US2882801A - Machine for use in the manufacture of paper filters - Google Patents

Description

April 21, 1959 Filed July 19, 1954 E. PETTITT ETAL 2,882,801

MACHINE FOR USE IN THE MANUFACTURE OF PAPER FILTERS 2 Sheets-Sheet 1 I April 21, 1959 E. PETTlTT ET AL 2,882,801

MACHINE FOR usE IN THE MANUFACTURE OF PAPER FILTERS Filed July 19, 1954 2 Sheets-Sheet 2 United States Patent MACHINE FOR USE IN THE MANUFACTURE OF PAPER FILTERS Leslie Ernest Pettitt, Blue Bell Hill, Rochester, and Philip Rainham Peasey, Rochester, England, assignors to C.A.V. Limited, London, England Application July 19, 1954, Serial No. 444,283

1 Claim. (Cl. 93-1) This invention relates to the manufacture of a filter of a kind comprising two permeable paper strips, these being united by an adhesive along opposite longitudinal edges and spirally coiled so that the convolutions form alternate inflow and outflow passages separated by permeable partitions, the inflow passages being open to one side of the coil, and the outflow passages being open to the opposite side of the coil. Prior to combining and coiling the two strips, one of them (hereinafter referred to as the glued strip) has applied to one of its sides and adjacent to one edge a narrow longitudinal layer of adhesive, a similar layer being also applied to the opposite side and adjacent to the other edge. During a preliminary operation in which the adhesive is allowed to dry partially, a long length of this strip sufficient to make a considerable number of filters is coiled on a reel which serves to feed a machine in which the required filters are formed.

The present invention relates to the filter forming machine, and has for its object to enable the operations involved in the formation of the filters to be effected expeditiously.

A machine in accordance with the invention comprises the combination of a pair of guide rollers for the glued strip, these being mounted at a convenient distance apart in approximately the same horizontal plane, a pair of suspended and vertically movable guide rollers carried by the ends of a flexible member passing around a supporting roller situated at a position above the first mentioned guide rollers, so as to accommodate a length of strip suflicient to make at least one filter, a spindle for coiling the glued strip, a plain strip, and convolutionspacing tapes, and means for severing the paper strips.

In the accompanying drawings:

Figure 1 is a side elevation and Figure 2 a plan of a filter forming machine in accordance with the invention.

Figure 3 is a diagrammatic sectional view illustrating the mode of forming a filter by the machine shown in Figures 1 and 2, and Figure 4 is a diagrammatic cross sectional view illustrating a portion of the completed filter.

Figure 5 is a fragmentary sectional end view taken on the line 55 of, and drawn to a larger scale than, Figure 1.

Referring to the drawings, there is provided a vertical enclosure a through which the glued strip b is caused to pass to the filter forming mechanism from a feed coil prepared as described in our aforesaid co-pending application, the glued strip having two narrow longitudinal layers of adhesive (indicated by b in Figures 3 and 4) applied respectively to marginal portions at opposite sides and adjacent to opposite edges of the strip. At the entrance and exit sides of this enclosure and at about its centre are mounted a pair of guide rollers d, e, these being situated in the same or approximately the same horizontal plane. At the upper end of the enclosure is mounted a roller 1 for supporting a pair of flexible cords g, chains or the like which at their ends are attached to a pair of rollers h which can rise and fall within the enclosure, one of these rollers being weighted. At the commencement of a filter-forming operation, one of the rollers h is situated at the upper end of the enclosure, and the other at the lower end. During the filter forming operation the strip b is drawn to the coiling means at a faster rate than that at which it is fed from the feed drum, and consequently the two vertically movable rollers h are thereby caused to move towards each other until they reach the central position. The length of the strip in the enclosure is suflicient to form at least one filter.

On leaving the enclosure the glued strip b first passes under a strip-feed roller i, and thence past a knife 1 and a guide roller k to a coiling spindle m. Also on the machine is mounted a support p for a coil of plain permeable paper strip p, a feed roller 0 and a guide roller n, a second knife j being situated between the rollers o, n. The strip supplied from the coil is similar to the glued strip, but has no adhesive on it, and is required to be intercoiled with the glued strip so that the adhesive layers b serve, during the intercoiling operation, to attach the marginal portions of each convolution of the glued strip to opposite marginal portions of alternate convolutions of the plain strip. Further, there are mounted on the machine supports q for a pair of coils of spacing tapes q made from any convenient material. The tapes are fed to the coiling spindle at positions adjacent to the longitudinal edges of the glued and plain strips as shown in Figure 3, and serve to exert a localised pressure on the strips b, p at positions corresponding to the adhesive for squeezing the latter between the adjacent parts of the strips, and thereby ensuring that the marginal portions of the strips are effectively united as above described by the adhesive. The feed rollers and coiling spindle are driven by an electric motor r at suitably co-ordinated rates.

The arrangement is such that the two paper strips b, p and the spacing tapes q are simultaneously coiled on the spindle until the required length of glued strip has been fed into the machine. On completion of the coil, that is to say, when the spindle carries suflicient lengths of the two strips to form a filter, the strips are severed by the knives j, j and the action of the motor is temporarily interrupted by a clutch (not shown). While the machine is at rest, the movable rollers h in the enclosure return to their initial positions in readiness for forming the next filter. After removal of the coil from the spindle, the tapes are shaken out and re-coiled for further use. In its finished condition the filter consists of a coil of alternate glued and plain strips united together at opposite edges as represented by the fragmentary view in Figure 4.

In the machine forming the subject of our concurrent application for patent above mentioned, two feed strips are formed successively in a manner which obviates intermission of feed to the filter making machine, the feed coils occupying adjacent positions. After the whole of one feed coil has been utilised on the filter making machine, the coiling mechanism of this machine is moved laterally to bring it into line with the next available feed coil, the said mechanism being mounted on a slide s which is movable on a fixed guide t on the bed of the machine.

The knives j, j are similar to each other, and may have any convenient form. Thus, each of these knives may have the form of a pivoted and spring-loaded blade as exemplified in Figure 5 in which the knife 1' is shown pivoted on a horizontal axis at u and loaded by a spring w, this knife being movable by hand about its pivot axis against the action of its loading spring.

Having thus described our invention what we claim as new and desire to secure by Letters Patent is:

A machine for making filters of the kind comprising two juxtaposed permeable paper strips spirally wound in the form of a coil having its convolutions united along alternate longitudinal edges by adhesive initially applied to a longitudinal marginal portion of one of the strips and to the opposite longitudinal marginal portion of the other side of the last mentioned strip, the machine comprising in combination a first pair of spaced guide rollers around which the adhesive-carrying strip can pass, and which are supported on fixed axes in the region of the same horizontal plane, a second pair of vertically movable guide rollers around which the adhesive-carrying strip can pass after leaving one, and before passing around the second, of the first pair of guide rollers, and which are suspended respectively above and below the said region, a supporting roller mounted on a fixed axis at a position above the uppermost of the second pair of guide rollers, an elongated flexible suspender passing around the supporting roller and carrying the second pair of guide rollers so that the latter can assume positions in which the length of the adhesive-carrying strip required to pass around both pairs of guide rollers is sufiicient for at least one filter, and thereby enable the strip to be withdrawn from the said second roller of the first pair at a faster rate than that at which it is fed to the other guide roller of the first pair, a support for a coil of adhesive-free permeable paper strip, a pair of sup- 5 4 ports for coils of spacing tapes, a spindle which is arranged at a position between the said pair of supports, and also between the other support and the said second roller of the first pair, to receive the adhesive-carrying strip after it leaves the said second guide roller of the first pair, and to Withdraw the adhesive-free paper strip and spacing tapes from the corresponding supports, and on which the paper strips and spacing tapes can be-intercoiled with the tapes between the adjacent adhesivefree longitudinal marginal portions of the strips, and means for severing the paper strips after predetermined lengths thereof have been intercoiled on the spindle, and preparatory to the removal of the spacing tapes from the intercoiled lengths of the paper strips.

References Cited in the file of this patent UNITED STATES PATENTS 1,942,654 Ladd Jan. 9, 1934 1,993,728 Aivaz Mar. 12, 1935 2,064,239 Aivaz Dec. 15, 1936 2,202,839 Davidson June 4, 1940 2,221,443 Davidson Nov. 12, 1940 2,242,751 McFarland May 20, 1941 2,359,475 Gauthier Oct. 3, 1944 2,561,165 Arcement July 17, 1951 FOREIGN PATENTS 629,641 Germany May 13, 1936

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