Toy building block puzzle

A toy building block puzzle comprises a plurality of at least five differently shaped building blocks. Each block has a peripheral side wall which may include a plurality of lugs and recesses. The lugs and recesses are shaped and sized to interlock two or more blocks together in a horizontal plane by which puzzles of geometric and alphabetic configurations may be formed.

FIELD OF THE INVENTION 
This invention relates to a toy building block puzzle comprising different 
shapes such as triangles and squares which inter-lock to define a further 
geometric shape, such as a parallelogram or triangle. 
The prior art toy building blocks have many sizes and shapes but 
substantially are square or rectangular with protrusions extending from an 
upper face and cavities defined in a lower face to receive the protrusions 
of another block therein. However, such blocks are basically limited to a 
single plane interconnection., i.e., vertical. Furthermore, as such block 
are square or rectangular, with 90.degree. corners, resulting 
constructions are limited to having 90.degree. corners. 
Thus, it is found that there is a long and unfulfilled need for a toy 
building element having regular and irregular geometric shapes, such as 
squares or triangles. 
SUMMARY OF THE INVENTION 
The present invention comprises a plurality of five individual building 
blocks and each block may have a `C`-shaped lug, a `C`-shaped recess or a 
combination thereof and each hereinafter respectively referred to as a 
"lug" or a "recess." A first block is shaped as a square and has a lug 
formed outwardly at a mediate point in two first opposite edges thereof 
and a corresponding recess, defined at a mediate point in each of two 
second opposite edges. 
A second block is shaped as an isosceles triangle with a first edge having 
a lug formed outwardly at a mediate point thereof, and a recess defined at 
a mediate point in each of the remaining sides. 
A third block is shaped as an isosceles triangle with a first edge having a 
lug formed outwardly at a mediate point thereof, a second edge having a 
second lug extending outwardly therefrom at a mediate point thereof, and a 
third edge with a recess defined at a mediate point thereof. 
A fourth block is shaped as a truncated sector of a circle having three 
straight sides and an arcuate side, each side defining a recess in a 
mediate point thereof. 
A fifth block is shaped as a truncated sector of a circle having three 
straight sides and an arcuate side wherein two opposing straight sides 
each have a lug outwardly formed at a mediate point thereof and the 
remaining straight side and arcuate side each have a recess defined in a 
mediate point thereof. 
Each lug is sized and shaped to engage in a corresponding recess with an 
interference fit thus interlocking the blocks until a user requires them 
separated which can be done by applying an appropriate amount of force. 
Other objects, advantages and novel features of the invention will become 
more apparent from the following description when taken in conjunction 
with the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the drawings, a toy building block puzzle comprises at least 
five different toy building blocks (hereinafter referred to as blocks) 
each block being substantially hollow with an open bottom, a closed top 
wall, the top wall having a generally planar upper surface, and a 
plurality of side walls extending downwardly from the top wall. 
Furthermore, each bloc may have a plurality of `C`-shaped recesses and 
`C`-shaped lugs which are sized and shaped to interlock with each other in 
an interference fit and each `C` having an arc of more than 180.degree.. 
Thus, the blocks may be interlocked by pushing one of the lugs into a 
corresponding recess whereby the blocks will remain interlocked due to the 
interference fit and `C`-shape yet be detachable when a predetermined 
amount of force is applied. 
Furthermore, the blocks are preferably made of plastics material which is 
suitable for injection moulding. 
Referring to FIG. 1, a first bloc 10 is shaped as a square and has a pair 
of lugs 12, each lug 12 formed outwardly at a respective mediate point in 
two first opposite edges thereof and a pair of corresponding recesses 14, 
each recess 14 defined in a respective mediate point in two second 
opposite edges. 
Referring to FIG. 2, a second block 20 is shaped as an isosceles triangle 
with a first edge having a lug 22 formed outwardly at a mediate point 
thereof and a second and a third edge each having a recess 24, defined at 
a mediate point thereof. 
Referring to FIG. 3, a third block 30 is shaped as an isosceles triangle 
with a first and a second edges each having a lug 32 formed outwardly at a 
respective mediate point thereof, and a third edge with a recess 34 
defined in a mediate point thereof. 
Referring to FIG. 4, a fourth block 40 is shaped as a truncated sector of a 
circle, having three straight sides and an arcuate side, each side 
defining a recess 42 in a respective mediate point thereof. 
Referring to FIG. 5, a fifth block 50 is shaped as a truncated sector of a 
circle, having three straight sides and an arcuate side, the opposing 
straight sides each have a lug 52 outwardly formed at a respective mediate 
point thereof and the remaining straight side and arcuate side each have a 
recess 54 defined in a respective mediate point thereof. 
It is to be noted that each straight edge of each block is of a same 
length. 
Building blocks of the present invention provide novelty in the 
configuration of geometric and alphabetic shapes as shown in FIGS. 6 
through 13. 
Although the present invention has been explained in relation to its 
preferred embodiments, it is to be understood that many other possible 
modifications and variations can be made without departing from the spirit 
and the scope of the invention as hereinafter claimed.