US2245109A - Felt cleaner - Google Patents

Description

June 10, 1941. L, LAPEYRQUSE 2,245,109

FELT CLEANER 2 Sheets-Sheet 1 Filed March 1, 1938 Lafwyraue `June 10, 1941. L. l.. LAPEYRousEJ FELT CLEANER Filed March 1, 1958 2 Sheets-Sheet 2 /3 f/` Zd, I g /ew Patented June 10, 1941 UNITED STATES PATENT oFEicE FELT CLEANER Lawrence L. Lapeyrouse, Chickasaw, Ala.

Application March 1, 1938, Serial No. 193,373

1 Claim.

This invention relates to devices for cleaning the endless felt or woolen yblankets used between the press rolls of a paper making machine where the felt acts as a conveyor belt for the wet sheet of paper andralso as a medium through which water that is pressed out of thevsheet passes onto the suction roll. I'hese endless belts become dirty or filled up by small fibres adhering to them and they also require cleaning because a certain amount of rosin size, alum, starch, coloring matter and other ingredients are deposited on these felts.

A structure for cleaning these felts is shown and described in my Patent No. 2,043,415, granted June. 9, 1936, and the present structure illustrated in the accompanying drawings is an improvement upon the structure of the cleaner shown in said patent.

In the patented cleaner, there is illustrated a vacuum headI over which the felt belt passed, this vacuum head having extending across it a plurality of rollers and also having extending across it a water ejecting nozzle whereby water could 4be ejected against the felt to clean it and then the water, carrying with it the foreign matter, would be drawn down into the vacuum head and discharged. The rollers illustrated in this patent were solid rollers and, as a consequence, the vacuum pulled the water out of the felt only between the rollers. When the felt, saturated with water, is held down by the vacuum inthe head against these rollers, the water cannot very well be pulled out of the felt, though it is pulled out readily as the felt travels between the rollers. 'I'he object of the present invention is to provide a construction whereby water may be pulled out of the felt at all times while it is passing over the vacuum chamber, thus making it possible to use a great deal more Water in the cleaning operation and at the same time use less vacuum, thus reducing very greatly the wear and tear on the felt.

A further object of the invention is to provide rollers over which the felt belt passes, which rollers have open spaces on their peripheries into which water from the felt may be drawn, these open spaces discharging into the vacuum head.

A still further object is to so construct thesev My invention is illustrated in the accompanying drawings wherein:

Fig. 1 is a top plan view of a vacuum head constructed in accordance with my invention.

Fig. 2 is a section on the line 2-2 o! Fig. 1, and y showing the felt passing over the vacuum head. Fig. 3 is a. section on the line 3 3 of Fig. 1. Fig. 4 is an end vie'w of one of the rolls. Fig. 5 is a section on the line 5-5 of Fig. 3. Fig. 6 is a top plan view of two adjacent rolls, these rolls being modified.

Referring to Figs. 1 to 5, I0 designates a vacuum head having practically the form shown in my previous patent, before referred to. The side walls of the vacuum head are contracted downward,'as at II, and discharge at their lower ends to any suitable conduit leading to an exhaust fan or other vacuum creating mechanism. The upper ends of the sidewalls are laterally flanged and mounted upon these side walls are vthe sections I2 which are also iianged and bolted to the side walls in the manner shown in my prior patent, these upper sections I2 being formed with inwardly extending portions or ribs I3.

Mounted within the suction head is a water injecting element I4 such as shown in my prior patent, which is formed at its upper end with relatively Wide wall portions I5, whose inner surfaces extend upward or inward defining a slot IG through which the water is ejected into or against the felt B. 'I'his water injecting element I4 is connected to any suitable source of supply under any desired pressure, there being, of course', an inlet opening to the interior of this member Il. The greater portion of the vacuum head lies to one side of the water injecting element I6 and the felt B is supported upon a pluralityv of shaking rollers after the felt has passed the water supply element I4.

The particular feature of the present invention is the construction of the rollers Il which extend across the head and which support the felt at intervals. In Figs. 3, 4 and 5, each roller, I1 is shown as hollow and provided with slots IB. These slots are preferably angular with relation to the longitudinal axis of the roller, that is, the middle of each slot is forward of the two ends of theslot. As illustrated, this roller is preferably formed with a pluralitty of longitudinally extending chambers I9 into which the slots open. The inner or bottom wall 20 of each chamber extends centrally and laterally from the middle of thef chamber so that water drawn through the slots and into the chambers I9 will gravitate down these inclined bottom portions 20 to the ends oi' the roller and be discharged downward between the ends of the roller and the corresponding side wall and into the bottom of the vacuum head and so be drawn out. It will be noted that the ribs or projecting portions I3 approximate closely to the endsof the rollers so that the felt will not be drawn down into the space between the ends of the rollers and the side walls, thus preventing wearing of the felt.

It is preferable also that the rollers be not cylindrical from end to end but that certain of the rollers be larger in the middle than'at the ends and alternate with' rollers which are larger at the ends than at the middle. The rollers which are smaller at their ends than at the middle are enlarged at the extremities, as at 2|, so as to have the same diameter at the extremities as at the middle of the roller so that these enlarged portions 2| will approximate the ribs or inward projection I8 and thus, as stated before, prevent the felt from being drawn down into the space between the side walls and the ends of the rollers.

By making certain rollers transversely convex and intermediate rollers transversely concave i (which is the `form of the rollers illustrated in my prior patent previously referred to) the endsections I2. Bearings 23 are shown for the trunnions of these rollers and a water seal 24 is used to prevent the outward passage of water'into these bearings through the side walls.

In Fig. 6, another form of roller is shown whose 'purpose is the same as the roller previously i described, that is, it is designed for the purpose of permitting the vacuum to act upon a maximum area of the fel-t. In this form, each roller 25 has the trunnions 216 at the ends and each roller is formed with a plurality of peripheral grooves 21 so that between these grooves there are the outwardlyv projecting cylindrical felt supporting portions 28. Each of these portions 28 has its periphery transversely rounded, as at 29. Certain of these rollers 25 have their first groove 21 at one end of the roller very close to thel end wall 38 of the roller. The next adjacent roller, Y. i however, is just the reverse of this, that is', this 1 relatively narrow groove 21 with its relatively thin outsidewall ,30 is disposed on the left-hand of the roller, thus the protuberant portions 28 are staggered on one roller relative to the next adjacent rollers. This causes the belt to be supported over exactly the same area as before, but

, permits a. maximum area of the belt to be ai'- fected by the vacuum particularlyinasmuch as 1 the belt will onlytouch what may be called the crests of the protuberant portions 28. By staggering these .protuberant portions 28 on adjacent rollers, the belt will be flexed i-n the manner heretofore described. The water withdraw-n from the belt will, of course, be drawn laterally over the curved surfaces 28 and down into the grooves 21 and then discharged around the central portion or shaft of the roller into the vacuum head it- Q self.

Attention 1s caued to the fact that the angular slots I8 have a particular function. With the angular slots. the faster the roll turns, the more between the ends of the rollers and the side water will be forced towards the end of the roll by centrifugal force on the same principle as a fan pump. An increase in speed of revolution of the roll would increase the tendency of the water to flow towards the deep and wide parts of the curved slots. The air ducts are so constructed that the water will not be forced back into the felt but will be guided towards the openings in the ends of the roll. In my construction the slots are in direct connection with the source of vacuumat all times and there will be no necessity of depending on gravity ow. The faster a roll turns, the more it will tend to whirl the water towards the ends of the roll. The idea and purpose of my construction both as regards that shown in Figs. 1 to 5 and that shown in Fig. 6, is to aid and assist the discharge of water by the centrifugal force of its own rotation without in any way impairing or obstructing the effects of the vacuum pump which is connected to the Vacuum head. It has also been noted that in my construction as illustrated in Figs. 1 to 5, the water will be forced into the curved pocket or chamber I9 of the duct and not into the open slot. Once the water passes into the chamber I9, the water will not get back into the felt. With the structure shown in my .prior previously referred to patent, the centrifugal action of the rolls rotating at a relatively high speed caused the Water to be thrown olf against the ielt belt and thus did not permit the full cleaning of the belt as is the case with my present construction.

With regard to the form of roller shown in Fig. 6, i't may be pointed out that the staggering of the protuberant portions, that is, the portions 2B, makes it possible to shift or alternate the area which is supported by the protuberant portions or, in other Words, certain points on the felt come in contact with one series of protuberant portions and an entirely different series of points on the felt comes in contact with the next adjacent protuberant portions. Thus not only is every portion of the belt subjected to the action of the vacuum but all and every part of the felt receives the same action from the vacuum and every portion of 'the felt receives the same flexing action. It is the rounded periphery or crests of hl protuberant portions in Fig. 6 which iiex the While I have illustrated certain details of -construction an-d arrangement of parts, it is to be understood that these may be modified in many ways without departing from the spirit of the invention as defined in the appended claim.

What is vclaimed isz' A cleaner for the felt blanket of a paper makmachine, compri-sing a, vacuum head open upon one face over which the felt passes, a series of rollers mounted in the head and extending across the open face thereof, said rollers being alternately of longitudinally concave and convex form, each of said rollers h-aving'openingsthrough its periphery into which water from the felt is drawn by the vacuum, the rollers having longitudinally extending through chambers into which the open-ings extend, the chambers discharging into the vacuum head, the side walls of the vacuum head at the top edges thereof being disposed in close proximity to the ends of the rollers and the rollers being of the same diameter attheir ends and ush with the tops of the adjacent side walls to prevent the felt from being drawn down v walls of the head.' i

LAWRENCE L. LAPEYROUSE'.

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