US Patent 7096634 Block wall system

A block suitable for forming a block wall that is either a retaining wall or an above ground wall. The block includes a front wall extending between upper and lower block surfaces and presenting a first block face. A rear wall is spaced from said front wall and extends between the upper and lower block surfaces and presents a second block face facing away from the first block face. A pair of side walls extend between the front and rear walls and the upper and lower block surfaces, wherein a reference plane spaced from the front and rear walls extend between the pair of side walls. At least one pair of pin slots is formed in the upper block surface, wherein each pin slot of the at least one pair of pin slots is formed in the upper block surface on opposing sides of the reference plane and spaced from the reference plane. An opening is formed in the lower block surface, has a forward facing inner wall intersecting the lower block surface and spaced rearwardly from the reference line and a rearward facing inner wall intersecting the lower block surface and spaced forwardly from the reference plane, wherein the inner walls at the lower block surface are closer to the reference plane than the pin slots.