtube will raise or lower the vah'e stem due to the shifting of the fulcrum 31 so long as the connecting rod remains of a constant length. By designing the structure so that the strain becomes equal on opposite sides of the valve stem the effect of binding is eliminated from the valve stem, thus accomplishing the heretofore third mentioned object of our said invention Our device being installed directly in the feed line the same as an ordinary pipe fitting does not require any attachment means to the boiler or its supports which are very often undesirable due to low ceilings and sometimes to the type of boiler construction itself inasmuch as some types of boilers do not olfer any desirable means of securing such devices. Our device being directly supported by the feed line and inserted therein offers a very ready and desirable means for installation. This together with a construction as described wherein a small movement of the expansion tubes is effectively multiplied to operate a valve in the feed line accomplishes the heretofore fourth mentioned objectof our said invention.
lVe do not wish to limit ourselves to the exact construction as shown in the drawing as it is obvious that slight departures may be had therefrom without departing from the spirit and intent of our said invention.
lVe are aware that expansion tubes have been employed in feed water regulators but know of none where the movement of the expansion tube is effectively multiplied to operate a valve in the feed water line, and
W hat we therefore claim as new and desire to secure by Letters Patent, is:
1. In a boiler feed water regulator of the character described, a straight expansive tube, rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, i'neans for controlling the water supply to the boiler operatively connected to the apex of said triangular formation, and means for conducting water or steam to said tube depending upon the water level in the boiler.
52. In a boiler feed water regulator of the character described, a straight expansive tube, adjustable rods connecting the ends of said tube to form an isosceles triangle with said tube as a. base, means for controllingthe water supply to the boiler operatively connected to the apex of said triangular formation, and means for (".ondiucting water or steam to said tube depending upon the water level in the boiler.
3. In a boiler feed water regulator of the character described, a feed line, a straight expansive tube, rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, means in the feed line for controlling the water supply therein, the apex of said triangular formation operatively connected to said means. and means for conducting water or steam to said tube depending on the water level in the boiler.
4. In a boiler feed water regulator of the character described, a straight expansive tube, rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, means for controlling the water supply to the boiler operatively connected to the apex of said triangular formation, resilient means interposed intermediate of said apex and said means, and means for conducting water or steam to said tube depending upon the water level in the boiler.
5. In a boiler feed water regulator of the character described, a straight expansive tube, rods connecting the ends of said tube to form an isosceles triangle with said tube as a base, means for controlling the water supply to the boiler operatively connected to the apex of said triangular formation, a counter balance weight operatively connected to said means, and means for conducting water or steam to said tube depending upon the water level in the boiler.
In a boiler feed water regulator, expansion tubes, one end of each fixed to a common member, rods connected to the free end of said tubes, a second member adapted to move at right angles to said tubes, the opposite end of said rods connected to the said second mentioned member, a valve in the feed ater line operatively connected to the said second mentioned member, and means for conduct- .ing water or steam to said tubes depending upon the Water level in the boiler.
7. In a boiler feed water regulator of the 1 character described, an expansive tube, a member operatively connected to said tube and adapted to move at right angles thereto at a point equidistant from the ends thereof, means for controlling the water supply to said boiler operatively connected to said member, a resilient member interposed intermediate of said means and said member, and means for conducting water or steam to said tube depending upon the 'ater level in the boiler.
8. In a boiler feed water regulator of the character described, the combination with a feed line and an operative means for controlling the water the-rein, of expansion tubes rigidly secured at one end, rods connecting the free ends of said tubes to said operative means, a resilient means interposed intermediate of said connection, and means for conducting water or steam to said tubes depending upon the water level in the boiler.
9. In a boiler feed water regulator, eX- pansion tubes, one end of each fixed to a common member, rods pivotally connected to the free end of said tubes, a second member adapted to move at right angles to said tubes, the other end of said rods pivotally connected to the said second mentioned mem her, an operative means in the feed water line controlling the water supply therein, operatively connected to the said second mentioned member, and means for conducting water or steam to said tubes depending upon the water level in the boiler.
10. In a boiler feed water regulator of the character described, the combination with a feed line and an operative means for controlling the water supply therein, of expansion tubes rigidly secured at one end, adjustable rods connecting the free ends of said expansion tubes to the operative means, a resilient means interposed intermediate of said connection, a weight in operative relation with said operative means, and means for conducting water or steam to said tubes depending upon the water level in the boiler.
11. In a boiler feed water regulator, the combination with means for controlling the water supply to the boiler, a tube, amember adapted to move at right angles to said tube, operatively connected to said means, rods connecting the extremity of said tube to said member, resilient means interposed between said means and said member, and means for conducting water or steam to said tube depending upon the water level in the boiler.
In testimony whereof we have signed our respective names to this specification in the presence of two subscribing witnesses.
HOWARD E. CADE. DAVID R. KNAPP.
\Vitnesses E. S. FROST, FLEMING G. JOHNSON, Jr.
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