US1794220A - Composite paving block - Google Patents

Description

Feb. 24, 1931.

E. c. WALLACE w 1,794,220 concurs PAVING BLOCK s sheet-sheet 1 mm! Nov. 5, 1927 INVEN TOR. Sam/w C. ewazem,

rm MM Um M ATTORNEY Feh 24, 1931. E. c. WALLACE Filed Nov. 5, 1927 3 Sheets-Sheet 2 I INVENTOR. /dw/ixw 900580.68,

BY a} mam M ATTORNEY E. C. WALLACE COMPOSITE PAVING BLOCK 3 Sheets-Sheet 3 Filed Nov INVENTOR.

ATTORNEY Feb 24, 1931 Patented Feb. 24, 1931 PATENT OFFICE EDWIN C. WALLACE, OF NEWTON, MASSACHUSETTS COMPOSITE PAVING BLOCK Application filed November 5, 1927. Serial No. 231,285.

This invention relates to improvements in composite paving blocks and more particularly to blocks of this character cons sting of a substantially rigid body and a resilient surface member, designed and constructed to sustain heavy loads and to resist the thrust of the fast moving vehicles of modern trafiic.

Heavy loads moving at high speeds have developed new problems in the paving industry. Road construction which formerly was considered suitable for heavy traflic has been found to be entirely inadequate for present day tralfic conditions.

The desirable qualities of rubber and rubher compositions as surfacing material for streets and roads has long been recognized, but the very properties to which the wear resisting qualities of such material are due have retarded its adoption as a pavlng material owing to the difliculty of attaching it to a suitable base or support in such manner that it cannot be displaced by the thrust of fast moving vehicles.

It has been found that this tendency of the rubber surfacing element or mat to become displaced could be overcome by securely attaching it to a body such as a paving block, which of itself possesses considerable weight and can readily be secured in place upon a suitable supporting bed or foundation. It was also found, however, that although the general idea of such construction, in the main, was excellent, the design of the rubber or resilient mat and the method of attaching it to the block were very important factors.

It is therefore the object of the present invention to provide an improved design of block and mat and improved means for securely attaching the mat to the block whereby the difiiculties and objections heretofore encountered are effectually overcome.

With the foregoing and other objects in view, the invention consists in the novel construction and method hereinafter more particularly described and shown in the accompanying drawings, in which Fig. 1 is a top plan view of one form of the blocks showing in broken lines one design or configuration of the attaching member of the mat.

Fig. 2 is a horizontal sectional view of this block taken on the line A-A of Fig. 3.

Fi 3 is a vertical sectional view taken on the l1ne BB of Fig. 1.

Figs. 4, 5 and 6 are plan views of the form of the block shown in Fig. 1 with parts broken away and in section showin variations in the design or configuration of the attaching member of the mat.

Fig. 7 is a vertical section of a block showing a modified form of mat.

Fig. 8 is a horizontal sectional view taken on the line CC of Fig. 7

Fig. 9 is a view similar to Fig. 7 showing another modified form of mat.

In the drawings above briefly described, the preferred forms of construction have been illustrated and while these constructions will be specifically described, it is to be understood that within the scope of the invention as (plaimed, numerous variations may be ma e.

Referring to the drawings 1 denotes the body or base member of the block and 2 denotes the mat or resilient surface member of the block. The body or base of-the block may be of any desired size and shape but polygonal shapes having angles greater than 90 to facilitate casting or molding, are preferred. Hexagonal or octagonal shapes are also preferred over other forms since such blocks having all faces equal can be more easily made and more readily laid and securely held in position by surrounding blocks. The mat or resilient surface member 2 of the block is formed of a suitable rubber com position and conforms in shape to the configuration of the base or body portion 1, to which it is secured, and may vary in thickness from A; to of an inch or more, but by preference for general use is made about inch thick.

In order to firmly secure the mat'to the body of the block, the mat is provided on its inner side with one or more integral ribs or projections. In the form of the blocks illustrated in Figs. 1 to 6 of the drawing, the mats are shown as having but one centrally disposed rib 3 which is preferably made continuous and spaced inwardly from the side edges of the mat and outlines a space,

the center of which is co-incident with the center of the mat, but may be of any desired configuration which will provide lateral sup port against the thrust of trafiic regardless of the direction of the thrust. For instance, the rib or the figure outlined thereby may be hexagonal as shown in Figs. 1, 2 and 3 of the drawings, rectangular as shown in Fig. 4, circular as shown in Fig. 5 or triangular as shown in Fig. 6, since In any one of these forms every point of the perimeter is reinforced and supported laterally by the diagonal, perpendicular, or curvilinear, exten- 4 sions of the rib. These ribs are endless as shown, preferably about inch wide and from ,4; to 1 inch or more in height and are undercut on one or both sides as shown at 4 to form a recess into which the material forming the base will snugly fit.

In addition to the centrally disposed rib hereinbefore described, the mats may be provided with a peripheral rib or flange 5, as shown in Figs. 7,8, and 9. This rib or flange is preferably from to 1 inch high and undercut on its inner side as shown at 6- to form a recess to receive the material which forms the base. The peripheral flange overlaps the edge of the top of the base but the outer surface of the flan e is flush with the outer surface of the base slow the flange.

In Fig. 9 of the drawing, in addition to the peripheral flange 5, the mat is provided with a centrally disposed projection 7 having a central cup-like depression 8 and under cut outer sides as shown at 9 to form recesses to receive the material forming the base.

Since pavement blocks are subjected to the thrust of trafiic from all directions, it is essential, if they embody a resilient surface element, that that element be effectively anchored to its base. It is for this reason, therefore, that the anchoring rib of the rubber element in the present invention is inset from the bounding edges of the body portion of the element and arranged to bound a space approximately in the center of the body element. This space is thus filled with the unyielding material of the base element and the rib is reinforced throughout, onthe inside and on the outside as well, by reason of being inset from the edges. Thus a sudden blow or thrust which might result in dislocation or loosening of the rubber surfacing member, under the conventional forms of anchoring, is prevented from so doing in the present invention by reason of the rib being embraced throughout with the material of the base element. The rib being endless, it is, at the point where a blow or thrust may be'applied, always transverse to the line of such blow or thrust which also increases its resistance to dislodgment.

In producing this composite block, the mat of rubber composition which forms the surface member 2 is first formed and is then placed in the bottom of a mold of the desired size and shape, with the rib and flan bearing side u permost. The materia from which the ase or body 1 of the block is formed is then cast or pressed in the mold to snugly fit into the recesses formed b the undercut sides of the ribs and flan es. fter the block has become set or bar ened so it can be handled without,distortion, it is removed from the mold.

While it is advisable to store the blocks for some time before using, it is not necessary that this be done for any fixed period of time.

I claim A composite paving block comprising a base of hard material of the character of stone, and a surface member of resilient material of the character of rubber, the surface member having an anchoring rib embedded a substantial depth in and fully embraced by the hard material, said rib being inset from the periphery of the surface member, of endless form and bounding a. comparatively iarge space at the center of the surface mem- In testimony whereof I aflix my signature.

EDWIN C. WALLACE.

Images