Patent ID: 7147224

Claim:
A cylindrical sliding block jigsaw puzzle comprising: a cylindrical barrel;. multiple arcuate sliding blocks with substantially equal size and interconnected with one another to construct a pattern on an outer periphery of the cylindrical barrel in a coordinated status and defining an empty area with a size substantially equal to the size of one of the arcuate sliding blocks; and an unslidable block received in the empty area defined by the arcuate sliding blocks and detachably mounted on the outer periphery of the barrel, wherein each arcuate sliding block is movable relative to the cylindrical barrel so that a position of the empty area is changed so as to enable the pattern to be reconstructed, wherein the cylindrical barrel has a hole defined in a face partly defining the empty area, and the unslidable block has a lug formed at an inner side of the unslidable block to extend into the hole of the barrel to position the unslidable block, wherein the barrel has a bar longitudinally formed at an outer periphery of the barrel to partially limit the movement of the arcuate sliding blocks so as to increase difficulty level of reconstructing the pattern, and wherein the arcuate sliding blocks each have an outer portion with multiple pins formed at an inner side of the outer portion, and an inner portion is composed of two segments with the equal size integrally formed together in a nonaligned arrangement, multiple apertures are defined through a first segment to respectively receive the pins for positioning the outer portion on the inner portion to align the outer portion with a second segment of the inner portion, whereby, a groove is defined at two adjacent sides of the arcuate sliding block between the outer portion and inner portion, and a tongue is protruded opposite to the groove and between the outer portion and inner portion.