Feeding and distributing mechanism

June 8, 1943. n. p. harshberger 2,321,082

FEEDING AND DISTRIBUTING MECHANISM

Filed April 29, 1939

<img file="US2321082A_D0001.tif" />

<img file="US2321082A_D0002.tif" />

Patented June 8, 1943 2,321,082

UNITED STATES PATENT OFFICE

2,321,082

FEEDING AND DISTRIBUTING MECHANISM

Norman P. Harshberger, Scarsdale, N. Y., assignor, by mesne assignments, to Carbide and Carbon Chemicals Corporation, New York; N. Y., a corporation of New York

Application April 29, 1939, Serial No. 270,731

Claims. (Cl. 91—43)

Tills invention relates to feeding and distributing apparatus for coating compositions and to methods utilizing such mechanisms. The present invention is a continuation-in-part of my copending application Serial No. 26,770, filed 5 June 15, 1935, now Patent No. 2,156,286.

The feed and distribution of composition materials, for instance, plastic or sludgy coating compositions, particularly where the composition is removed from a hopper by a roll having a 10 formed surface and is then removed from the roll by a rotary impeller, presents various problems with respect to the feed roll, the impeller, and the removal of the composition from the source of supply. For instance, it has been found that dis- 15 tributing impellers of the bristle type commercially available do not stand up. These impellers are made by the ordinary brush making processes whereby small groups of wires are bent at the center and anchored as a group in holes of a core 20 piece by a wire or other frictional holding means. Also, sometimes a number of groups are arranged around and between fiber discs and held by wire bands. These form segment brushes and a number are ganged together to make an impeller. 25 The individual bristles of these conventional brushes shift from their anchorage under the stress and strain to which they are subjected in impelling operations, become loose, and either extend beyond the limits of the normal impeller 30 periphery or else lose anchorage completely. Moreover, brushes of this type do not have their wire bristles uniformly distributed or uniformly anchored, and have their bristles extending in all directions. These conditions have a tendency to 35 affect adversely uniform distribution of coating materials, and, where thin coating applications are to be made, contribute to streaky results. It has also been found that the character of the feed roll surface profoundly affects the life of the impeller and is particularly important when feeding compositions including fiber.

It is the broad purpose of this invention to provide a feed roll of a character that will give efficient service, will wear well, and will be par- ⁴·* ticularly applicable to the feed of plastic or sludgy compositions, for instance, hydraulic cement. It is also the aim of this invention to provide a rotary distributing member of the bristle type, in which the bristles are uniformly ^ύspaced and securely anchored, and which may be uniformly stressed in operation.

Another object of the invention is to provide a cylindrical feed roll, the surface of which is provided with a plurality of pin or tooth-like projec- ·^Γ>,>tions substantially uniformly arranged over the surface and in a manner such that the projections around the periphery do not block each other.

A further object of the invention is. to provide a ^fi0 feed roll having surface projections to positively feed coating compositions, and which is particularly adapted to feed fibrous compositions.

Another object of the invention is to provide a feed roll having pin-like projections with rounded ends uniformly spaced in rows over the surface of the roll, with adjacent rows in staggered relation and uniformly spaced from each other.

Another object of the invention is to provide a feed roll having a plurality of tooth-like projections, the forward faces of the teeth of which are substantially radial and the rear sides of the teeth form an acute angle with the roll surface, whereby to reduce fatigue of a bristle distributor in operation.

Another object of the invention is to provide a' feed roll having longitudinally extending rows of spaced apart thin tooth-like projections, the projections being sufficiently thin to pass between bristles of an engaging impeller without inducing substantial lateral stressing and bending of the bristles.

Still another object of the invention is to provide a feed or distributing member comprising a flexible base sheet and a plurality of rows of spaced apart Li shaped metallic pieces assembled thereto with their side arms or prongs projecting through the base sheet and extending normally from the front face of the sheet, the base oUthe U pieces abutting the rear face of the sheet/

A further object is to provide a rotary distributor roll having a plurality of spaced flexible pin-like elements projecting normal to the roll surface, each element being spaced from the next element and a pair of elements being connected at their base.

Another object is to provide feed and distributing mechanism for plastic or sludgy compositions comprising a hopper, a feed roll having facial projections uniformly arranged over its surface and the outer ends of e|Mi of which are spaced from adjacent projections, and a distributing element to operate in contact with the feed roll and comprising a base material having secured thereto a plurality of U shaped elements, the sides of which produce flexible bristles.

These and other objects of the invention will in part be understood and in part be more specifically pointed out in the following description when taken with the claims and taken in conjunction with the accompanying drawing, wherein

Fig. 1 is a sectional elevation of a typical coating unit embodying emphasized features of the invention.

Fig. 2 is a plan view of part of the feed roll of Fig. 1.

Fig. 3 is a partially developed view of a feed roll of modified form.

2,3

Fig. 4 is an enlarged sectional view taken at 4—4 of Fig. 3.

Fig. 5 is a sectional view of a roll adapted for use as a feed element or distributor.

Fig. 6 is an end view of Fig. 5, and

Fig. 7 is an enlarged detail showing the construction of the surface portion of the member of Fig. 5.

Referring to the drawing, Fig. 1 illustrates a typical coating unit disclosed in my copending application aforesaid and which comprises a hopper 10, a rotary feed roll 12, a rotary impeller distributor 14, and a moving base web or conveyor 14, which receives the composition fed from the hopper 10 by the feed member 12 and impelled against its surface by the distributor 14. The side wall 11 of the hopper may be adjustable so as to act as a gate for the roll 12. Any other character of gate such as a rotary rubber roll may be used.

A feature of the invention is the structure of the feed roll shown in Fig. 1. The roll is a cylindrical member provided with individual projecting elements such as pins 18, which may be variously spaced over the surface thereof and 2 are adapted to positively engage and pull the composition in the cooperating hopper 10 so as to feed the same to the distributing member &lt;4, preferably an impeller. The pins or projections preferably are of circular section and may be driven into suitable receiving sockets or holes in the face of the roll. Preferably, the pins extend a uniform distance from the roll surface. The ends of the pins are preferably rounded so as to reduce the wear of the distributor bristles when operating in contact with this member; also, to reduce side stressing and bending of the bristles. This character of feed roll is particularly efficient where the composition is so adherent as not to feed readily from the hopper and where the composition is coarse or fibrous. With coatings of such character, it is generally essential that the distributor member operate in the material carrying spaces down between the projections of the feed member, and the character of construction disclosed in Figs. 1 and 2 is very efficient for this purpose. It will be noted in Fig. 2 that the pin-like projections are spaced apart uniformly⁷and are arranged in uniformly spaced rows extending longitudinally of the roll; also, that the pins of adjacent rows are in staggered relation. It will, of course, be understood that the pins need not be staggered. However, it is desirable that the adjacent teeth around the periphery not block each other. Obviously, the pin projections will be of a size and shape dependent upon the particular composition to be fed. Their spacing will also depend upon the composition, and additionally upon their size. The projections may also be in the form of bars or blades, or may constitute prongs or bristles.

In Fig. 3,1 have shown a feed roll 20 of slightly modified form that I have found to be particularly efficient in commercial operations, especially for positively feeding long fibrous material, particularly when such is part of a wet composition such as a hydraulic cement and the like. It will be noted that the roll is made up of uniformly spaced longitudinally extending rows of tooth-like projections 22, with adjacent teeth in 7 the rows Uniformly spaced from each other. The surface of the roll appears, in effect, to be made up of a plurality of spaced apart circular slotcutters. It will be noted that the faces 24 of the teeth (Fig. 4) are substantially normal to the 7

1,082 roll surface. These faces constitute the forward moving faces of this member and provide a positive feed. The rear faces 26 of the teeth are cut back to provide clearance between adjacent teeth i circumferentially and to obtain coating carrying spaces. Preferably, these faces form an acute angle with the roll surface so that a wiping action is obtained by the impeller filaments or bristles in riding over them. In this manner, the fed 0 material is readily removed and fatigue of the impeller bristles in operation is reduced to a miniipum. Also, shearing of the bristles is substantially prevented. The teeth are also made substantially thin to permit the bristles or ma5 terial carrying filaments of the distributor, when operating enmeshed with the feed roll and at a high speed, to receive only a slight lateral bending stress. However, the teeth are provided with a broad base circumferentially. As a typical ex0 ample of a practical construction of such a roll,

I have found that for feeding cement compositions a roll having teeth of a % circumferential pitch, that are A high, %₄ thick, have A tips, and that are spaced apart Ά along the 5 longitudinal axis of the roll, is particularly efficient. It will be noted that the adjacent teeth longitudinally are in line and form sharp cornered block-like projections and depressions; moreover, that the adjacent teeth circumferen^ 0 tially do not block each other. The arrows in Fig. 4 indicate the relative directions of motion for the face of this member and an engaging impeller.

A particular feature of the invention is to pro15 vide a material distributing impeller or feed member having a surface comprising spring-like filaments that may be uniformly stressed in operation and not readily deformed, and that may be uniformly spaced and positioned. Such a mem0 ber is shown in Fig. 5 and may take the form of a roll 28, comprising a tubular shell 30 mounted on end hubs 32 and over the surface of which is arranged a plurality of uniformly spaced projections, such as flexible filaments or bristles 34, 5 each of which projects substantially radially from the roll center and is normal to a longitudinal section through the roll. As will be seen in Fig. 7, the filaments 34 may comprise the projections of U pieces 36, which are assembled in a layer 0 or mat 38. The U pieces may be of a suitable tough and high strength metal wire, preferably of non-rusting properties and highly resistant to abrasion. Round wire is preferred, although wire of other sections may be used. The layer 38 may 5 comprise, for example, a laminated structure of alternate layers of rubber 40 and canvas 42, making, in difect, a reinforced rubber layer similar to rubber belting. The U pieces 36 are positioned so that the base 44 of the U is firmly set against 0 the under rubber or fabric face 46 of the layer 38, and such that filaments 34 freely project from the opposite side 40, preferably rubber. The effect of the U shaping of the elements 36 is to prevent the filaments 34 from shifting in their 5 mounting, the sharp bends at the base of the

U preventing any such action. In the ordinary bristle brushes, no such anchorage is provided, for the wire bristles are mounted in groups or tufts, the wires being bent at the center and se0 cured in recesses of the core by an anchoring wire in the form of a loop that is slipped over the group and pulled down. In operation, the individual strands of the tufts work from under the loop and come out or extend beyond the nor5 mal outside face of the brush. The effect of the

2,321,082 resilient base layer 38 in Fig. 7 is not only to hold the U pieces securely in position, but also to permit the filaments 34 to obtain a slight rocking action in operation. This reduces the stress on the filaments, and also wear. It will be observed that bases 44 of the U members 36 lie parallel to the roll axis in Fig. 5, or stated otherwise, they lay normal to the direction of movement of the member 28.

It will also at once be apparent that the construction disclosed in Figs. 5 to 7 permits the filaments to be uniformly and accurately spaced, and that each individual filament will carry the composition to be handled, whether this member be used as a distributor or feeder. With the conventional type of distributor, there is a whole group of bristles that operate as a single projection, so that their action is stiff, uncertain, and inefficient. When the form of invention in Figs. 5 to 7 is to be used as a distributor, particularly as an impeller, the filaments 34 will preferably be resilient and of substantial length so that a considerable wiping action is obtained when these filaments engage a surface of the feed roll, for instance, those in the drawing, and/or the coatings carried thereby. It will be understood that a similar construction may be utilized for a feed roll, but in this case it is generally preferred that the filaments 34 be fairly rigid and stubby. It will be understood that for feed roll operations, the pieces 36, instead of being of uniform cross section, that is, round or square and wire-like, may be thin sheet metal stampings, in which the projecting elements will preferably have a shape like that disclosed for the teeth of Fig. 4. While it is preferred that the pieces 36 be mounted in a rubber or other water resistant base that will protect the base of these pieces and also resist adherence of the coating, in certain cases, for instances, in the case of feed members, this layer may be of perforated flexible metal.

The roll 28 may be surfaced with a conforming sheet of the base material 38 carrying the filaments 34 the full length of the roll, or may be made up of narrow, spaced apart sections. Moreover, the roll covering may be of sections formed into rings with adjacent rings stitched together and slipped over the roll. It will, of course, be understood that the material will be suitably anchored to the shell 30, for instance, by a suitable cement, preferably a water-resistant, resinous one. I have found a satisfactory construction for an impeller distributor for cement to be a covering of a rubberized fabric carding material several inches in width, having U shaped pins made of .011 stainless steel wire projecting 1” from the face of the base material. The distance between the filaments was about ’A'' and the thickness of the base rubberized fabric was about A. The material was formed into rings and cemented to the roll core with adjacent rings stitched together.

It will be understood that the member in Figs. 5 to 7 may replace the ordinary bristle brush i4 of Fig. 1, and where proper lengths of filaments are employed, may serve also as either the feed roll 12 or both feed roll 12 and distributor i4.

From the foregoing description, it will be seen that I have provided particularly novel feed and distributor mechanism for feeding various coating materials, particularly sludgy or plastic compositions like hydraulic cement. It will be fully apparent that the constructions of Figs. 5 to 7 may be utilized as a rotary member of belt-like character, although such is not preferred. It will also be apparent that various, modifications 5 will suggest themselves to those skilled in the art without departing from the spirit and scope of my invention, which is to be construed as broadly as the following claims taken in conjunction with the art may allow.