US1757948A

US1757948A - Method and apparatus for making paper

Info

Publication number: US1757948A
Application number: US288367A
Authority: US
Inventors: Claude C Hockley
Original assignee: Individual
Current assignee: Individual
Priority date: 1928-06-26
Filing date: 1928-06-26
Publication date: 1930-05-06
Anticipated expiration: 1947-05-06

Description

May 6, 1930.

.C. C. HOCKLEY METHOD AND APPARATUS FOR MAKING PAPER 2 Sheets-Sheet l Original Filed June 5, 1924 May 6, 1930.. c. c. HOCKLEY METHOD AND APPARATUS FOR MAKING PAPER v Original Filed June 5, 1924 2 Sheets-Sheet 2 172276 CZZZ(73 (lfi oc/tZeg Patented May 6 1930 UNITED STATES PATENT OFFICE CLAUDE C. HOGKLEY, OF PORTLAND, OREGOll 7 METHOD AND APPARATUS FOR- MA KIN 'G PAPER Befile of application Serial No. 717,945, filed {Tune 5, 1924. This application filed June 26, 1928. Seria 5 ing of the web, initspassage over said dryer I section thereby to increase the daily production, and reduce the cost of manufacturing v the paper.

My present application is to'c omplete and more particularly describe the method and apparatus described in my application for Letters Patent, filed June 5, 1924, Serial No.

717,945, entitled Process of making paper.

In making'pap'er, as well-known, it is customary to form the web of the sheet on what is generally called the wet end of the paper machine, and then remove the water, and finally drying the sheet by passing it over one or more steameheated drying rolls.

As the sheet of paper comes to the dryerrolls it has a relatively high moisture content and therefore an eflicient method and apparatus for drying the sheet is essential.

In the ordinary method of drying, the moisture in the sheet is driven out by the heat of the. hot dryer-rolls, and is carried ofi by a natural draft, or chimney, which leads from the hood which covers the dryer rolls.

In this mode of procedure the drying of the paper web was to some extent hastened by passing over the dryer-roll a volume of moving, heated air, thereby to absorb and carry oi the vapors emitted by the web; but it was thought that ample volume of air was suificient, and no attention was given to its velocity, nor the angle at which the sheet of air impinged upon the web of paper.

Furthermore economy in use of heat and power must be taken into consideration; and to accomplish efiicient drying with saving of heat and power is the object of my invention.

' In brief I have discovered that the drying of the web of paper passing over a drying roll may be greatly promoted by impinging upon the web of paper carried by said roll, a relatively thin transverse sheet of air preferably heated moving at high velocity, in the direction of motion of said roll, with said sheet of air constrained to a plane, which if produced, would cut the circumferential surface of said roll and then causing the flow of said air to continue over a substantial longitudinal peripheral section of said roll and finally releasing said air.

My experiments have demonstrated that it will not answer to direct the sheet of air in a plane which would be tan ent to that sec-- web of paper in such manner as to break up n the film of moisture immediately overlying the web, which film if not broken up would tend to insulate the web from the drying air and reduce the effectiveness of the latter. This will slow up materially the drying ef fect of said current of air; on the other hand by breaking up said insulating film of moisture the drying eifect of said current of airis greatly promoted.

In order to carry my 1nvent1on into praotice, I found it convenient to use 1n combination with a drier roll, means for promotingthe drying of the web passed over the roll, comprising a hood open at one end and .ar-. ranged to inclose and form a low passageway over a circumferential section of substantial length of the drier roll, and means for blowing a sheet of air into the other end of said hood at hi h velocity in the direction of the rotation 0 said roll, and in a plane:

which if produced would cut the circumferential surface of said drier roll. Referring now to the accompanying drawings, illustrating my invention and forming part of this specification:

Fig. 1 shows a diagrammatic end elevation of a dryer-roll of a paper making machine embodying my invention; Fig. 2 shows a side elevation of the same; Fig. 3 shows a longitudinal sectional detail of thepressure box and hood covering a circumferential segment of the dryer-roll and by which air is impinged at high'velocity on the dryer-roll and further illustrates means for adjusting the orifices of the airejecting nozzles discharging from the pressure box;

Fig. 4 shows a section taken on the line 4-4 of Fig. 3, and illustrates the manner in which the movable members of said air nozzles are adjustably carried on a pipe or shaft, which is journaled in the ends of the housing of the pressure box; and

Fig. 5 illustrates other means for adjusting the said air-ejecting orifices.

' In the drawings, a designates the outer I casing,'or hood; (1 indicates the main shaft which is suitably mounted, and which carries the dr or roll a, and a is the exhaust by which t e air current is removed after it haspassed under the hood and taken up the moisture, from the section of the paper sheet a carriedby the dryer roll. The arrows in Fig. 1 indicate the direction of travel of the sheet being dried; the entry point of the sheet in the drying apparatus being at a and the exit point at a respectively.

' As shown in Fig. 1, two segments of the dryer roll are provided with my drying meansone on the right the other on the left-the plarts of which means are designatedby t e same reference characters.

6 is the inlet ipe leading from 'a source of air supply un or pressure, and preferably preheated in anyconvenient way; and b is what is known as the pressure box. From this pressure box the air is projected tangentially against thewet paper sheet by the nozzles 6 under the hood 0 as shown in Fig. 3.

Q Each nozzle 7) is constructed to permit the adjustment of its air projecting orifice; and

I prefer to employ, a single nozzle extended across the entire face of the dryer-roll. In-

stead of such single nozzle a suitable closely arranged series of separate nozzles may be provided, but I have not found such an arrangement to work out as well in practical results as by the employment of a single slit type of nozzle. I prefer to use two such long narrow nozzle orifices in the pressure gox, gne above the other as illustrated in The hood a is so arranged with respect to the underlying circumferential segment of the dryer roll as to provide a low passageway thereover, in order that only a relatively thin stratum of air at high velocity will be moved over the paper web under the hood and further will be held in close contact with the circumference of the dryer roll.

The high velocity of the air thus driven through the hood (1 functions to breakup the film of moisture-saturated air that otherwise-. would tend to form a shield over the paper web and reduce materially the speed of its drying.

The air projected by the nozzles is prefer- I ably preheated, and blower (not shown) is used to drive the air through the pressure box at high velocity. And the air nozzles I) must be so arranged as to impinge upon the sheet of air upon the web carried by the drier roll,.in a plane which if produced would cut the circumferential surface of the dryerroll since such accelerates the absorption and effects the rapid removal of the V3.1 pors carried and emitted by the web of paper.

The nozzles 15 are preferably so arranged as to provide a narrow orifice or slit extending across the entire face of the dryer rolls, as already mentioned. The construction is preferably such, also, that adjustment can be made of the orifice from the exterior of the pressure box. My preferred arrangement for this purpose is shown in Fig. 3 and Fig. 4. The lower; part of the nozzle consists of a metal platec', set at a suitable angle and 1 extending the width of the dryer roll as shown, and permanently secured in place. The upper companion nozzle plate (1 is, however, adapted to-be moved with respect to the lower plate, to vary the opening between the two. As shown by Fig. 4 the upper nozzle plate (1 is carried by a series of spiders I), mounted on a common shaft b", journaled in bearings located in the side walls of the pressure box I), with one end of the shaft extending through the side wall; and on such projecting end of the shaft may be provided a wheel" 6, or other suitable controlling means, to facilitate the desired adjustment of the orifices of the nozzles. Set screws e permit the adjustment of said spiders b on the shaft 6 as desired.

In Fig. 5 a modified form of nozzle arrangement is shown.' The upper plate of the nozzle 6 is integral with the bottom of the pressure box, and the lower nozzle plate I) is adapted to be moved and adjusted with respect to the upper plate; the plate I) being carried on a movable supporting bracket secured in place by a bolt 6".

By the employment of my method and apparatus the moisture of the paper may be removed very rapidly, thus reducing the amount of steam used in drying, increasing the productlon; and, in consequence, reducother end of said hood at high velocity upon the web, in a plane which if produced would cut the circumferential surface of said er roll whereby to break up the film of ins ating moisture envelogifig the web of paper.

2. In a paper ma g machine, the combination with a dryer roll of means for promoting the drying of the web of paper passed over said roll, comprising a hood open at one end and arranged to enclose and or'ma low passageway over a circumferential section of said roll, and means includin a pressure box provided with a series 0 nozzles adapted for blowing a transverse sheet of air into the other end of said hood at high velocity upon the web, in a plane which if produced would cut the circumferential surface of said dryer roll, whereby to'break up the film of insulating moisture enveloping the web of paper;

3. In a paper making machine, the combination with adryer roll of means for promoting the drying of the web of paper passed over said roll, comprising a hood open at one end and arranged to enclose and form a low passageway over a circumferential section of said roll, and means including an adjustable nozzle connected to a source of air under pressure for blowing a sheet of air into the other end of said hood at. highvelocity upon the web, in a plane which if produced would cut the circumferentialsurface of said dryer roll, whereby to break up the film of insulating moisture enveloping the web of paper. 4. In a paper making machine, the combination with a dryer roll of means for promoting the drying ofthe web of paper passed over said roll, comprisin a hood open at one end and arranged to inc ose and form a low passageway over a circumferential section of said roll, and means including a nozzle for blowing a transverse sheet of reheated air into the other end of said ood at high velocity upon the .web in a plane which if produced would cut the circumferential surface of said er roll, whereby to break up the film of ins ating moisture enveloping the 'web of paper.

a I CLAUDE Q'HOCKLEY.