US2119771A

US2119771A - Apparatus for securing uniform drying of the sheet in paper making machines

Info

Publication number: US2119771A
Application number: US40754A
Authority: US
Inventors: Arthur E Broughton
Original assignee: Individual
Current assignee: Individual
Priority date: 1935-09-16
Filing date: 1935-09-16
Publication date: 1938-06-07
Anticipated expiration: 1955-06-07

Description

June 7, 1938.

A. E. BROUGHTON APPARATUS FOR SECURING UNIFORM DRYING OF THE SHEET IN PAPER MAKING MACHINES Filed Sept. 16, 1935 I L kn 2 Sheets-Shoot 1 m fi jnventor ofneys:

June 7, 1938. r BROUGHTQN 2,119,771

APFARATUS FOR SECURING UNIFORM DRYING OF THE SHEET IN- PAPER MAKING MACHINES Fil ed Sept. 16. 1935 2 Sheets-Sheet 2 making machine UNITED STATES, PATENT OFFICE This invention relates to More specifically, it relates esses and machines.

APPARATUS mo MACHINES FOR SECURING UNIFORM DRYING OF THE SHEET IN PAPER MAK- Arthur-E. Broughton, Neenah, Wis. I Application September 16,1335, Serial No. 40,754

I 5 Claims. (Cl. 3H8) paper making procto methods and apparatus for uniformly controlling the moisture conte is dried in a paper It is an object of the nt of the paper sheet as it making machine.

present invention to provide novel and improved methods and apparatus for controlling the sheet as it passes over moisture content of the paper the drying cylinders of a paper making machine, so as to secure even and uniform drying of the sheet irrespective of variance in the sheet formation and to also secure at the dry end of the desired uniform More specifically,

the machine a sheet having moisture content.

it is an object of the invention to maintain substantially uniform moisture content in the sheet a t the dry end of a paper by maintaining substantially constant steam pressure in certain of the drying cylinders of the supply of steam machine through regulating the to the certain drying cylinders by slight variance in the steam pressure in said certain cylinders above and below the said constant and increasing or decreasing the supply of steam to the other cylinders as the supply of steam to the certain cylinders is increased or de- 1 creased.

It is a further object pressure on the vario 0 paper making machine to maintain proper steam us drying cylinders of a for even and uniform dryingof the sheet by steam supply control mechanism automatically operated by the pressure of steamin one or more Of the drying cylinders 10- cated'most-closely adjacent the'wet end of the machine.

The objects and advantages of the invention will more fully appear from the following descripti on, made in connection panying drawings, wherein like reference characters refer to the same out the various views,

Fig. 1 is a diagramm illustrating portions ofincorporating therein invention, and

or similar parts throughand, in which,

atic view in side elevation a paper making machine apparatus embodying the Fig. 2 is a view partly in side elevation and partly in vertical section illustrating in an enfloor there are shown a inders' or driers of a p group of these driers 1 cent the wet end of the machine (four driers in.

the illustrated embodi numeral 3. Above this number of the drying cylaper making machine. A ocated most closely adjament) are designated by point where the first or left with the accom-- control valve 23 which has a branch conduit 8 connected thereto forward of the auxiliary conduits 1. The branch conduit 8 is provided with a horizontal portion and it is connected to a header 9 from which steam is supplied to thevarious driers 4 through auxiliary conduits l0.

Betweenthe point where branch conduit 8 connects with the steam supply conduit 6 and the hand auxiliary conduit l connects with the steam conduit 6, a control valve I I is provided in the conduit 6 for hand regulation of the steam supplied through the conduits to the driers 5. The stem Ila of valve H may be pivotally connected to a lever l2 pivoted at one end on a fulcrum l3 secured to the valve. and having connected at its other end an upwardly extending cable l4. Cable l4 passes through a tube IS in floor, 3 and is attached at its upper end to a screw l6 supported in a bracket I! and adjustable in length to and from lever l2 by means of thumb screw l8. Of course, other means may be employed for adjustably setting the valve ll.

Return lines l9 for carryingoif the air andthe water condensed from the steam in the various driers 4 and 5 are provided and these return lines run downwardly to check valves 28 connected to a water return pipe 2|. v

A by-pass 22 about the valve II is provided in the steam supply conduit 6. This by-pass 22 may be in the form of an inverted. U-tube as shown,

having one. leg connected to the steam supply conduit 6 between valve. H and branch conduit 8 and another leg connected to the steam conduit 8 between valve II and the first or left hand auxiliary conduit 1.. ,In the horizontal portion of the U-tube forming by-pass 22 is located a closes on down movement of its valve stem 23a and opens on up movement of its valve stem. Pivotally connected to valve stem 23a is one end of a lever 24 ,pivotally mounted on a fulcrum 25 attached to valve 23 and carrying a weight 26 adjacent its end opposite the end pivoted to valve stein 23a. The lever 24 near its weighted end is provided with a sliding rider 24a to which an upwardly extending chain or cable 21 is connected. Aset screw 24b curing the rider 23a to the lever 23 in a desired adjusted position.

Mounted in the horizontal portion of branch conduit 3 is a control valve 23 which closes on upward movement of its valve stem 23a and opens on downward movement of the said stem. The valve stem 23a is pivotally connected to a lever 29 pivoted on a-fulcrum 33 mounted on valve 28. Mounted on the right end portion of lever 29, as viewed in the drawings, is a weight 3|, while the upper end of cable 21 is connected to the left end of the lever. Lever 29 carries near its left end a sheave 32.

Mounted on the floor 3 is a type of manometer, which may be designated as an entirety by the letter A. This manometer may take various forms but in the illustrated form, manometer A is located below the sheave 32 and, it includes outer and

inner stand pipes

33 and 33. respectively. The outer stand pipe 33 is closed at its lower end and a closure ring 35 is provided between the inner and outer stand pipes at their upper ends.- The inner stand pipe 33 is supported from the ring 35 so that the lower end of the inner pipe, is disposed slightly above the bottom of the outerstand pipe 33. Both the upper and lower ends of the inner pipe are open. About midway-of the height of the stand pipes a partition 33 in the form of a flanged ring is provided between the two pipes and mounted in this partition are a number of small vertically extending tubes 31 projecting above the partition and open at both ends. A drain pipe 33 is connected to the outer stand pipe 33 to communicatetherewith immediately above the partition 33 and this drain pipe runs downwardly to form a U-shaped water trap portion 390. and then connects with one of the auxiliary conduits l3 through a check valve 33b. Below the partition 39 another drain pipe 39 connects at one end to the outer stand pipe 33 so as to communi cate at one end therewith and the other end of the drain pipe 39 is connected to drain pipe 39.

A float 30 flts within the inner stand pipe 33 and this float has connected to its upper end one end of a chain or cable 3| which .runs upwardly over sheave 32 and then downwardly along side of the outer stand pipe 33. The end of the chain or cable 3| not connected to float 39 has a pin 32 secured thereto and this pin is adapted to be received within any one of a number of vertically spaced pin receiving openings 33 formed in a vertical adjustment board 33 Secured as by legs 39 to the floor 3. Normally water or other liquid stands within the inner stand pipe 33 so as to at least partially buoy up the float 33 to relieve the lever 29 partially of the weight of this float. Lever 29 is so weighted by the weight 3! relative to the float 33 that as the height of liquid within the inner stand pipe 33 raises from a given position somewhat to further buoy up the float 33, the left end of the lever 29 is relieved of at least part of the weight of the float and the weight 3| will then depress the right end of the lever 29 somewhat to raise the left end of the lever and thereby raise valve stem 23a and clom valve 23 to a greater extent than formerly. At the same time that this action occurs, the chain or cable 21 will be raised somewhat to thereby raise the right end of lever 23 against the force of weight 23 and depress the left end of lever 23, thereby depressing valve stem 23a and moving the valve 23 to a more nearly closed position. As the column of liquid within the inner stand pipe 33 lowers somewhat from a is subject to only atmospheric pressure.

.the outer stand pipe 33. The

' receiving openings 33.

certain height, the float 33 exerts more weight upon the left end of lever 29 by reason of the fact that the liquid within the stand pipe 33 does not buoy up the float to the same extent. The increased force exerted by the float 33 on the left end of lever 29 willbe suflicient to overbalance the weight 3! slightly and depress the left end of lever 29 somewhat, thereby depressing valve stem 23a and opening valve 23 to a greater extent. As the left end of lever 29 is depressed somewhat, the right end of lever 23 may swing downwardly somewhat under the influence of the weight 26 and, as a result, the left end of lever 23 will rise to slightly raise the valve stem 23a and thereby open the valve 23 to a greater extent than formerly.

A water glass 36 for showing the level of liquid within the outer stand pipe 33, is preferably connected at spaced points'to this pipe below partition 39.

A steam pipe 31 affords communication between header 9 and the upper part of the stand pipe 33. If desired, a pressure gauge 38 may be connected to the pipe 31.

In preparing the equipment for operation, liquid such as water is introduced into the manometer A through the open inner end of the inner stand pipe 33 when no steam is being supplied to the driers 3 and 5, i. e. when the manometer At length, the water level will rise in both the inner stand pipe 33 and in the outer stand pipe 33 to the point 39 where the drain 39 connects with point 39 may be referred to as the neutral point, inasmuch as columns of liquid within both stand

pipes

33 and 33 will stand at the point 39 when the driers 3 are under atmospheric pressure. If more liquid is originally introduced into the manometer A than sufficient to raise the level of the columns of liquid within the two

pipes

33 and 33 to the neutral point 39, the surplus liquid vwill drain of! through drain 39 so that the level of liquid in both pipes will stand at the neutral point 39 under atmospheric pressure.

Prior to using the equipment, valve II will be set by adjustment of thumb nut l3 so as to supply the major portion of the steam for the driers 5 from the main supply conduit 3 through valve ll. Of course, additional steam will be supplied to these driers 3 through by-pass 22 and valve 23, the quantity of additional steam supplied being dependent on the extent to which valve 23 is open at any given time. The steam supplied to the driers 3 from the conduit 6, conduit 3, header 9 and auxiliary conduits III will be dependent upon the extent to which valve 23 in conduit 3 is open. The rider 2311 will be slid along the lever 23 and secured to the lever in a desired adjusted position by the set screw 23b for a purpose presently to appear.

Pin 32 will be plugged into one of the pin receiving openings 33 of the board 33 to set the mechanism for maintaining a desired steam pressure in the driers 3. If it is desired to maintain the driers 3 under low steam pressure, the pin 32 will be plugged into one, of the upper pin receiving' openings. while if it is desired to maintain the driers under higher steam pressure, the pin 32 will be plugged into one of the lower pin Sufficient of the openings 33 are provided at vertically spaced intervals that the pin 32 may be plugged into an opening 33 to maintain the driers 3 under any desiredsteampressurereqinredinproducingall'li IObeen kinds of paper that may be made with the paper making machine.

partitions 36 through the small tubes 31. Inas-- much as the driers '4 are connected to'the header 3 by the auxiliary steam conduits l and the header 9 is in communication with chamber 50 of the manometer through the seen that the same pressure will be maintained at all times within the chamber 50 as is maintained in header 9. It is preferable to provide the header 9 and to connect the same through auxiliary conduits I 0 with several of the driers the header 9 is connected.

As the paper making machine is set in operation, and steam is supplied through the steam conduit 6, both

valves

28 and 23 will remain practically wide open until the pressure of steam within the driers 4 has been built up to close to 2 pounds pressure, the pressure for which the pressure, the pressure within chamber 50 will be correspondingly built up to thereby depress the level of liquid within the outer stand pipe 33 and within the inner stand pipe 34 will such an extent that the liquid will buoy up a considerable portion of the weight of the float 40 thereby relieving the lever 29 of that part of the weight'of the float lifted by the liquid within the inner stand pipe 34. As the weight of the float 40 is relieved from the lever 29, the left end of the lever raises somewhat to cause closing movement of both the valve 28 and the valve 23. At length when suificient steam is being supplied through the valve 28 to maintain the driers 4 under exactly 2 lever 29 will remain approximately stationary to hold valve 28 and valve 23 partially opened. In other words, the rise in the driers 4 will continue until the valve 28 closes sufliciently to continuously supply just the right amount of steam to driers 4 through conduit 6, conduit 8, header 9, and auxiliary conduit ill to maintain driers 4 at the desired pressure for which the mechanism is set. If the pressure within the driers for any reason inner stand pipe 34 and as a result the

valves

28 and 23 will close somewhatto reduce the supply pipe 41, it will be of steam to the driers 4 and thereby lower the pressure therein back'to normal. Similarly if for any reason the pressure of steam within the driers As the valve 28 moves to a more open position or as it moves to a more closed position, the valve 23 similarly opens or closes. As the valve 23 controls the supply of steam through by-pass 22 to the driers 5, it will'be understood that as greater quantities of steam are supplied to the driers 4, greater quantities of steam will be supplied to ,the driers 5 and as less steam issupplied erly adjusting this rider on the lever 24 it is possible to correlate the supply of steam to the driers 4 and 5 so as to cause uniform drying of steam pressure within the driers 4', of course, change as the rate of condensation changes within these driers. If, for example, the sheet carries more water as it passes over the the driers 4, increased steam through the by-pass 22 and valve 23 will be supplied to the driers 5 to remedy the condition in these driers.

It will be seen that there has been provided a simple processand apparatus forsecuring uniform drying of the sheet in previously, it will also carry more words, if conditions arise in the formation of the sheet or in the operation of the machine that would otherwise effect uniform drying of the sheet or efl'eet the uniformity of the moisture content in the sheet at the dry end of the machine, my method and apparatus will quickly adapt the drying cylinders to the changed conditlon, so that at all times the sheet will be uniiormly dried and will contain the desired mois- ,ture content at the dry end of the machine. By automatically regulating the steam supplied to the various driers, the drying capacity of these driers is varied to adapt the driers to the sheet passing over the same; As the steam pressure on the driers 4 rises or falls below a desired constant, the supply of steam to these driers 4 is automatically reduced or raised to bring the steam pressure within these driers 4 back to the desired constant and this is done almost immediately. At the same time steam is supplied in lesser or greater quantities to the remaining driers 5, so as to reduce or capacity of these driers 5 to meet the changed condition of the sheet.

By plugging in the pin 42 in difierent pin receiving openings 43 in the board 44, it is possible to vary the setting of the device so that the constant pressure to be maintained in the driers 4 can be changed to form various types of sheets with the machine. By changing the position of the rider 24a on the lever 24, it is possible to change the proportionate opening and closing movement of the valve 23 relative to valve 28 so as to properly control the steam supplied to the driers 5 relative to the steam supplied to the driers 4.

By provision of the partition 36, the tubes 3] and the drain 38, steam carried over into the upper part of chamber 50 through steam pipe 41 and condensed into water within the chamber 50 will be drained ofi through drain pipe 38, so that the condensation of steam within chamber 50 will not raise the water level within the manometer and change the setting of the manometer. While the partition 36 and the tubes 31 prevent the passage of condensed water downwardly below the partition, the tubes 31 afiord free communication between the diflerent'sections of the chamber 50 above and below the partition.

If at any time during the operation of the machine there should. be a break in the sheet ahead of the driers 4, the steam pressure within these driers will, of course, immediately raise to such a point as to cause the valve 28 to practically completely close and to also cause the valve 23 to practically completely close automatically, thereby preventingwastage of the steam until the sheet again beginsto move over the driers. After the sheet again begins to pass over the driers 4, the manometer remains properly set for proper drying control.

Of course, other mechanisms and apparatus can be used for carrying out my method of securing uniform drying of the paper sheet as it passes over the driersof a paper making machine, and for securing uniform moisture .content in the sheet at the dry end of the machine.

It will, of course, be understood that various changes may be made in my processes and in the steps thereof and in the form, details, arrangement and proportions of the various parts increase the drying of the apparatus without departing from the which, generally.

scope of the present invention, stated, consists in the matter shown and described and set forth in the appended claims.

What is claimed is:

i. In a paper making machine, a plurality of driers over which the sheet passes, a steam line supplying said driers, valve mechanism regulating the supply or steam through said line, a manometer, a conduit communicating a certain section of said driers with the closed end portion of said manometer, afloat mounted within the open end portion of said manometer to be buoyed up by the liquid within the manometer to a varying extent depending on the liquid level within the open end portion of the manometer, and means connecting said float with said valve mechanism to move said valve mechanism to more nearly closed position as said float is buoyed up by the liquid in said manometer to a greater extent and to move said valve mechanism to more nearly open position as said float is buoyed up to less extent by the liquid in said manometer.

2. The structure deflned in claim 1, and means for varying the set level of said float in said manometer.

3. The structure deflned in claim 1, and means for draining on any condensate from steam admitted to the closed end portion of said manometer.

4. In a paper making machine, a plurality of driers over which the sheet passes, a steam line for supplying all of said driers, a main valve controlling the supply of steam through at least a portion of said line, a by-pass around said main valve, an auxiliary valve in said by-pass, a pressure responsive device for operating said auxiliary valve, means connecting said pressure responsive device to a certain section of said driers most closely adjacent the wet end 01 the machine, said pressure responsive device acting to more widely open said auxiliary valve as the pressure in said certain section drops slightly below a certain constant and acting to tend to close said auxiliary valve as the pressure in said certain section rises slightly above said certain constant.

5. In a paper making machine, a flrst group of driers and a second group of driers, said first group being located more closely adjacent the wet end of the machine than said second group, and the sheet passing over all of the driers of both groups, a steam supply conduit, means connecting said supply conduit to said second group of driers, a header, means connecting said header to said flrst group of driers, a second conduit connecting said first mentioned conduit to said header, a flrst control valve in said first conduit, a second control valve in said second conduit, a manometer containing liquid, a tube communicating said header with the closed end of said manometer, a float mounted within the open portion of said manometer and mechanism operating said two valves from said float in such manner that when the float is increasingly buoyed up by the liquid within the manometer said valves will move towards closed position and when said float is decreasingly buoyed up by the liquid within said manometer, the said valves will move towards open position.

ARTHUR E. BROUGHTON.