JPS58224286A - Drier for moving web - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for drying a moving web, in particular a radiant heater arranged transversely to the moving web, which can be individually controlled to provide a uniform moisture profile. Regarding.

No. 1, filed July 1999, 1979, entitled Transverse Web Dryer.

U.S. Patent Application No. 3 pending with the original U.S. patent application of this application? In papermaking processes where continuously moving sheets of paper are being produced, drying is usually accomplished by means of a cylindrical steam drum, but not from edge to edge, as described in No. 3411. It is known to be non-uniform. If this is done, stripes will appear. This results in a product of uneven quality. Ostrow, both of whom are pending above.
The application discloses efficient 1-positive harvesting of water content variations across a paper web and a 4-control system for efficiently carrying out this purpose. More particularly, this control system operates on the individual dryer modules of the transverse web dryer. The invention discloses and claims the details of the dryer unit itself.

The transverse dryer unit was previously manufactured by Rauskolb
No. 3,29.3,770. Here, q elongated burner units are arranged across the moving web.

Each burner unit then has an individual manually operated valve control so that the burner can attempt to remove dry or wet streaks across the web. The use of infrared heaters to dry textiles, paper, etc., e.g., by the use of fused silica radiant surfaces, is described by Cahn as inventor.
U.S. Patent No. 3. gA'1. ! ;'It, as suggested in No. Here, the heaters can be pivoted about respective axes transverse to the direction of displacement of the web in order to prevent overheating of the web. That is, when the web stops, the heater is pivoted upward.

U.S. Patent No. 3, granted to Zlrrmermann as inventor. Guchi No. 9,232 exemplifies a dryer with a removable heating unit.

Each heating unit has a heating element that has a fused quartz plate at its bottom, adjacent to the moving web pressure that it is drying. The heating module or casing is sufficiently mounted to have gaps such that air flows through the gaps and impinges on the moving web to enhance the drying effect.

Re5search Inc., Minneapolis, Minnesota
, has apparently produced a high density radiant heater for tungsten filament tubular quartz lamps.

A clean quartz window surrounds the lamp to prevent convective cooling of the workpiece or material being cooled by the air cooling of the heater.

In giving an effective dryer unit, the surrounding conditions are:
For example, it goes without saying that this is extremely difficult for paper manufacturing machines.

Thus, for example, a large number of dryer modules with low cost, high strength and high efficiency are provided. It is also desirable that the dryer unit be easily mountable across the width of a relatively large web of moving paper in order to provide an overall drying system that is easily maintainable and not subject to failure. Failure of such equipment is, of course, very serious in the context of paper machines as it may require the entire process to be shut down.

It is therefore an object of the present invention to provide an improved apparatus for controlling the moisture curve of a moving web.

In accordance with the above objectives, the apparatus includes an elongated structural member having a length in the transverse direction at least as large as the web and forming the primary structural support for the dryer apparatus. The support means receives a plurality of dryer modules in side-by-side relationship and removably supports the dryer modules in position across the web for drying the web. The support means is cantilevered from and secured to the structural member.

There is also fixed support means for rotatably supporting at each end a structural member extending towards the web and having therein means for rotating the dryer module away from the web.

FIG. 1 shows a drying device 10 embodying the invention, the drying device 10 being arranged transversely or transversely to a moving paper sheet 11 having a direction of movement indicated by arrow 12. . In the position shown, the dryer unit contained within the device is very close to the moving web 11, e.g. 7 inches (-!j, lIm)
less than Virtual Figure 18 shows the device rotated away from the web to quickly remove the heat source and prevent damage to the individual heating elements in the event of a web break.

As described in the co-pending Ostrow application, the dryer has several components in side-by-side relationship across the paper so that individual bands or slices of paper can be dried to individual specifications. Has individually controlled heater modules. The device 10 comprises several drying units with two heater modules or dryer modules per unit).
168~, including 16g. Of course, the number of units 16 will vary according to the width of the web 4, and the number shown is merely exemplary. Units) 168-16
Each cover for g has a latch metal 298% Z9b to facilitate access to the dryer module.

At each end of the dryer there is a fixed vertical support 188%
Support means 178 and 1? mounted respectively on 18b. There is b. A hydraulic drive system, designated 19, is connected to each end support 1.
It is incorporated into 7a%17b. These, when actuated, rotate the portion of the dryer above the paper away from the paper and back again toward the paper, as shown in phantom FIG. This rotation takes place around a large diameter elongated structural member in the shape of a circular conduit, shown in phantom at 21. Square shaped members or other equivalents may also be used. The entire pivoted device is
It is cantilevered around this structural member which serves as the primary structural support for the drying equipment. The ends of the structural members are thus journaled in bearings in the end pieces 178.degree. 17b.

Each hydraulic actuator unit) 19 includes a cylinder z2 fixed to an end support at a pivot point z8. The end 24 of the actuator is pivotally connected to the central portion 1B of the drying device. End 26 shows the piston in its extended condition.

In addition to serving as the main structural support of the drying device, the hollow member z1 also acts as a conduit for electrical wiring within the device.

Cooling air is provided by forced air blowers 27 connected by hoses 28 to seven of the end panels. In practice, either end gloss panel may be suitably used to introduce air into the dryer units 16a-16g; ) to form an enclosed structure.

Figure 2 shows the broken unit) 16g cover 20,
Another portion of the individual heater modules 81 is shown; these are supported by a pivoted structure and are replaceable to facilitate repair. The hydraulic actuator 19 is pivotally connected at 24 to the end wall 41 of the central section. The same structure is at the opposite end lea.

Module 81 includes a pair of electrical conductors 82 extending outwardly from a through hole 84 in structural member 21 to the heater module itself;
813, etc., and are individually powered and controlled as detailed in the co-pending ostrow application. This electrical conductor has a typical power output of an individual heater module of % lIgOI,
Since it is 21 I kilowatts, it is quite a remarkable size.

Thus, obviously, in addition to its structural support function, the capacitor 21 Vi also supports and cools (via the through holes 84) the electrical conductors that supply energy to the dryer module.

End support 1? To insulate ax 17b from heat, the pivoting central section has a plank 42 of insulating material at each end.

The central portion of the dryer is pivoted so that a pair of bearings 86a, 86b are attached to the ends 178,1? b. The bearing is shown in detail in FIG. 3, where the fixed bearing support provides a mounting block 88 for wall 8
7 and on top of the mounting block 88 a bearing strip 89
is concluded.

The bearing itself is sintered brass, for example a typical journal sleeve bearing.

FIG. 9 is a cross-sectional view of the entire drying unit, illustrating how the device is effectively secured to and cantilevered onto the main structure 21. Furthermore, it allows the dryer modules 81 to be interchangeably supported in side-by-side relationship. To be more specific, the feather-shaped support part 4B
and 44 extend from the structural member 21 and are welded to the structural member 21. The lower portion 44 has a shelf 41 on which one end of the heater module 81 rests and is visible. The opposing shelf portion 47 has partially cut away spaced brackets 4 shown in dashed lines.
8 and the bracket 48 is fixed to the vane bracket 48.

These are spaced apart, for example, every lIth unit 16. Between the shelf areas 46 and 47 there is an open space for a quartz lamp heater 51, each of which contains several dryer units 37, acting on the paper directly below it. The quartz rung heater 51 of the heater module 81 has an axis that coincides with the direction 12 of the moving web (FIG. 7). The rung is energized by striking terminals 52 and 58 connected across heater 51 and conductor 3z. A third electrical conductor 85 provides a safety ground connection.

The top of each dryer module is a recessed plate 54 with a number of holes 55 (see FIG. 2) that admit air into the blennium chamber 56. Arguably, air is supplied by a forced air pro-assistance system through the main air plenum 80. Blenheim 56 1 has its bottom side formed by a slotted ceramic plank or tile 57, best shown in FIG. There, there is a ceramic board 57Vi with 0 slots, which has almost the same number of slots as a quartz rung heater, and a ceramic interlocking block 5.
Both these ceramic blocks and the tiles themselves can be constructed from materials such as alumina.

Additionally, air is picked up by scoops 49 and 50 (see FIG. 2), which direct the air toward opposite ends 51 of quartz heater 51 as shown by the arrows. lamp 51
The ends must be kept cooler than the main body, as they are the first points of failure. The scoop ensures proper air flow.

The quartz plate 6υ closes the bottom of each heater module 81. The quartz plate 60 is actually divided by a slit 65 formed in the center line of the plate 60 parallel to the heater element 51 into the lower molecules lOa and 60b, as best shown in FIG. . Furthermore, since the quartz plate 60 is held only at its ends by the U-shaped end pieces 6z and 68 as shown in the figure, a slit 66 is formed between the plates of adjacent heater modules. slits 61 and 6
6 allows cooling air to escape into the space between the sheet material 11 and the quartz plate 60 and then exit from the front and rear of the module 81 as indicated by the arrows in FIG.

As partially depicted in FIG. 9, an optical coating 64 may be applied to either side of the fused silica plate 60 to reduce or eliminate the amount of visible light. This is for the benefit of nearby workers, who, without this optical coating, might be adversely shadowed or bothered by visible light. Although only seven centerline slits 61 are shown in the quartz plate, depending on the application, two or more slits with wider or narrower widths may be used to provide the correct airflow and backpressure. I can do it.

The above configuration has several advantages. It allows cooling air to be vented from the quartz rungs and utilizes this vented air to provide relatively cool air to the moving web and heating module openings. In other words,
Relatively cool air is provided between the paper and the heater module. In this case, as shown in FIG.
This is to constantly blow it away from the surface of 1. There is also a security purpose to keep the web away from hot heaters, thus reducing the risk of fire. The glass plate prevents the paper or web material from hitting the heater element, which, depending on its type, may have high mechanical strength. Finally, back-flow pressure allows the plenum 56 to provide uniform distribution of air to all modules 81.

Depending on the application, for example, if the heating element does not require impulsion, the glass plate can be completely removed to allow free flow of air from the quartz lamp to the paper sheet.

FIG. 6 shows a cross section of a heater module having a recessed top plate 54 with holes for admitting air into the plenum 56, where the air enters the plenum 56 after being homogenized through the plenum. Flows equally well through all of the slots 58 in heater tile 57'. Several tubes or lamps 51ti of the quartz heater are offset by an amount i from the slots 58 and therefore do not receive a direct air flow over them. Furthermore, this deviation means that the radiant energy is 1 line of sight
' through the slot to prevent transmission to the Blenheim chambers 5 and 6. This air, of course, provides cooling for both heater enclosures, which themselves, being quartz, do not absorb much of the radiant energy except enough to still require cooling.

Figures 7 and 3 show another embodiment of the heating element, now designated 51'. As described in conjunction with FIG. 7, air scoops 49 and 50 are used to specifically direct air to cool the ends of the heater elements. Cooling of these parts of the heater element has been found to be important as they are exposed to high temperatures. As shown in FIG. 9, the heater element is capped with a standard box enclosure available from the manufacturer.

However, as shown in Figure 7, these enclosures are
Now only the narrowed flat end 67 of the heater element has been removed. These ends are held by clips 68. And the insulation sleeve? An electrical conductor 69, protected by l, extends from each end.

Air flows, for example, from one air scoop as shown by arrow 7z. Tube 61 with respect to narrowed flat portion 67
It is believed that due to the constriction (constriction) caused by the central portion of the air, a Venturi-type effect accelerates the air flow rate or air volumetric flow rate. Therefore, the critical ends of the heating element are cooled more effectively. And this is also true, as noted above, because in standard end-caggage systems, the end 67 is now substantially fully exposed to cooling air. Clip 68 covers only a small portion of the surface area of end 67 to provide better cooling?
Note that it is covered.

Another modification made in the embodiments of FIGS. 7 and 3 is that the insulating heater tile 57 (FIG. 6) has removed the slot 58, as best shown in FIG. It has been modified to provide a solid bulkhead 57'. This therefore directs substantially the entire flow of air from the plenum 80 (fully enclosed and extending across the structure, see FIG. 7) through the air scoops 49 and 50 first to the heater element 51. ' over the end 67 and then over the heater element itself.

Then, of course, as mentioned above, the quartz protection plate 60 includes slits 65 and 66 (FIG. 6) to allow cooling air to escape into the gap between the paper 11 and the plate 60. There is.

Since the tile 57' is now solid, the blenheim chamber 56 shown in FIGS.
It is advantageous to make the plate 54 solid without holes 56.

Thus, in summary, the use of a cantilevered structural member 21 to support the remainder of the dryer greatly simplifies the construction of the dryer unit. Moreover, any individual dryer module 81 can be quickly replaced by simply opening one of the single Fc covers 20 and removing the electrical connections. Since the individual quartz heat lamps are held by clips at each end, the quartz heat rungs are easily removed when the heater module is outside the frame. Finally, due to the air circulation through the heater module, the remainder of the drying equipment helps to even out the temperature, prevent hot spots, and generally help extend the life of all components.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a device embodying the invention, showing its installation on a paper machine. Figure Ω is a partially cutaway enlarged top view of a part of the @/ figure. FIG. 3 is a partial cross-sectional view taken along line 3--3 in FIG. FIG. 7 is a sectional view taken along the line of the goo in FIG. FIG. 3 is a top view of the heater module portion taken along the left-hand line -5 in FIG. 4. FIG. 6 is a partial cross-sectional view taken along line 6-6 in FIG. FIG. 7 is a partial perspective view showing another embodiment of the present invention. FIG. 5 is a partial sectional view of another alternative embodiment, but similar to FIG. 9. lO...Drying device, 81...Dryer module,
Heater module, 21... Structural member, l? a, 17
1)... Support means, 188% 181)... Fixed vertical support, 80... Main air gap, 56...
- Blenheim chamber, 65... slit, 66... slit, 57'... bulkhead, 51'... heater element.

Claims (1)

[Claims] (1) In a moving web drying device: a plurality of elongated structural members having a length in the transverse direction at least as large as said web and forming a strut force structural support for said drying device; dryer module; support means for receiving the dryer module in side-by-side relationship and for removably supporting the dryer module in position across the web for drying the web, the support means comprising: , cantilevered from and fixed to the structural member; and having means therein for rotating the dryer module toward and away from the web; (2) In a moving web drying device: a device for drying a moving web comprising: rigid support means for rotatably supporting a structure at both ends; an elongated structural member having a length of the same magnitude, carrying a plurality of side-by-side heater modules for drying the web, and including an upper air plenum coupled to all of the heater modules; to the air plenum; forced air cooling means for supplying cooling air; and a plurality of spaced apart parallel elongated heater elements proximate said web, each dryer module having said heater element and said web connected to each other. a solid bulkhead substantially transparent to the heat-generating radiation of the heater element supported by the dryer module between the web and the bulkhead; a moving web drying apparatus comprising: at least seven narrow slits in the bulkhead parallel to the heater element to allow passage of air from the air plenum.