US 3613999 A
Description (OCR text may contain errors)
United States Patent [72} Inventors Thomas P. Bentley Wilmington;
Donald F. Miller, Newark, both of Del.  Appl. No. 32,979  Filed Apr. 29, 1970  Patented Oct. 19, I971  Assignee E. l. du Pont de Nemours and Company Primary Examiner-M. Henson Wood, .lri
Assistant Examiner-John J. Love Attorney Howard P. West, .lr.
ABSTRACT: An apparatus for jetting high-pressure liquid streams into fibrous materials that includes a quick change cartridge device loosely fitted into a body member. The cartridge includes an orifice plate to produce the liquid streams and a filter between the source of pressurized fluid supplied to the jet and the plate. A seal between the cartridge and the jet body relies on internal operating pressure within the jet body to effect sealing action.
awmnn 5 5wb9m 53 2 0 26 9 T 6 5 N 45 0 mm m m U m .& Q m mm I L m :5 G m mm N m :5 I n m WW3 L m mml mw m mmfi m FTw SAr m we UMD S m mw MUm m NB O l L0 mmwm .m P .w Afl6 U .mF 4 H UN 5 w B5 PATENTEBnm 19 l97l sum 2 Or 2 BY M ATTORNEY APPARATUS FOR JETTING LIQUID ONTO FIBROUS MATERIAL BACKGROUND OF THE INVENTION This invention relates generally to a hydraulic entangling process for a randomly oriented fibrous web and more particularly, to improvements in the jet apparatus used to generate the high velocity liquid streams used for entangling the web.
Hydraulic entangling methods such as passing a layer of fibrous material on the suitable support under high-pressure liquid streams, formed by a row of orifices in ajet manifold are known. One such jet arrangement, which involves the use ofa manifold body into which high-pressure liquid is admitted and includes an orifice strip sealed in place by a slotted retaining plate secured to the manifold body by two rows of bolts extending the length of the manifold is disclosed by Dworjanyn in U.S. Pat. No. 3,403,862. Jet arrangements of this type have the disadvantages of requiring high maintenance time for changing the orifice strip and readily obtaining an effective metal-to-metal seal between the body, the orifice strip and the slotted retaining plate without damaging the jet orifice strip. The down time required to change the orifice strip of such prior art arrangements is proportional to the number of bolts that must be removed and then uniformity retightened to apply substantially equal sealing pressure around the orifice strip after it has been replaced.
SUMMARY OF THE INVENTION It is an objective of this invention to provide an improvement in a jet apparatus for entangling wide widths of fibrous material wherein the orifice strip of the jet may be quickly and easily changed while maintaining the sealing efficiency of the seal between the orifice strip and the jet body.
This objective is achieved in an apparatus that includes an elongated body member which has a chamber running substantially the full length of the body. The chamber, preferably,
is rectangular, defined by upper, lower and sidewalls and sealed at each end by removable closures. A loosely fitting elongated cartridge is positioned in the chamber. The cartridge has an open portion facing upward and a wall with a row of orifices facing downward in alignment with a slot through the body. Means for sealing around the slot between the cartridge and the lower wall is preferably in the form of an O-ring seal in the bottom of the cartridge which seals under the force of the downward pressure of fluid supplied through the upper wall of the chamber. The end of the cartridge which enters the chamber first is fitted with a slide whose height extends beyond the O-ring in the cartridge bottom to prevent damage to the O-ring as the cartridge is inserted in the chamber. At the far end of the chamber, the slide falls into a relief groove when the cartridge is properly positioned and only then does the O- ring come into full contact with the lower wall of the chamber.
BRIEF DESCRIPTION OF THE DRAWING FIG. I is an elevation view of the jet apparatus of this invention being used to entangle a fibrous material.
FIGS. 2 and 3 are partially sectioned elevation views of each end of the cartridge that is positioned in the jet body.
FIG. 4 is a section of FIG. ll taken along 4-41 with parts separated for clarity.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIG. 1, the jet apparatus of this invention is supplied with high-pressure liquid through pipe 12 and, in turn, impinges liquid streams M on a fibrous layer 16 being passed beneath thejet on a conveyor 18.
As shown in FIG. 4, the jet apparatus 10 includes as the major elements thereof an elongated jet body 20 and a cartridge 50 positioned in the body. The body 20 includes an upper portion 22 and a retainer cap 24 secured to it by two rows of bolts 26. Contacting surfaces 28, 30 of the body are sealed with an elastomeric O-ring 32. When assembled, portion 22 and cap 24 form a chamber 23 within jet body 20 defined by upper, lower and sidewalls 36, 38 and 40, respectively. Chamber 23 extends substantially the length of the body 20 and is sealed at each end by removable closure caps Ill, 13 bolted to the ends of body 20 (FIG. 1). Continuous slot 25 leads out from chamber 23 through wall 38; the slot is closed at both ends. The upper body portion 22 has a cylindrical passage 34 running lengthwise through it to which highpressure liquid is supplied via pipe 12 (FIG. I). A number of distribution holes 42 serve as outlets for passage 34 and lead downwardly into chamber 23. As shown, a tube filter 35 may be positioned in passage 34.
Cartridge 50 includes a channel-shaped member 52, a jet orifice strip 54 and a filter 56 clamped to member 52 by means of retainer 57 and bolts 59. The channel member is closed at each end with its open portion facing upward and has a closed slot 58 through its bottom wall. Jet strip 54, perforated with a row of small holes 55 along its longitudinal axis rests on the inner bottom surface of channel member 52 on a flat elastomeric seal 60. Embedded in a groove on the outside bottom surface SI of channel member 52 is a continuous elastomerie O-ring 53 which contacts lower wall 38 of chamber 23 when the cartridge is in position.
The cartridge 50 fits very loosely in chamber 23, that is, there is clearance between the cartridge 50 and the upper and sidewalls 36, 40 of the chamber. This particular structural relationship allows the cartridge 50 to be surrounded by pressurized liquid from all sides except the bottom. A slight in balance of pressure forces exists in the horizontal direction due to the thickness of the bottom channel member 52. This results in a force component which keeps member 52 from spreading and insures uniform support for orifice strip 54 along the inner bottom surface of the channel member.
As shown in FIGS. 2 and 3, cartridge 50 is nonsymmetrical with respect to its ends. One end has a pressure connection in communication (via passage 72) with the area right above jet orifice strip 54 to permit pressure measurements above the strip (FIG. 3).
The opposite end of cartridge 50 (FIG. 2) is fitted with a Teflon slide 74 having a vertical height that extends downward beyond O-ring 53 in the bottom surface of the cartridge. The cartridge is inserted into chamber 23, slide first, which prevents the O-ring 53 from rubbing the lower wall 38 of the chamber. At the end of the chamber is a relief groove 75 in wall 38 to accommodate slide 74. When the cartridge is properly positioned in the chamber, slide 74 drops into relief groove 75 and O-ring 53 then comes in contact with lower wall 38. When the cartridge 50 is removed, the slide 74 comes out ofits groove 75 and, in turn, lifts the O-ring. The slide also serves as a wiper which cleans the sealing surface of wall 38 of dirt particles which may interfere with proper sealing.
The benefits of the quick change cartridge are quite evident and include the saving in equipment-down time as well as reduction in labor required to change a jet orifice strip that may have become plugged during operation. Sealing between the orifice strip and channel member of the cartridge and between the cartridge and the lower wall of the chamber is established as soon as a sufficiently high flow of processing liquid is obtained to result in a few hundred p.s.i.g. pressure in crease inside the jet assembly. Further, there is no need for initial compression between the surfaces sealed.
The quick change feature of this invention has been successfully demonstrated to reduce maintenance time required to change an orifice strip by an order of magnitude. Before,
the entire jet assembly had to be removed and completely disassembled. Now, the jet cartridge after removal of end closure 11 can be quickly changed with a pretested replacement.
What is claimed is: 1. An apparatus for jetting liquid onto fibrous material comprising: an elongated body, there being a longitudinal chamber in said body, said chamber extending through at least one end of said body and having upper, lower and sidewalls, there being a slot through said body from said lower wall; an elongated cartridge positioned in said chamber said cartridge resting on said lower wall and having an open portion facing up ward and a wall facing downward,having a longitudinal row of 5 orifices therethrough, said row being aligned with said slot, said orifices being in communication with said open portion; means for sealing around said slot between said cartridge and said lower wall; a removable closure attached to said one end for sealing said chamber; and means for supplying pressurized fluid to said chamber through said upper wall.
2. The apparatus as defined in claim 1, including a first filter positioned adjacent to and above said row of orifices and a second filter positioned between said means for supplying pressurized fluid and said upper wall.
3. The apparatus as defined in claim 1, there being clearance between said cartridge and the upper and side walls ofthe chamber.
4. The apparatus as defined in claim 1, said cartridge having a bottom surface resting on said lower wall, said means for sealing being an O-ring seal attached to said bottom surface, said seal extending out from said surface.
S. The apparatus as defined in claim 4, including a slide attached to said cartridge at one end, said slide extending outward from said bottom surface beyond said seal, there being a recess in said lower wall at the other end of the chamber for accommodating said slide when said cartridge is in position in said chamber.
6. The apparatus as defined in claim 4, said seal being an elastomeric seal.