Abstract: A cover assembly for a swimming pool is provided which includes a rigid, sturdy deck member which fits over the top of the pool, and which also includes an hydraulic cylinder and linkage coupling the hydraulic cylinder to the deck member so that operation of the cylinder causes the deck member to be lifted clear of the top of the pool, while maintained in a horizontal position, and up to an elevated position, and at the same time shifting the deck member back to a position displaced from the side of the pool. When in its up or down position, the deck member may serve as a sun deck, for example, and when the deck member is in its upper position, it may also serve to provide shade adjacent to the pool.

Abstract: A roller skate wheel for roller skate, or skateboard use, is provided which is formed of an appropriate yieldable plastic material, such as polyurethane, or other suitable material, which is hard but not brittle, and which will deform when subjected to an impact force. Moreover, the plastic material is such that it will instantly restore itself to its original shape after the force has been removed, and it will not acquire a permanent set in a deformed condition. In accordance with the invention, the gripping capabilities of the wheel are enhanced by the provision of a plurality of spaced peripheral grooves in the rim of the wheel, which form a corresponding plurality of peripheral ribs. A pair of side grooves are also provided in the rim of the wheel adjacent to the peripheral surface to permit the end ribs to bend outwardly and improve the grip of the wheel, especially during turning or cornering.

Abstract: A skateboard is provided which is constructed to incorporate a braking device at its rear end for safety purposes; and which also includes in the embodiment to be described, a line tethered to the forward end which may be grasped by the operator, and a foot binding as additional safety features.