US2414098A - Soap - Google Patents

Description

Jan. 14, 1947.v

-J. GARVEY ETAL4 Original Filed June 1, 1944 Patented Jan. 14, 1947 SOAP dames Garvey, Arthur Garvey, and Horace Maselne Garvey', Vancouver', British Colum-- bia, Ganada @rig-,finalA application` June 1, 1944, Serial No'. 538,296. Dividedand this. application June 6,` 1945, Serial-N0. 597,820

(C1. e-railI This invention relates to milled soapthat is, soap which, after being initially solidified; is partially dried and milled and then compressed into barV form by means of a plodder. Such soap is known in the trade as toilet so-ap.

At present, toilet soap is produced in the form of a bar having a longitudinally extending grain. Soap cakes are cut from the bar transversely to its length, the ends of the cake being the-faces cut from the bar. The result is that in each cake the grain runs from end to end parallelto the upper and lower faces and to the sides.

It has been considered important in the art that the grain in soap cakes should run from end to end as described rather than from face to face. After the cakes have been cut they areV usually subjectedto a pressing operation to give them a `finish and to impress a desired design or' trade mark on the faces. The finish obtainedon pressing a face which is parallel tothe run of the grain is more satisfactory than one obtained on pressing a face which is transverse to the runV of the grain. Moreover, a face of the first type will dissolve more slowly and evenly and will remain smoother during normal use than one of the se'cond'type, and the reduction of the soap to jelly, which takes place when a cake stands in a soap dish with water, is, much less rapid if the immers-ed face is of the `first than if it is of the second type. Since, in use, the principal action of water and rubbing takes place on the faces and sides rather thanon the ends of a soap cake, it follows that the grain in the cake should run from end to end rather than in either of the other two possible directions.

Conventional soap cakes have a number of defects which result from'the grain formation referred to. The Imost `serious of these is what is known as wet cracking. This occurs during the wash-down life of the soap, principally as a result of the soap drying between periods of use. Cracks, running lengthwise of the grain, often appear in the faces andv sides of the soap cake in these circumstances and become more marked the more closely the cake approaches the end of its wash-down life. Dirt-settles in these cracks during subsequent use of the soap and causes dirty marks which run lengthwise of the faces and are difficult or impossible to remove, as almost any user of soap has observed. Moreover, as the soap approaches approximately the last quarter of its wash-down life, these cracks often become so large as to cause the cake to split up into small pieces, which are substantially unusable and have to be thrown away, although, if

the cake had not broken up, it' wouldstil'l be large enough to be' useful. Another difliculty with conventionalsoap cakes' arises from what is known as checking i. e., the formation of surface cracks in. the soap cakes' during storage, before use. This is believed to result largely from occasional unavoidable failure to maintain proper ingredient' control, moisture content and temperature conditions during the manufacture of the soap; if the proper conditions are departed from', the resultingcakes may tend t'o check in storage. Considerable quantities of soap which has this defect are returned by dealers to manufacturers and' are generally thereafter usable by the latter only in the manufacture of a relatively low grade product;

An additional disadvantageof the conventional longitudinal grain is that, if the cross sectional shape ofthe cake isto be other than rectangular, e. g., octagonal, there must be an additional cutting operation before the final pressing, In the case of an octagona'l cake thisoperation consists of cutting off four corners. Not only does this additional cutting operation involve extra manufacturing expense but it involves' waste, in that the piecescut oflEj the corners are of inferior quality whenreprocessed and are consequently not used by' most manufacturers in their high grade soaps. Thecutting operation, of course, also increases the area of the cut faces on the cake.

According to the present invention a soap cake has a helical grain, which preferably runs from face to face, as contrasted to a grain which runsV longitudinally from end to end in conventional soap cakes. Such a helicalvgrain' avoids many of the objections resulting from the conventional longitudinal graindiscussed above. A soap cake with a helical grain has far less tendency towards wet cracking and checking than a conventional cake. It can be shaped to anyde sired cross section during formation ofthe bar without a separate cutting operation, andwill retain this shape during its `wash-down life better than a' conventional barshaped by suoli a separate cuttingope'ration.

Soap cakes according to the inventionlmay be made in ordinary apparatus with only very slight alterations. These consist principally in removing the usual perforated pressure plate which is mounted in the plodder casing at the discharge end of the feed screw to extend transversely of the axis of the latter and replacing it by a pressure plate mounted between two adjacent flights of the feed screw near its discharge end and. extending longitudinally of its axis.

3 The invention will be described in more detail by reference to the attached drawing in which;

Figure 1 is a longitudinal section of an apparatus for producing soap cakes according to the invention,

Figure 2 is a section along the line 2-2 of Figure 1,

Figure 3 is a section on the line 3 3 of Figure 1,

Figure 4 is a view illustrating a coiled strip of soap during the initial stages of compression,

Figures 5 and 6 are views showing 4the grain formation in bars of soap of different cross section, and

Figure 7 is a view of a completed cake of soap illustrating the grain formation.

Figure 1 shows a plodder A havingthe usual cylindrical casing I, filling hopper 2 and feed screw 3. Attached .to the cylindrical casing I beyond the left hand or discharge end of the feed screw 3 is the plodder nozzle 8 having a substantially cylindrical portion 9 and a conical portion I0. At the outer end of the latter portion is an opening II in which may be mounted a die or forming plate I2. Attached to the nozzle 8 may be a suitable conventional mechanism for cutting a bar of soap into cakes.

Mounted between the last two ghts 29 and 30 of the feed screw 3 is a perforated plate 3| provided with a large number of small openings 34. As shown in Figures 2 and 3, it extends from the shaft 32 to the Iperiphery of the feed screw and is let into slots in the shaft 32 (Fig. 2) and the adjacent ights 29 and 38 (Fig. 3). There may, if desired, be arranged on the leading side of the plate 3| a strainer screen 33 for removal of any impurities present in the soap.

It will be appreciated that rotation of the feed screw 3 in the direction shown by the arrows in Figs. 1 and 2 will force soap fed by the feed screw to pass through the openings 34 in the plate 3l. The soap emerges from these openings in the form of strips 48 (Fig. 4) having a longitudinally extending grain, which, upon continued rotation of the plate 3l, are left .coiled helically about an axis substantially coinciding with the axis of rotation of the feed screw. As operation of the feed screw continues, the plodder nozzle 8 becomes filled with soap strips coiled about an axis which extends out through the opening II. Continued movement of these coiled strips towards the opening, which is caused by continued operation of the feed screw, causes the coiled strips to be compressed both longitudinally and transversely of their axis by the conical portion I of the plodder nozzle until they are extruded from the opening II and die I2 in the form of a bar. This bar is cut at appropriate intervals transversely to its axis by any desired form of cutting mechanism.

Figure 4 shows a portion of the coiled mass of soap as it would be found in the nozzle 8 of the plodder looking from the point at which the strips 40 of soap are rst extruded from the openings 34 of the plate 3I. Owing to the separation of these openings the strips will at first be separate and distinct from one another but, as they are 4 forced along the plodder nozzle, they will merge to a greater and greater extent. This is more or less diagrammatically illustrated in Figure 4 by showing the individual strips as entirely separate at first and then in contact, with their boundaries defined by lines 40a which are first continuous and then become more and more broken. This figure also illustrates diagrammatically the longitudinal compression of the coils which takes place as they advance through the plodder nozzle, the lines 4I indicating .the boundaries between successive coils of the group of strips extruded from the plate, becoming, as can be seen, closer and closer together as the end of the nozzle is approached. These lines are, for purposes of clarity, shown as unbroken throughout, although there is of course a merging between adjacent strips of different coils just as there is between adjacent strips of the same coil.

Figs. 5 and 6 show sections of -bars of soap formed by dies of different shapes. In these bars the individual strips or groups of strips cannot be detected by ordinary observation or as a result of ordinary use. However, dotted lines are used in these figures to show .the general run of the grain. It will be noted that the grain runs generally in the form of coaxial helices of increasing diameter from the axis to the surface of the bar, the cross sectional contour of these helices following generally the contour of `the die from which the bar was extruded.

Fig. 7 shows a cake cut from the bar illustrated in Fig. 5. It will be noted that the cake is cut with its faces 42 transverse to the axis of the bar, its sides 43 and ends 44 being the sides of the bar. Since the pitch of the helices referred to above can be made quite low, as indicated by dotted lines on the sides 43 and ends 44, it follows Athat not only the sides and ends but also the faces of the cake run substantially parallel to the grain.

The essence of the invention is that the soap cake should have a helical grain. Preferably the grain runs helically from face to face of the cake, that is as illustrated in Figure 7. This is the grain which results from cutting the cake from a bar such as illustrated in Figure 5. One advantage of the grain running helically from face to face is that the cake may be shaped upon extrusion from the plodders rather than by a separate operation as is required by the present claims. However, the strength and. coherence of the cake is not affected by the direction in which the helical grain runs. From the point of view of strength and coherence the grain might run helically from end to end or from side to side.

This application is a division of our prior ap `plication Serial No. 538,296, filed June 1, 1944.

What we claim as our invention is:

1. A cake of soap having a helical grain substantially throughout the cake.

2. A cake of soap having a grain which runs helically from face to face of the cake.

JAMES GARVEY. ARTHUR GARVEY. HORACE MASELINE GARVEY.

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