US2447743A - Glass-topped tennis table - Google Patents

Description

Aug. 24, 1948. I w. G. DIETER GLASS TOPPED TENNIS TABLE Filed Apfil 6, 1944 2 Sheet-Sheet l Zhwentor A TE cf DIETER 1948- w. G. DIETER' 2,447,743

GLASS TOPPED TENNIS TABLE Filed April 6, 1944 w 2 Sheets-Sheet 2 FIG. 4 FIG. 5

WALTER c. DIETER 3nvenfdr (Ittorneg Patented Aug. 24, 1948 UNITED STATES PATENT f OFFICE 2,447,743 GLASS-TOPPED TENNIS TABLE Walter G. Dieter, Toledo, Ohio, assignor to Libbey-Owens-Ford Glass Company, Toledo, Ohio, acorporation of Ohio Application April 6, 1944, Serial No. 529,708

3 Claims. (01. 311-106) The presentinvention relates to table tennis equipment and more particularly to a novel type of tennis table having a glass playing surface.

The primary object of the invention is to pro-- vide a table for the game of table tennis that will conform to all of the regulations of the United States Table Tennis Association, but which is provided with a special kind of top that is remarkably suited for this particular purpose. Specifically, I have discovered that when one side of a regular plate glass blank is ground in the usual manner but not polished, the resulting ground-glass face makes an ideal playing surface for table tennis. 7

Heretofore, most tennis tables have been made entirely of wood. In the better tables, tops-of plywood were used and up until now plywood tops have been generally considered to be the best. However, there are a number of disadvantages even with these multilayer wood tops. In the first place, the bounce of the ball from their surfaces ls not always consistent and may vary slightly on different tables or from one area to another on the same table.

Then too, it is'difiicult to obtain a surface on the top ply that is absolutely uniform and'of such complete smoothness and flatness throughout its over-all area that there will be no slight the ball while it is in play. Because of warping, checking and general wear, the average life of plywood tops in table tennis centers is only one or two years, and of course their playing surfaces are growing progressively less and less satisfactory during the entire life of the top.

Furthermore, must be painted playing field.

these wooden playing surfaces As the paint wears off, it adheres to the ball, which i objectionable, and in addition the color of the table top will vary from glaring brightness to a' dull and worn shade, depending on the length of time that it has been in use.

In contrast, the special playing surface on the tennis table of the present invention has the permanency, uniformity and flatness of a sheet of plate glass. At the ame time, it has a translucent finish that is satin smooth, without being slippery, and that appears to absorb rather than to reflect light.

From the standpoint of play, the ground glass surface is accurate, fast and responsive. It not only assures consistent and true action of the ball while in play, but it also gives an extra resilience or bounce that is not obtainable on a to provide the proper coloredv wood top, and English or spin that is put on the ball by cuts, chops or stuff, takes better on this special glass playing surface.

Other objects and advantages of the invention will become more apparent during the course of the following description, when taken in connection with the accompanying drawings.

In the drawings, wherein like numerals are employed to designate like parts throughout the same:

Fig. l is an isometric View of a tennis table made in accordance with the invention;

Fig. 2 is a plan view of one section or half of the table of Fig. 1;

Fig. 3 is an enlarged fragmentary view of one corner of the table with the glass top partially broken away to show the supporting framework;

Fig. 4 is a section taken substantially on the line 4-4 in Fig. 2; I

Fig. 5 is a view similar to Fig. 4 showing a modified edge construction for the frame; and

Fig. 615 an enlarged sectional view through the glass top showing its mechanically ground top surf-ace and its unground, ribbed and painted bottom surface. v

Referring now more particularly to the drawings, there has been illustrated in Fig. l a. tennis table constructed in accordance with the invention and which comprise a glass top or playing surface l0 that is supported on a suitable framework, designated in its entirety by the numeral H. As shown, the table is made of two identical halves or sections l2 and I3 which may, or may not, be hinged or otherwise secured together while in use. There are certain advantages in making the table in two or more separate parts in this manner. First, because it can be more easily handled and stored, and also because the individual sections can then be used independently for other purposes if desired.

However; it is to be understood that the top it, or the framework 1 l, or both, can just as well be made as single units and in speaking of the table'here, the entire assembly as shown in Fig. l is meant. 1

r The glass playing surf-ace I0 is preferably the upper surface of a glass plate or slab l4 which may be made up in one or more sections but which in any event presents a'substantially continuous playing surface of glass. The glass itself has certaininherent qualities that make it highly suitable for the purpose, such as solidity; resistance to weathering, when used out of doors; ability to take a perfectly smooth flat surface, and s'of'orth. However, the present invention goes beyond these natural advantages and contemplates the provision of a special kind of glass surface that has proved to be superior to anything heretofore used on a tennis table.

Briefly stated, this special surface corresponds in character to the surface that is formed on a glass blank at one stage of the production of regular commercial plate glass; that is, after one face of the blank has been ground but before it has been subjected to the polishing operation.

In fact, a preferred method of producing the glass tops of the invention is to mechanically grind one face of a large plate glass blank in the Joseph P. Crowley, 1,740,-

Or on a so-called continuous line as shown in the patent to Joseph P. Crowley, 1,982,641, December 4, 1941.

lucent, but it will have a perfectly smooth, fiat upper surface (as shown at I Fig. 6) with a finish that resembles delicately frosted glass; and a ribbed or corrugated lower surface f5. It is and playing surface for a tennis table.

The regulation table tennis playing surface is green in color and marked with white side, end and center lines (I6, I! and I8 respectively, Figs.

or adhere to, the ball during play.

tinder certain circumstances, it may be found piece or in sections, when supported in any suitable manner in a horizontal plane, will provide an unusually satisfactory playing surface for table tennis. However, in order to meet tournament of the table consists of a frame 20, within which the glass slab is received, and

In Fig. 3..

The strips 23; are notched as at 29 and the top of each of the legs 2i has one corner notched as at 30, to receive a brace 3|. The ends of the braces 31 are also notched as at 32 to fit into the notches 29 inthe strips 28, while the middle portion of each brace 3| is received within the notch 30 in one of the legs 21. The brace 3| is also provided with an opening 33, opposite the notch 30 in. its respective leg, for the reception of a lagscrew 34, that is adapted to be threaded into the leg.

assembled by simply putting the frame 20 in poand tightenin four order to dismantle a green cement that W111 harmonize with the color of the playing field.

In Fig. 5 there has been shown a slightly modifled type of frame 20. As there shown, the stringers 22" are not rabbeted but instead supcarried by the stringer 22' and covering both the stringer and the edge of the slab.

With the construction of Fig. 4, the stringers 22 may be made of a white material so that the marginal portions 27 provide the end and side lines for the court. On the other hand, with the form shown in Fig. 5, the end and side stripes, as well as the center stripe, will be painted on the underside of the glass slab.

It will be noted in Figs. 1 and 2 that one of the marginal portions 31 on the frame 20 is considerably wider than the other three and that when the two halves of the table are put together this is done with the two side margins adjoining one another, to provide a relatively wide band across the middle of the table to which the net clamps can be secured.

As explained above, the tennis table described here has been found to have a playing surface that is surprisingly fast, accurate and responsive as compared to the surfaces that have heretofore been considered to be best suited for the purpose. Furthermore, this mechanically ground translucent surface, marked and colored on the underside, is always uniform in appearance, the lines stand out sharply and distinctly against the field and yet there is no glare whatever. In fact, even very bright light directed onto the table seems to be absorbed and diffused by the ground glass surface without being reflected back into the eyes of the players.

There is a noticeable solidity and freedom from vibration about the playing surface and it will resist blows from the paddles during play that would nick or dent a plywood top. When the glass table tops are tempered after grinding, by first heating them to substantially the softening point of the glass and then suddenly chilling them to place the outer surfaces of the slab under compression and its interior under tension, they will be found to be practically indestructible under any ordinary treatment.

Although it is preferred to produce the glass playing surface of this invention by grinding one surface of a rough glass blank, it will be understood that a similar surface will result when a face of a transparent glass sheet is ground in the same manner. It is also appreciated that the table top might be made by a relatively thin layer of glass on a base of some other material, and that a somewhat comparable surface finish might be produced by etching, sandblasting or some similar treatment as well as by mechanical grinding.

It is to be understood that .the form of the invention herewith shown and described is to be taken as the preferred embodiment of the same, and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of the invention or the scope of the subjoined claims.

I claim:

1. A tennis table of the character described, comprising a supporting framework, a slab cut from a rough plate glass blank and carried by said framework, a smooth fiat playing surface mechanically ground but unpolished on the top of said blank, and a layer of coloring material on the bottom of the blank.

2. A tennis table of the character described, comprising a supporting framework, a glass slab carried by said framework, a flat smooth but translucent and unpolished playing surface on the top of said slab, a corrugated surface on the bottom of said slab, and a layer of coloring material applied to said corrugated surface.

3. A tennis table of the character described, comprising a supporting framework including a frame, a glass slab carried within said frame, a mechanically ground but unpolished playing surface on the top of said slab, a corrugated surface on the bottom of the slab, a white line down the middle of said corrugated surface, and a coating of coloring material completely covering the corrugated surface.

WALTER G. DIETER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 206,234 I-Iall July 23, 1878 626,554 McLean June 6, 1899 755,197 Wadsworth Mar. 22, 1904 1,135,229 Wagner Apr. 13, 1915 1,338,202 White Apr. 27, 1920 1,875,864 Gibian Sept. 6, 1932 1,950,540 Calhoun Mar. 13, 1934 1,995,543 Kaser Mar. 26, 1935 2,367,948 Kirsch Jan. 23, 1945 FOREIGN PATENTS Number Country Date 417,707 France Sept. 1, 1910

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