US3534444A - Carding machine screen - Google Patents

Description

Oct. 20, 1970 v w. L. WALKER 3,534,444

CARDING MACHINE SCREEN Filed NOV. 29, 1968 Ivy. 4'

INVENTOR WILLIAML. WALKER ATTORNE Y5 United States Patent US. Cl. 1995 1 Claim ABSTRACT OF THE DISCLOSURE A card screen is provided which includes a curved frame. A number of elongated aligned flat transverse members are carried by the frame. Spaces are defined between adjacent edges of the flat members which are relatively narrow in relation to the flat members and legs extend outwardly from the edges away from the main cylinder substantially normal to the flat members. The total area defined by the spaces is just sufiicient to prevent blow-out at the sides of the card. The legs extend outwardly for a sufficient distance to prevent substantial recirculation of air which has been blown out through the spaces back into the space adjacent the main cylinder.

This is a continuation-impart of my copending application bearing Ser. No. 684,289, entitled Carding Machine Screen, filed Nov. 20, 1967 now abandoned.

This invention relates to an improved card screen producing an improved web by reducing the turbulence of air currents generated adjacent the main cylinder and minimizing the possibility of nep build-up.

Turbulence of the air currents generated by the high speed at which card cylinders rotate has long produced adverse affects on the web. Such affects take the form of excess waste, neps, chokes and variations in the web thickness. Many attempts have been made to ameliorate such conditions. Perforated screens have been provided with openings in fiat stock, but such do not materially reduce the formation of neps and do not substantially improve other aspects of carding. Screens constructed of triangular bars are thought to permit recirculation of air exhausted through the spaces therebetween. In any event, such have not solved the problem.

Accordingly, it is an important object of this invention to provide a card screen which will reduce variations in web thickness.

Another important object of the invention is to provide an improved card screen which will result in reduction in nep formation both from the standpoint of number and size thereof.

Another object of the invention is to provide an improved card screen for use under the main cylinder which will reduce the number of chokes on the nose of the front screen.

Another important object of the invention is the production of a clearer web of much improved quality.

Another object of the invention is the reduction of lint formation on the screen during carding and the reduction of overall waste during carding resulting in fewer damaged cylinders, dolfers and licker-ins.

A very important object of the invention is to increase the weight of the web produced while improving the quality thereof.

Another important object of the invention is the reduction of ends down on the card.

Another important object of the invention is to increase the amount of foreign matter exhausted under the card with a reduction of overall lint formation.

The construction designed to carry out the invention Patented Oct. 20, 1970 ice will be hereinafter described, together with other features thereof.

The invention will be more readily understood from a reading of the following specification and by reference to the accompanying drawing forming a part thereof, wherein an example of the invention is shown and wherein:

FIG. 1 is a schematic side elevation, with parts omitted and parts broken away, illustrating a carding machine with a screen constructed in accordance with the present invention installed thereon,

FIG. 2 is an enlarged perspective view illustrating a screen constructed in accordance with the present invention,

FIG. 3 is an enlarged sectional elevation taken on the line 3-3 in FIG. 2 further illustrating such screen construction, and

FIG. 4 is an enlarged sectional elevation taken on the line 4-4 in FIG. 2 further illustrating the screen con struction.

The drawing illustrates a screen for use beneath the main cylinder of a textile card constructed in accordance with the invention. The screen includes a longitudinal frame A curved to conform to the curvature of the main cylinder. A plurality of elongated aligned flat transverse members B are carried by the frame tangential to the curvature of the frame. The flat members B have adjacent edges defining spaces C therebetween. The spaces C are relatively narrow in relation to the width of the fiat members B. A plurality of transverse legs D extend outwardly from the edges away from the main cylinder along the edges. The legs D are substantially normal to the fiat members B and are integral therewith. The area defined by said spaces C is only slightly greater than that area at which blow-out would begin to occur at the sides of the card, and the legs D extend outwardly for a sufiicient distance to avoid appreciable recirculation of air which has been exhausted through the spaces. It will be noted by reference to FIG. 2 that relatively large imperforate portions are provided on the back screen and front screen. The imperforate portion on the back screen portion is especially extensive.

A conventional carding machine is illustrated in FIG. 1 with the frame being designated at 10. The frame carries the usual lickerin roll 11, a main cylinder 12 and a doffer cylinder 13. The frame A of the carding machine is attached by any conventional means which are partially illustrated at 14. A lickerin screen is illustrated at 15.

The frame A includes spaced curved side portions 16 and 17, each of which has two segments, as illustrated at 16a and 16b. The frame members 13 carrying the legs D are suitably attached to the frame members by interfitting (FIG. 4) and soldering (not shown). The flat members B may be slightly curved, as illustrated in FIG. 3, to conform generally to the curvature of the card cylinder or they may be planer. It will be observed that the flat members B are relatively wide and a dimension of about 3" has been found to be acceptable, although somewhat more or less may also be practical.

The spaces C are relatively narrow in relation to the width of the fiat members B and a spacing of about A has been found to be acceptable, although somewhat more or less may also be practical. It is important that the total area defined by the spaces C is only slightly greater than that area at which a blow-out would begin to occur at the sides of the card. This total area should be less than about 15% of the area of the entire screen. It has been found that 7 to 9 such spaces per screen produces acceptable results, although somewhat more or less may also be practical. In other words, the total area of such space is preferably just enough to permit sufficient air flow as to avoid substantial blow-out. The relatively large imperforate area on the back screen is illustrated at 16c, and the imperforate area on the front screen is illustrated at 1 6d. The imperforate portions extend over the major portion of said screen and limit air flow.

The legs D extend outwardly from each edge of the fiat members B in a direction substantially normal thereto. By thus restricting the total area of the spaces C appreciable recirculation of air which has been blown-out through the relatively few narrow spaces C due to limited accessibility of the screen therefor. An outward distance of to 1 has been found acceptable for the legs although somewhat more or less may also be practical. The legs D take the form of a conventional sheet metal hem wherein the metal is folded twice, as illustrated at 18 in FIG. 3. Contrary to what would have been expected, it has been found that a more uniform web is produced by carding machines equipped with a screen constructed in accordance with the invention described above. A clearer appearing web is produced while increasing the average grain weight thereof. The advantages enumerated hereinbefore are thought to occur as a result of better control on the air currents produced during carding. Less air escapes through the screen and less turbulence conditions are arrived at. No abrupt edges are presented which would encourage nep formation and a reduction of overall waste is achieved. Exhaustive field tests have proven that such results are achieved on all varieties of stock and production rates.

While a preferred embodiment of the invention has been described using specific terms, such description is for illustrative purposes only, and it is to be understood that changes and variations may be made without departing from the spirit or scope of the following claim.

What is claimed is:

1. A screen for use beneath the main cylinder of a textile card including,

(A) a longitudinal frame curved to generally conform to the curvature of the main cylinder,

(B) a relatively few elongated aligned substantially flat, relatively wide, transverse members carried by the frame substantially tangential to the curvature thereof,

(C) a substantially imperforate end portion carried by said frame adjacent each end thereof extending over the major portion of said screen,

(D) said flat members being carried intermediate said imperforate end portions,

(E) said flat members having adjacent edges defining spaces therebetween,

(F) said spaces being relatively narrow in relation to the width of said fiat members,

(G) a plurality of transverse legs extending outwardly from said flat members away from the main cylinder,

(H) said legs being integral with said flat members,

(I) said spaces defining a total area of space less than about 15% of the entire screen so that the area defined by said spaces is enough to permit suf- -ficient air flow as to avoid blow-out at the sides of the card while avoiding appreciable recirculation of air which has been exhausted through the spaces, and

(J) said legs extending outwardly from each of said edges substantially normal thereto.

References Cited UNITED STATES PATENTS Re. 8,313 7/1878 English 19-95 233,221 10/1880 English 1995 538,200 4/1895 Rascoe l995 3,348,268 10/1967 Jenkins 19-95 DORSEY NEWTON, Primary Examiner

Images