Lubricating device for lubricating a clothing

Abstract

A lubricating device lubricates a circulating clothing of a machine for manufacturing a fibrous web. The device has a body with a feed chamber that has an inlet for supplying a pressurized liquid lubricant to the feed chamber and an outlet for discharging the lubricant therefrom. The body further has a nozzle chamber to which a nozzle for discharging the lubricant is connected. The nozzle has a flow-conducting connection to the feed chamber via the nozzle chamber and the outlet. Within the body, a diffuser is provided for diffusing the lubricant supplied through the outlet along the body, the diffuser being arranged between the outlet and the nozzle.

Claims

1. A combination of a suction apparatus having a body with at least one suction opening formed therein, and a lubricating device for lubricating a circulating clothing of a machine for manufacturing a fibrous web, the lubricating device comprising: a body including: a feed chamber having an inlet for supplying a pressurized liquid lubricant to said feed chamber and an outlet for discharging the pressurized liquid lubricant from said feed chamber; a nozzle; a nozzle chamber to which said nozzle is connected for discharging the pressurized liquid lubricant, said nozzle having a flow-conducting connection to said feed chamber via said nozzle chamber and said outlet; and a diffuser for diffusing the pressurized liquid lubricant supplied via said outlet along said body of the lubricating device, said diffuser disposed between said outlet and said nozzle; wherein all of said nozzle is formed in said body of the lubricating device, and wherein all of said body of the lubricating device is separate from the body of the suction apparatus.

2. The lubricating device according to claim 1, wherein: said diffuser is disposed within said nozzle chamber; and/or said nozzle extends in a longitudinal direction of said body of the lubricating device.

3. The lubricating device according to claim 1, wherein said nozzle chamber forms or bounds said nozzle.

4. The lubricating device according to claim 1, wherein: said nozzle chamber has a wall; and said diffuser is separate from said wall of said nozzle chamber and is fastened to said wall.

5. The lubricating device according to claim 4, wherein said diffuser is a flat baffle plate.

6. The lubricating device according to claim 1, wherein said outlet of said feed chamber is bounded by or configured as a plurality of openings in a wall of said feed chamber.

7. The lubricating device according to claim 1, wherein said outlet of said of the feed chamber has an opening cross-section dimensioned for the pressurized liquid lubricant in such a way that, viewed in a longitudinal direction, a resulting surface area is 100 to 200 mm.sup.2 per meter of length of said body of the lubricating device.

8. The lubricating device according to claim 1, wherein the lubricating device is configured such that a flow rate of the pressurized liquid lubricant through the lubricating device is 5 to 20 liters per minute per meter of the lubricating device.

9. The lubricating device according to claim 2, wherein said nozzle is configured as a slit nozzle.

10. A configuration, comprising: a suction apparatus having a body with at least one suction opening formed therein; a lubricating device of a machine for manufacturing a fibrous web, said lubricating device including a body, said body of the lubricating device having: a feed chamber with an inlet for supplying a pressurized liquid lubricant to said feed chamber and an outlet for discharging the pressurized liquid lubricant from said feed chamber; a nozzle; a nozzle chamber to which said nozzle is connected for discharging the pressurized liquid lubricant, said nozzle having a flow-conducting connection to said feed chamber via said nozzle chamber and said outlet; and a diffuser for diffusing the pressurized liquid lubricant supplied via said outlet along said body of the lubricating device, said diffuser disposed between said outlet and said nozzle; a clothing; and said lubricating device lubricating a surface of said clothing, and said clothing sweeping along a direction of travel over said lubricating device; wherein all of said nozzle is formed in said body of the lubricating device, and wherein all of said body of the lubricating device is separate from the body of the suction apparatus.

11. The configuration according to claim 10, wherein said lubricating device is set up in such a way that the pressurized liquid lubricant impinges on said clothing in the direction of travel of said clothing.

12. The configuration according to claim 10, wherein said clothing is a felt or a screen of the machine for manufacturing the fibrous web, the fibrous material is selected from the group consisting of paper, cardboard, and a tissue web.

13. The configuration according to claim 10, wherein said lubricating device is set up in such a way that the pressurized liquid lubricant impinges on said clothing in the direction of travel of said clothing at an acute angle.

14. A system of a machine for manufacturing a fibrous web selected from the group consisting of paper, cardboard, and tissue web, the system comprising: a lubricating device including a body, said body of the lubricating device having: a feed chamber with an inlet for supplying a pressurized liquid lubricant to said feed chamber and an outlet for discharging the pressurized liquid lubricant from said feed chamber; a nozzle; a nozzle chamber to which said nozzle is connected for discharging the pressurized liquid lubricant, said nozzle having a flow-conducting connection to said feed chamber via said nozzle chamber and said outlet; and a diffuser for diffusing the pressurized liquid lubricant supplied via said outlet along said body of the lubricating device, said diffuser disposed between said outlet and said nozzle; and a suction apparatus having at least one support strip on which a circulating clothing may be guided, one surface of said support strip is movable relative thereto along a direction of travel, wherein said lubricating device is disposed immediately before said at least one support strip in the direction of travel of the clothing and wherein said suction apparatus has a body with at least one suction opening formed therein; wherein all of said nozzle is formed in said body of the lubricating device, and wherein all of said body of the lubricating device is separate from the body of the suction apparatus.

15. The system according to claim 14, wherein said body, of the lubricating device, has a side facing said suction apparatus, and said side has a shape that is complementary to said suction apparatus.

16. A machine for manufacturing a fibrous web selected from the group consisting of paper, cardboard, and a tissue web, the machine comprising: a suction apparatus having a body with at least one suction opening formed therein; at least one clothing; and a lubricating device including a body, said body of the lubricating device having: a feed chamber with an inlet for supplying a pressurized liquid lubricant to said feed chamber and an outlet for discharging the pressurized liquid lubricant from said feed chamber; a nozzle; a nozzle chamber to which said nozzle is connected for discharging the pressurized liquid lubricant, said nozzle having a flow-conducting connection to said feed chamber via said nozzle chamber and said outlet; and a diffuser for diffusing the pressurized liquid lubricant supplied via said outlet along said body of the lubricating device, said diffuser disposed between said outlet and said nozzle; wherein all of said nozzle is formed in said body of the lubricating device, and wherein all of said body of the lubricating device is separate from the body of the suction apparatus.

17. A machine for manufacturing a fibrous web selected from the group consisting of paper, cardboard, and a tissue web, the machine comprising: at least one clothing; and a system, including: a suction apparatus having a body with at least one suction opening formed therein; a lubricating device including a body, said body of the lubricating device having: a feed chamber with an inlet for supplying a pressurized liquid lubricant to said feed chamber and an outlet for discharging the pressurized liquid lubricant from said feed chamber; a nozzle; a nozzle chamber to which said nozzle is connected for discharging the pressurized liquid lubricant, said nozzle having a flow-conducting connection to said feed chamber via said nozzle chamber and said outlet; and a diffuser for diffusing the pressurized liquid lubricant supplied via said outlet along said body of the lubricating device, said diffuser disposed between said outlet and said nozzle; a suction apparatus having at least one support strip on which a circulating clothing may be guided, one surface of said support strip is movable relative thereto along a direction of travel, wherein said lubricating device is disposed immediately before said at least one support strip in the direction of travel of the clothing; wherein all of said nozzle is formed in said body of the lubricating device, and wherein all of said body of the lubricating device is separate from the body of the suction apparatus.

18. The lubricating device according to claim 1, wherein said body of the lubricating device has a first support strip which when installed in the machine replaces a first support strip of said suction apparatus.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) The invention will be explained in greater detail below with reference to the drawings, without limiting its generality. The drawings show the following:

(2) FIG. 1 a highly schematic side view of a press section of a machine;

(3) FIG. 2 a highly schematic sectional view of a system made up of a suction apparatus and a lubricating device, according to a first embodiment;

(4) FIG. 3 a highly schematic sectional view of a system made up of a suction apparatus and a lubricating device, according to a second embodiment.

DESCRIPTION OF THE INVENTION

(5) FIG. 1 shows a schematic side view, not to scale, of a press section of a machine for manufacturing a fibrous web, such as a paper, cardboard, or tissue web.

(6) The press section comprises a press nip 7 formed by two press rolls 5 and 6. To symmetrically dewater a fibrous web 4, the web is guided through the press nip 7 to be sandwiched jointly between a first clothing 2 and a second clothing 3. Here, the function of the clothing 2, 3, which may be designed as felt belts, consists of receiving the water that exits the fibrous web 4 in the press nip 7. Thus, each belt is in direct contact with the fibrous web 4 on its respective upper side, and with the corresponding press roll 5, 6 on its lower side.

(7) The clothings 2, 3 are designed as continuous belts and circulate around the press nip 7 on corresponding rollers. Past the press nip 7, as viewed in the direction of travel of the belts 2, 3 (from left to right through the press nip 7), the belts must be dewatered. For this purpose, at least one suction apparatus 1 is used, and in this case is designed to be stationary. “Stationary” means that it is stationary from the standpoint of the clothing that moves relative to it.

(8) The suction apparatus 1 will now be described in greater detail with reference to FIGS. 2 and 3, in the context of a clothing. Both drawings show such an apparatus in a cross-section through a plane parallel to the direction of travel of the clothing 2, this plane also thus being perpendicular to the width direction of the clothing 2. In principle, another suction apparatus 1 could be associated with the second clothing 3.

(9) In FIGS. 2 and 3, the clothing 2 rotates from left to right.

(10) The suction apparatus 1 of FIG. 2 comprises at least one inner chamber 8 that may be coupled to a suction source, not shown. Further, a plurality of support strips 9 is provided, which are arranged, with respect to their longitudinal axes, perpendicular to the direction of travel of the clothing 2, 3, and are arranged in parallel and at a distance from each other. The support strips 9 are arranged in a plane that is parallel to the plane defined by the clothing 2, 3. The inner chamber 8 is bounded by a housing 15 of the suction apparatus 1, which is shown only in a detail view here. The support strips 9 are mounted on the upper side of the housing 15, which faces the clothing 2.

(11) The support strips 9 together with their upper sides, which face the lower side of the first clothing 2, jointly form a support surface 14 for supporting the clothing 2. When the suction apparatus 1 is installed, the support surface 14 is directed toward the clothing 2, more precisely toward the lower side thereof. The surface runs parallel to the clothing 2. The support surface 14 here corresponds to the lubrication plane. A plurality of suction openings 13 are provided in the support surface. These openings are bounded, for example, by the support strips 9, which are directly adjacent to the end faces that face one another. The suction openings 13 are connected to the inner chamber 8 in a fluidic, and therefore lubricant-conducting, manner. These openings usually run over the entire width of the clothing 2, or beyond its width. In the present case, the width direction extends perpendicularly in the image plane of FIG. 2, i.e. perpendicular to the direction of travel of the clothing 2 and parallel to the longitudinal axis of the support strips 9. Lubricant, for example water, that has flowed into the inner chamber 8 via the suction openings 13, may be sucked out of the inner chamber via the suction source.

(12) The suction apparatus 1 is associated with a lubricating device 11 in the present case. The lubricating apparatus is arranged in front of a first support strip 9.1, as viewed in the direction of travel of the clothing 2. The “first support strip 9.1” refers to that support strip of the suction apparatus 1 that is first swept by the clothing 2, as viewed in the clothing's direction of travel. Although not shown, a single support plate could also form the support plane, instead of the plurality of support strips arranged spaced apart from one another. The support plate would then have corresponding suction openings 13.

(13) The lubricating device 11 is associated with a body 12, which in this case forms a nozzle 12.6 in its interior for dispensing pressure medium. A reservoir or feed chamber 12.2 is arranged for the pressure medium in front of the nozzle 12.6, in the flow direction of the pressure medium. This chamber is also formed by the body 12. The cross section of the feed chamber 12.2 for the pressure medium is larger than that of the nozzle 12.6, as viewed at least at the mouth thereof. This is because the nozzle 12.6 has a tapering cross section—starting from the feed chamber 12.2—as viewed in the flow direction of the pressure medium.

(14) The body 12 or nozzle 12.6 is arranged in such a way that, during normal operation, it continuously discharges the pressurized lubricant emerging from it onto the lower side of the clothing 2. More specifically, the lubricant is introduced into a lubrication gap bounded by the lower side of the clothing 2 and the support surface 14. The nozzle 12.6 is arranged at an acute angle to the clothing 2 with respect to the longitudinal central axis of the nozzle. As a result, the main application direction of the lubricant exiting the mouth of the nozzle 12.6 substantially corresponds to the direction of travel of the clothing 2. The main application direction thus corresponds to an extension of the longitudinal central axis of the nozzle 12.6 beyond its mouth, on the lubrication plane. By means of such an arrangement of the nozzle 12.6, it is possible for lubricant to flow particularly well into the lubrication gap. The lubricant flows into the lubrication gap even better when the mouth of the nozzle 12.6 is arranged in the vicinity of the lubrication gap, or in or near the lubrication plane. “Near” means that the vertical distance from the mouth to the lubrication plane is a few millimeters.

(15) A targeted introduction of the lubricant into the lubrication gap, and thus improved cooling and lubrication of the clothing 2, may also be achieved because the mouth of the nozzle 12.6 is at the same time bounded or formed by the body 12 and the first support strip 9.1. In such a case, the mouth is also directly in the lubrication gap.

(16) Alternatively, it would be conceivable for the nozzle 12.6 to be bounded or formed by the body 12 alone. The longitudinal central axis of the nozzle could then be at the aforementioned angle to the lubrication plane.

(17) On the lower side of the lubricating device 11, which faces the inner chamber 8 of the suction apparatus 1, this axis has a bent shape. It adapts to the contour of the suction apparatus, which here is designed as a tube sucker.

(18) As further shown in FIG. 2, the body 12 may be associated with a diffuser 12.4. Such a diffuser 12.4 operates as a shutter for the lubricant. For example, it may have a plurality of openings. The diffuser 12.4 serves to equalize the volumetric flow of the lubricant exiting from the outlet 12.5 inside the body 12. The outlet 12.5 is usually realized via a plurality of openings. The lubricant exits these openings in the form of individual jets with high flow velocity. If these individual jets were to reach the nozzle 12.6 directly without the interposition of such a diffuser, an uneven velocity distribution would result at the mouth of the nozzle 12.6 along the longitudinal extent of the body 12. This in turn would mean that the lubricating film runs unevenly over the length of the lubrication gap.

(19) As a result of providing the diffuser 12.4, the individual jets of lubricant, viewed in the lubricant flow direction, first encounter the diffuser 12.4 before the lubricant reaches the nozzle 12.6. The diffuser 12.4 reduces the comparatively high inflow velocity of the individual jets into the nozzle chamber 12.1, with the goal of creating the most uniform flow possible. Thus, by means of the diffuser 12.4, a uniform and uniform-velocity outflow of the lubricant is thus achieved over the entire length of the body 12, and thus a uniform lubricant film thickness is achieved in the lubrication gap.

(20) The diffuser 12.4 may thus be designed in the manner of a baffle plate, for example a flat, quadrilateral belt which extends over the entire width of the nozzle 12.1, and thus at least over the width of the clothing 2.

(21) As illustrated here, the diffuser 12.4 may be arranged in the region of the transition from the feed chamber 12.2 into the nozzle chamber 12.6, and especially inside the nozzle chamber 12.6. It could likewise conceivably be arranged inside the feed chamber 12.2. In any case, the diffuser 12.4 should in any case be arranged at a location within the body 12 where there are individual jets of lubricant having a comparatively high flow velocity, and thus behind the outlet 12.5 as seen in the flow direction.

(22) In principle, two or more diffusers 12.4 arranged behind one another could also be provided in the lubricant flow direction.

(23) FIG. 3 shows a further embodiment of the suction apparatus 1 or lubricating device 11. This is constructed analogously to the embodiment of FIG. 2; the wall 15 and inner chamber 8 are not shown here. Therefore, what has already been said with reference to FIG. 2 applies analogously.

(24) Here likewise, the lubricating device 11 comprises a body 12, with which a feed chamber 12.2 and a nozzle chamber 12.1 for lubricant are associated. The feed chamber 12.2 likewise has a lubricant-conducting connection to a lubricant source, not shown, via the inlet 12.3. Pressurized lubricant is fed to the feed chamber 12.2 and thus to the nozzle chamber 12.1 via the inlet 12.3.

(25) Here likewise, the feed chamber 12.2 and nozzle chamber 12.1 have a flow-conducting connection with one another. This is accomplished via an outlet 12.5.

(26) This outlet is implemented as a plurality of openings, such as through holes, in the wall that separates the feed chamber 12.2 and nozzle chamber 12.1. The openings are distributed over the entire length of the body 12, and thus here in the direction toward the plane of the drawing. Put differently, the outlet 12.5 opens inside the nozzle chamber 12.1. The lubricant exiting from the outlet 12.5 thus passes from the feed chamber 12.2 into the nozzle chamber 12.1, from there into the nozzle 12.6 and from there into the lubrication gap.

(27) Viewed in the lubricant flow direction, a diffuser 12.4 is arranged downstream of the outlet 12.5. This diffuser covers the outlet 12.5 in such a way that the individual jets emerging from the outlet 12.5, or from the openings, collide at the diffuser 12.4.

(28) The diffuser 12.4 extends into the nozzle chamber 12.1 in such a way that both the longitudinal axis of the outlet 12.5 and the longitudinal axis of the diffuser 12.4 intersect in the illustrated section. This ensures that the individual jets of lubricant exiting the outlet 12.5 always collide at the diffuser 12.4.

(29) Because the diffuser 12.4 extends into the flow of the lubricant from the outlet 12.5 to the nozzle 12.6 in this way, the diffuser 12.4, together with the wall of the nozzle chamber 12.1 in which it is arranged, forms a cross-sectional constriction—in the manner of a shutter—for the lubricant. The diffuser 12.4 thus extends only over part of the flow cross-section for the nozzle chamber 12.1 for lubricant. The diffuser 12.4 separates the nozzle chamber 12.1 into two sub-chambers that are connected to one another in a flow-conducting manner.

(30) The lubricant is consequently scattered and homogenized as it passes from the outlet 12.5 to the nozzle 12.6; thus, the diffuser 12.4 reduces the comparatively high inflow velocity of the individual jets into the nozzle chamber 12.1. This makes it possible to achieve as uniform a flow as possible in the region of the mouth of the nozzle 12.6, which ultimately leads to a uniform outflow of the lubricant and thus to a uniform lubricant film thickness in the lubrication gap.

(31) The diffuser 12.4 is designed here as a flat baffle plate. In the present case, it has a surface area that is greater than the surface area of the flow cross-section of the outlet 12.5. This also applies analogously to the embodiment of FIG. 2. As a result, the flow velocity of the lubricant in the region of the mouth of the nozzle 12.6 is particularly well homogenized. It may thus be arranged within the body 12, preferably within the nozzle chamber 12.1.

(32) The diffuser 12.4 may be furnished separately from the body 12, preferably separately from the nozzle chamber 12.1. However, it could also be designed as one piece together with the body 12.

(33) In addition, the diffuser 12.4 could extend over the entire flow cross-section of the nozzle chamber 12.1. In that case, the diffuser could be provided with corresponding openings—similarly to the feed chamber 12.2 with its outlet 12.5. Alternatively, the diffuser could be designed, for example, as a network in order to even out the lubricant flowing out of the outlet 12.5.

(34) As shown in FIG. 3, the lubricant flow cross-section narrows continuously in the lubricant flow direction and opens into the slit-shaped nozzle 12.6. Irrespective of the described embodiment, clogging of the nozzle 12.6 during operation is avoided by this arrangement according to the invention and by the shape of the nozzle. This is facilitated by the fact that the lubricant runs substantially along the direction of travel of the clothing 2, for example at an acute angle. Objects entering the lubrication gap are thus flushed out of the lubrication gap due to both the movement of the clothing 2 and the application of the lubricant. This also applies analogously to the embodiment of FIG. 2.

(35) As shown in the drawings, the body 12 or the nozzle 12.6 may extend over or beyond the entire width of the lubricating device 11, the suction apparatus 1 or the clothing 2. The nozzle 12.6 may be designed so as to create a slit nozzle having e.g. a quadrilateral cross-section as its mouth—as viewed from above the lubrication plane. The mouth may extend over the entire width of the clothing 2 (perpendicular to its direction of travel). Alternatively, a plurality of bodies 12 may be furnished that are arranged transversely to the direction of travel of the clothing and form the correspondingly described nozzles 12.6.

(36) Likewise independently of the embodiment shown, as a general matter, the body 12 on the upper side facing the clothing 2, 3 could have a wearing component (not shown). Such a part may be made of a comparatively softer material than the body 12 itself—for example, a plastic. It serves to avoid damage to the lower side of the clothing 2, 3 in the event of a touch. The wearing component may be replaceable; for example, it may be mounted on the body 12 by means of screws.

(37) If the surface area of the flow cross-section of the outlet 12.5 is dimensioned so that—viewed in the longitudinal direction of the body 12—between 100 and 200 mm.sup.2 is selected per linear meter of the body 12, then there is particularly good lubrication in the lubrication gap. The same applies if the selected flow rate of lubricant is between 5 and 20 liters per minute per linear meter of the body 12.

(38) As a result of the design of the lubricating device according to the invention, this takes up comparatively little space due to its compactness. It may also be retrofitted to existing suction apparatuses without requiring them to be disassembled. At the same time, efficient lubrication and cooling of the clothing may be achieved.