US1951714A - Method of and apparatus for making paper - Google Patents

Description

March 20, 1934- J. D. TOMPKINS 1,951,714

' rmzmob OF Ann APPARATUS FOR MAKING PA-P'ER Filed Aug. 11, 1951 Y ATTORNEY Patented Mar. 20, 1934 DIETHOD OF AND APPARATUS FOR MAKING PAPER John D. Tompkins, Valatie, N. Y. Application August 11, 1931, Serial No. 556,436

16 Claims.

This invention relates to an apparatus for and a method of making paper.

One object of my invention is to better preserve the paper fibre bond in a'newly formed paper web, together with forming a "set in the component parts of the web.

Another object of my invention is the provision of a device for the extraction of water from the newly formed paper web in the wet section of a paper making machine prior to its passage between the press rolls.

To the accomplishment of the foregoing and such other objects as may hereinafter appear, this invention comprises the construction, combination and arrangement of parts and the method hereinafter described and then sought to be defined in the appended claims, reference being had to the accompanying drawing forming a part hereof, and which shows, merely for the purpose of illustrative disclosure, a preferred embodiment of my invention, it being expressly understood, however, that various changes may be made in practice within the scope of the claims without digressing from my inventive idea.

In the drawing:

Figure 1 is a central vertical sectionalview showing diagrammatically the invention applied to Fourdrinier machine.

Figure 2 is a similar view showing a modification of the invention.

Referring now to the drawing, the reference numeral 1 designates a forming wire which passes around lower couch roll 2. The lower couch roll 2 is adjacent to and co-operates with the upper couch roll 3, and the upper or top felt apron 4 passes therebetween. Positioned beneath the forming wire 1 are the suction devices 5 which co-operate with the elongated electrical heating devices 6 provided with reflectors '7. It is to be noted that the heating devices are positioned so that they heat the wet paper web 8 on its top surface and also heat the air above the paper web before suction is applied beneath. By so heating the newly formed paper web 8 a pre- 5 liminary set is formed, and the paper web 8 is then carried through the apparatus more easily. The top or upper felt passes over the roll 10 and a portion of the upper felt overlaps the forming wire 1.. A heater 11, reflector 13 and suction device 15 are provided between the couch rolls and the roll 10 so that heat and suetion are applied to the web 8 while it is held between the top felt 4 and the forming wire 1. Rollers 9 are provided for supporting the formins wire 1.

After the paper web 8 leaves the couch rolls 2 and 3, it is attached to the upper or top felt 4, and is guided by the roll 12 and then passes over a suction roll 14. The lower felt 16 passes around the suction roll 14. the roll 14 is so positioned that suction is applied to the wet lower felt just prior to the time that the wet paper web 8 is conducted to the lower felt. However, suction is also applied to the newly formed paper web 8 and the top felt 4 adjacent 35 this point. The paper web 8 is carried between top felt apron 4 and bottom or lower felt 16, and is then subjected to the heating action of the electrical heaters 20 and 21 and suction devices 22. Reflectors 23 and 24 are provided for heaters 20 and 21. Air is drawn through the lower felt prior to its contact with the paper web.

The paper web 8 and the top and bottom felts are then conducted between upper press roll 25 and lower press roll 26. A gutter 27 is provided beneath roll 26. The paper web 8 is attached to the upper or top felt apron 4 and is conducted to the drier 28. The top felt passes over a pressure roll 30 which presses the top felt 4 and the paper web against the drier 28. The upper felt 8Q then passes. over idler rolls 32 and 34, while the paper web 8 has been transferred to the drier 28. A calender roll 36 is provided to smooth the paper on the drier 28 after it has left the top felt apron 4. A scraper 38 is provided for the calender roll 36 to remove any adherent paper particles. The paper web 8 is then conducted to another drier 40. The number of driers is optional, and the invention is not to be restricted to the actual number shown in my preferred embodiment. A scraper 42 is provided for the first drier 28.

After passing between the press rolls 25 and 26, the lower felt 16 is passed over a plurality of idler rolls 46. Before the lower felt reaches the suction roll 14, it is subjected to a water spray from the shower pipe 48, and to a beating action by the beater 50. The top felt apron 4 is likewise provided with a shower pipe 52, and a beater 54. A suction device 56 is positioned beneath the top felt apron 4 to remove excess moisture from the felt after it has been subjected to the water spray. I

The modification shown in Figure 2 is similar to the form shown in Figure 1 with the electrical heaters omitted. -As the devices operate in substantially the same manner, it is not believed necessary to give a detailed description of the modification shown in Figure 2. The same reference characters are applied to the parts of the no The suction element 18 of 5 formed paper web from being weakened by unsupported undulations and stretching is to preserve its paper web strength in its original fibre bond formation.

The operation of my invention will now be described. The paper is deposited on the forming wire 1 and is subjected to radiated heat from the electrical heating devices 6 on the top of the paper web 8. This heat is applied in advance of the suction from the suction boxes 5 positioned beneath the forming wire 1 so that some water is vaporized and the air above the paper web 8 is heated before being drawn through the web. The top felt apron 4 overlaps a portion of the forming wire 1, and radiated heat and suction are applied to the paper web 8 carried between the top felt and the forming wire 1 before the paper web 8 is carried between the couch rolls 2 and 3. The paper web 8 is'then carried between the couch rolls 2 and 3 where it is compacted by light pressure and adheres to the top felt. The paper web 8 is automatically carried along by the top felt, and is then carried between the top felt apron 4 and the lower felt 16, over the suetion roll 14, without undulations or stretching. The paper web 8 is then carried between these felt aprons and is again subjected to radiated heat applied to the top felt by means of the electrical heaters 20, and suction from the suction boxes 5 positioned beneath the lower felt 16. After this treatment, the paper web 8 is carried through the press rolls 24 and 26, and while still adhering to the top felt apron 4 is carried to the drying section of the machine, including the driers 28 and 40.

In practice, the lower felt apron 16 is wet due to the fact that it has been showered in its return course by the shower pipe 48. It is desirable to remove some of this moisture before the lower felt apron contacts the newly formed paper web 8. When the wet paper web 8 with the wet lower felt apron 16 pass together between the press rolls 25 and 26, the water is removed if the device is operated at a relatively slow speed. The water is absorbed by the lower apron 16, and passes into the drainage gutter 2'7 provided beneath the lower press roll 26. If the speed of the device is raised, the increased rush of water tends to displace the paper fibres and gauls the paper web 8. In order to prevent these objectionable features which are encountered when the device is run at high speeds, I prefer to reduce the quantity of water expressed at the press rolls 24 and. 26 in the following two ways. First, I reduce the amount of water in the newly formed paper web 8 while it is on the forming wire 1 by employing a series of hot air reflectors above the paper web 8 with a co-operating suction device beneath the web, and, second, I reduce the amount of moisture in the lower felt apron 16 by suction prior to its contact with the newly formed paper web 8 by means of the suction roll 14.

I have discovered that by causing a current of hot, dry air to pass through the body of the interposed newly formed paper web 8 that I not only reduce the amount of moisture in the paper web 8 before it reaches the press rolls, but that I also start in the paper web 8 the form of a set that will hold the parts together, that prevents fouling the lower felt 16, and saves paper stock, and at the same time produces an improved product. To safeguard this set begun in the paper web 8 on the forming wire 1 when it reaches the lower felt apron 16, I find it advantageous to em ploy a suction roll 14 in conjunction with the lower felt apron 16, the suction roll having a portion of its suction area applied to the lower felt apron to extract water therefrom in advance of the lower felt aprons contact with the paper web 8. If this were not done, the action of the wet lower felt apron 16 would retard or be detrimental to the set begun in the paper web 8 on the forming wire 1.

From the foregoing it will be apparent that my invention provides a means of and a method for producing better paper at a cheaper cost.

What I claim is:

1. A process of making paper, which comprises, heating a newly formed paper web while applying suction thereto on a forming wire, transferring the paper web to a traveling felt apron, and applying suction to the felt apron prior to its contact with the paper web so as to remove excess moisture from the felt.

2. In a paper making machine, the combination of a forming wire to receive a newly formed paper web, heating means for said paper web, a top felt, a lower felt, a suction roll about which said lower felt travels, said suction roll being so positioned as to extract moisture from the lower felt in advance of the contact of the lower felt with the newly formed paper web.

3. In a paper making machine, the combination of a forming wire with heat reflectors above said wire, a top felt, a lower felt, couch rolls for said top felt and said forming wire, a suction roll for said lower felt, and press rolls, the suction roll being positioned between said couch rolls and said press rolls for removing moisture from said lower felt.

4. In a paper making machine, the combination of a forming wire for conveying a newly formed paper web, a top felt extending over a portion of said forming wire, a lower felt, a suction roll for said lower felt, and press rolls, the suction roll drawing hot air simultaneously through said lower felt, top felt, and the newly formed paper web to remove moisture therefrom in advance of said press rolls.

5. In a paper making machine, the combination of a forming wire for receiving a newly formed paper web, a top felt, a lower felt, a suction roll for said lower felt, press rolls, and a dryer roll, the top felt being adapted to carry the newly formed paper web on its under side from the forming wire to the lower felt, over the suction roll, through the press roll to the dryer roll without stretching, or unsupported undulation, substantially as described.

6. In a paper making machine, the combination of a forming wire, a top felt, a lower felt, a suction roll, press rolls, a succession of heat reflectors adjacent the top felt and positioned between said suction roll and said press rolls.

'7. A process of making paper, which comprises, heating anewly formed paper web while applying suction thereto on a forming'wire, transferring the paper web to a traveling lower felt apron, and

1,951,714. a It removing moisture from the felt apron prior to its contact with the paper web.

8. In a paper making machine, the combination of a forming wire for conveying a newly formed paper web, heat reflectors above said paper web, a top felt, a lower felt, and means for removing moisture from said lower felt in advance of the contact of said lower felt with the newly formed paper web.

9. The method of making paper, which oomprises, applying radiated heat and suction to a paper web on a forming wire and then applying heat and suction to the paper web while passing between the forming wire and an upper felt before subjecting the paper web to mechanical pressure.

ill. The method of making paper, which oomprises, applying rad ated heat and suction to a paper web on a forming wire, the heat being applied in advance of the suction to preheat the air above the paper web and then applying heat and suction to the paper web while passing between the forming wire and an upper felt.-

11. The method of making paper, which comprises, applying radiated heat and suction to a newly formed paper web on a forming wire to form a set in the paper web, applying heat and suction to the paper web while it is held between the forming wire and an upper felt, and then applying radiated heat to the paper web while it is held between felt aprons.

12. A process of making paper, which comprises, heating a newly formed paper web while applying suction thereto on a forming Wire, transferring the paper web to a traveling felt apron, and drawing heated air through the felt apron prior to its contact with the paper web so as to remove moisture from the felt.

13. In a paper making machine, the combination of a forming wire, heat reflectors above said wire, a top felt, a lower felt, couch rolls for said top felt and said forming wire, suction means for said lower felt, and press rolls, the suction means being positioned between said couch rolls and said press rolls for removing moisture from said lower felt prior to its contact withthe newly formed paper web.

14. A process of making paper, which comprises, heating a newly formed paper web while applying suction thereto on a forming wire,;

transferring the paper web to a traveling lower felt apron, and drawing air through the felt apron prior to its contact with the paper web so as to remove moisture from the felt apron.

15. The method of making paper, which cornprises, applying radiated heat and suction to a newly formed paper web on a forming wire to form a set in the component parts of the newly formed paper web, applying further radiated heat and suction to the paper web while being carried between an-upper and lower felt apron to augment the set in the component parts of the web prior to subjecting the web to mechanical pressure.

16. The method of making paper, which comprises, applying radiated heat and suction to a newly formed paper web on a forming wire to

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