US1688902A - Building brick - Google Patents

Description

Oct. 23, 1928.

1,688,902 H. R. STRAIGHT BUILDING BRICK Filed March 8, 1926 iii Patented Get. 23, 1928.

UNITED STATES PATENT OFFICE.

HALVEB R. STRAIGHT, OF ADEL, IOWA.

BUILDING BRICK.

Application filed March 8 19.26.

The object of my invention is to provide a building brick or the ..ike so constructed that the drying and burning and cooling of the brick in its process of manufacture may be more rapidly accomplished without setting up excessive shrinkage strains, and at the same time provides means whereby the shearing strength between the brick and the mortar joints, when they are supported in a wall construction, will be greatly increased, and the tendency of the brick to float in green mortar, while being laid, is decreased.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects cntemplated are attained, as hereinafter more fully set forth, pointed out in my claims, and illustrated in the accompanying drawings, in which:

Figure 1 is a plan view of my improved brick.

Figure 2 is a side elevation of same, a portion of which is shown in section.

Figure 3 is an end elevation of same, a portion of which is in section.

Figure fi: is a diagrammatical view illustrating the manner in which the drying takes place with my improved construction.

Figure 5 is a diagrammatical view showing the manner in which the drying takes place in the ordinary construction.

Figure 6 is a segmental plan view of modilied form of my improved brick.

I have found that if an undried brick of rectangular cross section is placed in a drier and subjected to rapid drying, the brick will dry more rapidly near the outer surfaces than at its center, and set up shrinkage strains to such an extent that warping or cracking will take place.

I have also found that when the brick is thus rapidly dried, the moist area or undried center gradually assumes the shape of .an ellipse, as viewed in cross'section, in somewhat the manner as illustrated by the line 10 in Figure 5 of the drawing.

I have. also found that the drying takes place quite rapidly until it has dried to such an extent that this elliptical formation is quite pronounced, after which the rapidity of the drying process decreases until the center has dried thoroughly. It often happens that on account of the length of time required to dry the center of the brick, they are placed in the burning kiln before the center is completely dried, or while the center contains a Serial No. 93,241.

higher percentage of moisture than the outer surface, while asa matter of fact to obtain the best results in burning, the bricks should be uniformly dried before being placed in the burning kiln. If the bricks are placed in the burning kiln before the centers and outer surfaces are of a uniform dryness, vapors and gases will be formed within the bricks, causing pressure strains as well as shrinkage strains, which further assist in warping and cracking and internally straining the brick, and produces a product of very inferior quality and strength.

Referring to Figure 5, let it be assumed that the drying has progressed to the elliptical line 10. It will then be seen that the distance from A to B is greater than the distance from O to D, and the distance from C to D is greater than the distance from E to F, and that the outer drier surface is very ununiform in thickness, so that a number of weak points are established where cracks or fractures or strains may easily take place. It will further be seen that if the top and bottom surfaces 11 and 12 of said brick were increased, the elliptical line 10 might be made to assume an elongated loop with its sides substantially parallel, as indicated by the numeral 13 in Figure 4.

To accomplish this result, 1 have formed in each of the outer side surfaces of the brick 14- a series of transversely and longitudinally extending V-shaped recesses 15, so that the said surfaces are provided with a series of outwardly extending pyramids 16, thus increasing the exposed drying surface of the central portion of the side faces of the brick. The rapidity with which the brick dries is in proportion to the surface exposed to the drying medium.

It will further be seen that the grooves 15 are deeper at their central portions than at their ends, so that the surfaces of the pyramids at their centers are considerably greater than the surfaces of the pyramids at the edges and ends of the brick. The depth of these grooves can be so calculated that the drying line 10 shown in Figure 5 will assume a flatter condition, as illustrated by the line 13 in Figure 4, thereby providing means whereby the sectional area of the drier portion of the brick is of substantially uniform thickness 011 all sides, and thereby eliminating to a large extent the possibility of weak points in said drier portion, where cracking and. warp ing and straining would take place;

To further illustrate this method of drying, let it be assumed that the distance from C to D in Figure 5 is equal to the distance from G to H in Figure 4. It will readily be seen that the time for drying the brick, as illustrated in Figure 5 from the point I) to C, would be the same as required to dry the brick illustrated in Figure 4 from the point H to the point G. It will further be seen that the brick, as illustrated in Figure 4, is practically dried while the brick in Figure 5 is only about two-thirds dried.

In Figures 1, 2 and 3 I have shown the central portions of the sides of the brick formed with a series of pyramids which are deeper at the central portion of the brick. It will be seen that the same result might be accomplished by simply making either longitudinal or transverse grooves, somewhat as shown in Figure 6. I preferably leave a narrow band or border 17 around the outer edges of the side surfaces which has not been grooved, to form a protection for the pyramids 16, as well as to give the brick the appearance of being of rectangular formation, as viewed from the ends or edges.

It will further be seen that by providing the upperand lower surfaces of the brick with the pyramids 16, I have provided means whereby the shearing bond between the brick and the mortar joint will be greatly increased when the brick is laid in a. wall construction. This is also a very desirable point, due to the fact that a mortar joint is the weakest point in the wall construction, especially in hard and vitrified brick, and bricks of this kind laid in mortar will make a wall of greater lateral strength than when not indented on the surfaces.

The diagrams in Figures 4 and 5 show the approximate condition that would take place if the plastic brick were subjected to a drying medium where all of its surfaces were entirely exposed thereto. It happens, however, in actual practice that the bricks are usually stacked on edge, while in the drying kiln, which considerably reduces the drying effect of the edges of the brick and would alter the shape of the elliptical line 10, cansing it to be somewhat flatter than illustrated in Figure 5, in which case the depth of the central portions of the. grooves 15 would have to be somewhat decreased. In fact, it will be seen that in actual practice other portions of the surface of the brick other than the center might have to be provided with deeper grooves. The location of these deeper portions of the grooves would have to be arranged to meet the working conditions of the particular kiln and the manner in which they are set for the different processes in which the bricks are being dried, burned and cooled.

It is well known fact that bricks are more or less under a. continuous strain, due

to expansion and contraction as they pass which the carbonaceous fuels burn out of the brick and at the time vitrification takes place, shrinkage and contraction again takes place. As the bricks are rapidly cooled, it will be seen that the outer surface again contracts in about the same manner as described for drying.

Thus it will be seen that I have provided a brick so constructed that the contraction and expansion may be taken care of in such a manner that the time for drying, burning and cooling may be materially shortened without setting up disastrous internal and external strains.

I claim as my invention:

1. A brick of substantially rectangular formation, two of the opposite faces of said brick being provided with a series of intersecting grooves to form outwardly projecting members,'the grooves being deeper at their central portions than at their ends, and so proportioned that the drying surface of said opposite faces will be gradually in creased from their edges to their central por' tions. 7

2. A brick of substantially rectangular formation, two of the opposite faces of said brick being provided with grooves deeper at their central portions than their outer .ends, so that the drying surface of said faces will gradually increase from their edges toward their central portions,

HAL'VER R. STRAIGHT.

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