Ernst eduard martienssen
US 1665104 A
Description (OCR text may contain errors)
April 3, 192s.
E. E. MARTIENSSEN DRAINAGE SYSTEM FOR PLAYING GROUNDS Filed April 12. 1927 10 y 7 dg o .g5 D
1 gg. @55% ,iQDmoQ E11/wif.- /yd/'ysfen M KW Patented Apr. 3, 1928i UNITED STATES l team PATENT orifice.v
ERNST EDUARD MARTENSSEN, OF HAMBURG, .GERMANY.
DRAINAGE SYSTEM FOR PLAYING GROUNIDS.
Application tiled April 12, 1927, Serial No. 183,220, and in Germany December 29, 1925.
This invention relates to a system conditioning the surface of playing grounds,
tennis courts and the like having a drainage or foundation layer. Y
Tennis courts as heretofore constructe suffer from the drawback that the upper layer dries up very quickly and is then too dusty. A consequent additional drawback is rapid wear of the surface, so that frequent repairs of the upper layer are necessary, involving considerable expense. To prevent the formation or the rising of dust, it was common practice to moisten the ground by sprinkling, but even this involves labour and cost.
These drawbacks result from the endeavour to lead away the rain water as quickly as possible, so as to keep the upper layer or surface free from water. The leading oif of the rain water is either effected by inclining the court and conducting the water from the upper surface into a drain, or by giving the water an opportunity to infiltrate to a greater depth; also both expedients have been adopted concomitantly. It is true that even after heavy rain quick drying up of the ground has been insured, but the drying is found to be so rapid and complete that formation of dust on the upper layer is an inevitable consequence.
The object of the present invention is to secure a permanently correct condition of playing grounds or courts and above all to prevent full drying up of the covering or surface layer, which is liable to cause the development of dust.
wWith this object, according to the invention, the intermediate carrying or foundation layer between the covering layer and the natural or artificial impermeable layer is so constructed or so conditioned that it is adapted to take up a certain amount of water and to hold it for a considerable time. This draining foundation layer, owing to its contents of water, automatically gives up moisture to the covering layer at such a rate that the latter cannot dry up to such an extent as to occasion the development of loose dust.
In order to promote the transmission of moisture to the covering layer and'in order to regulate the amount of moisture Within the layer in case continued drought or frequent heavy rains should influence the condition of the playing ground there is provided a sluice valve or other regulator for controlling the water running off the carryV ing layer. This valve serves as a means of controlling the moistness of the playing lduring dry weather, while the playing ground can be kept in such a condition that it may be used in continued wet weather by fully opening the valve.
Tn the accompanying drawing Figs. l and 2 illustrate two embodiments of the invention.
In both constructions shown the playing ground consists of the covering layer a made of anymaterial known heretofore in usual manner, the impermeable layer Z) and the foundation layer c disposed between the two first named layers. The impermeable layer may be natural if the soil consists of clay. The foundation layer c may be composed of broken up bricks, the intermediate spaces or interstices being filled up lwith brick powder or even better with kieselguhr, or ashes either in a dry state or by the aid of water. The broken-up bricks form the carrying means, while the brick powder or kieselguhr on account of its water-absorbing capacity serves for taking up and giving oli' the moisture to the covering layer a.
Tn the construction .shown in Fig. l the foundation layer is provided with a plurality of drain pipes c having a certain amount of slope and connected with one an other, one of them leadingv into a vertical drain pipe f; In front ofthe outlet is provided a sluice valve g, as the case may be, which prevents or limits or allows the runningoff of Water taken up by the drain pipes 6.
The tennis court shown in Fig. 2 has an inclined impermeable layer Z). The inclination is greatest near the edge, and at this place is arranged the vertical drain pipe having a branch L open to the foundation layer c. The valve g is arranged in this branch pipe.
ln both cases by the aid of the valve g the amount of moisture or water within the foundation layer o may be regulated at will.
T claim z- 1. A conditioning system for hard tennis courts comprising` a lowermost impermeable layer, the playing surface', and an intermediate layer in contact with said surface and said impermeable layer, said intermediate layer being constructed of such material as to take up and retain Water draining through the surface layer, and automatically to maintain a rate of moisture exchange with the surface layer when the latter becomes drier than the adjacent part of the intermediate layer, and means Varying the level of Water in said intermediate layer for varying the rate et moisture exchange.
2. A conditioningsystem for hard tennis Courts comprisinga lowermost impermeable layer, the playing surface, and an intermediatelayer in Contact with said surface and said impermeable layer, said intermediate layer being constructed of such material as to take up and retain Water drained through the surface layer, and automatically to main- 'tain a 'ra-te ont moisture exchange with the surface layer when the latter becomes drier than the adjacent part of the intermediate y layer, and means varying the level of Water in said intermediate layer for Varying the rate'oit moisture exchange, said means coniprising a drain pipe and suitable Valve arranged near the lower regions of said intermediate layer. Y
In testimony whereof I have signed my name to this specification.
ERNST EDUARD MARTIENSSEN. Y