Simulated grass playing field surface with rubber particle layer and sand layer

Claim 1

In a playing field surface formed of a synthetic pile carpet which is laid upon a base support surface, and has a base sheet with densely arranged upstanding grass simulating synthetic fibers in the general range of between about one-half to two and one-half inches in height above the base sheet, and including a uniform thickness particulate coating covering the base sheet and of a pre-selected height ranging between the full height of the fibers to a short distance below the full fiber height for exposing the tips of the free ends of the fibers so that the coating generally fills the spaces between the fibers to provide an exposed surface which simulates a natural grass and ground surface, the improvement comprising: said particulate covering being divided into an upper layer and a lower layer; the lower layer being formed of relatively resilient particles of a rubber-like material and being of substantial height relative to the overall height of the fibers; and the upper layer being formed of relatively coarse sand-like particles for covering the lower layer and also being of substantial height relative to the overall height of the fibers; whereby the layers and fibers cooperate to provide a natural grass surface appearance, feel and playability and for stabilizing the positions of the layer particles and fibers.