Screw stopper for synthetic plastics material cans

Screw stopper for synthetic plastic cans in the range of 10 liters and above, comprising:

• a pouring spout which is rigidly connected with said synthetic plastic can,
• said pouring spout having a geometric longitudinal axis, an external threading, and an end face with an annular seal thereon,
• a cap for said pouring spout, which is rotatable between a closed position and an open position,
• said cap having an external circumference and an internal threading fitting said external threading on said pouring spout,
• a projecting device projecting from said external circumference of said cap for manual transmission of a torque,
• a connectin device between said pouring spout and said cap, which makes said cap non-loseable and permits rotation of said cap in relation to said pouring spout, and
• the improvement wherein:
• (a) said external threading is provided in three or more sectors in relation to said geometrical longitudinal axis of said pouring spout,
• (b) said internal threading is provided in three or more sectors in relation to said geometrical longitudinal axis of said pouring spout, with said internal threading sectors fitting in circumferential angle into said external threading sectors and vice versa,
• (c) said internal and external threadings have equal pitch, which pitch is high enough that rotation of said cap through 180 degrees plus/minus 30 derees rotates said cap from said closed position to said open position and vice versa,
• (d) said cap has an upper side and said projecting device comprises a handle on said upper side of said cap, said handle being provided with a handle grip that protrudes far beyond said external circumference of said cap and a handle web with an end region pivotably articulated with said cap,
• (e) said connection device includes a retaining ring which guides said cap in a shape-engaging manner and a guide device that is rigidly connected with said pouring spout and guides said retaining ring substantially nonrotatably in relation to said geometrical longitudinal axis, and
• (f) said guide device has a partial region arranged as an arrestor for said handle grip in said closed position of said cap.