Abstract: This disclosure describes an attachment apparatus for securing position and elevation of dowels above a vapor barrier without compromising the ability of the vapor barrier to impede vapor seepage. Various embodiments of the attachment apparatus include, but are not limited to, a ring-shaped force-fit attachment apparatus, magnetically coupled plates, a saddle attachment apparatus, a stake with a flange, a self-sealing stake, and a retainer clip attachment apparatus.

Abstract: A rock bolt and a method of installing a rock bolt in a borehole (3) of a rock formation. The rock bolt including an elongate shank (1) and an expansion assembly (2) located at the distal end of the shank. The expansion assembly being expandable to lock the rock bolt in a borehole upon relative forward rotation of the rock bolt. The rock bolt further including stop means (4) to lock the expansion assembly with respect to the rock bolt for conjoined rotation upon a reverse rotation of the rock bolt.

Abstract: The present invention relates to rock bolts which may be used in mining applications. The rock bolt of this invention includes a mechanical anchoring arrangement to facilitate retaining the rock bolt in a borehole, and also a drill bit to enable self drilling of the rock bolt. Rotation of the rock bolt about an axis of the rock bolt in a first direction causes the drill bit to drill into rock and to create a borehole to receive the rock bolt. Subsequently, rotation in the opposite direction actuates a mechanical anchoring arrangement to anchor rock bolt.

Abstract: A unitary gasket component is designed to provide a complex acoustic path for bringing sound to a microphone. The path includes a pre-plenum and apertures to allow external sound into the pre-plenum. The path further includes an acoustic filter communicating with the pre-plenum and defining relatively small openings for sound to exit the pre-plenum. A voice tube extends from the acoustic filter to a microphone plenum, the latter being in direct communication with the microphone.

Abstract: An arrangement for connecting a printed circuit to a plug of the type having a plurality of parallel contacts located on the edge of an insertion block provided with a resilient detent, includes a housing containing the printed circuit, and an opening in the housing for retaining the insertion block therein. A flexible extension of the printed circuit has parallel contacts formed thereon. The flexible extension extends at an angle through the opening so that the parallel contacts thereon make contact with the parallel contacts on an insertion block retained in the opening.

Abstract: A game including a base, nine elongated pegs disposed substantially perpendicularly to the base and arranged on the base in spaced relation in three discrete groupings. There is further provided a plurality of pieces each having a hole therethrough which is adapted to accommodate any one of the pegs. The game is readily adaptable to various types of scoring and hence, the present invention provides a game which may be played at various degrees of difficulty. In one embodiment, the pieces are provided in two sets of equal number and contrasting colors and an extra "wild" piece of a third discrete color is also provided. In a further embodiment, the pieces in the two sets are selectively provided with additional first, second and third indicia to subdivide each of the sets into three subsets.