Child resistant closure with improved assembly

Abstract

The present invention relates to child-resistant closures, and more particularly to child-resistant closures with multiple caps, engaged by two oppositely acting locking system, which offer advantages over the prior art by enabling easier opening, yet remains child-resistant.

We claim: 
     
         1 . A child-resistant cap assembly, comprising:
 a) an inner cap having a dome-shaped top panel having two elevated circular projections on a base of the outer side, one in the center and one on periphery, and inner side consisting of elevated threads and,   b) an outer cap having elevated projections complimentary to the projections of top surface of inner cap, so as to match with each other leading to a locking arrangement which allows the inner cap to move by the force applied on the outer cap in clockwise direction, the elevated projections of outer closure rides over the gradational elevations of inner cap causing slippage of the outer closure over the inner closure leading to free movement, wherein the closure does not contain any stop member;   wherein the elevated projection in the center consists of at least two pieces of helical structures, which progressively increase in height;   wherein elevated projection on the periphery consists of at least two arches, wherein one end of the arch is having gradational elevation in the direction of progressive arches at center and other end form an angle ranging from 0-180° with the base of the outer side of inner cap meant for peripheral locking system;   wherein the inner and outer cap are joined by means of two oppositely acting system, comprising:   i) center cam system, which provide easy closing of the closure on the container without applying much torque and,   ii) outer periphery locking system, which does not allow the children to open the closure with any force or tampering on the closure in any direction.   
     
     
         2 . The child-resistant cap assembly as claimed in  claim 1 , wherein the inner cap comprises outer and inner side, and wherein the outer side is engaged in outer cap and inner side is attached with the container. 
     
     
         3 . The child-resistant cap assembly as claimed in  claim 1 , wherein the central elevated projection consists of at least two pieces of helical structures, which progressively increase in height and form an angle ranging from 0-180° with the base. 
     
     
         4 . The child-resistant cap assembly as claimed in  claim 1 , wherein the peripheral arches are like pockets, which are formed with rigid border of plastic material having an empty space within the border. 
     
     
         5 . The child-resistant cap assembly as claimed in  claim 1 , wherein the inner side of outer cap consists of at least two projections at periphery, wherein each projection is pocket type made with rigid border of plastic material having an empty space within the border and further the width of which is less than the gap between the peripheral arches of top portions of inner cap. 
     
     
         6 . The child-resistant cap assembly as claimed in  claim 1 , wherein the central surface of the inner side of the outer cap consists of at least two pieces helical structures, which progressively increase in height and form an angle ranging from 0-180° with the base. 
     
     
         7 . The child-resistant cap assembly as claimed in  claim 1 , wherein the top portions of the inner cap are convex or dome-shaped in nature which gives resilient effect and the inner sides of the inner cap consist of threads which encompasses on the complimentary threads of container and ensure capping. 
     
     
         8 . The child-resistant cap assembly as claimed in  claim 1 , wherein the downward pressure on the outer cap will overcome the bias of the dome-shaped top panel to place the inner and outer caps in a first axial position wherein the inner and outer caps are coupled thereby allowing rotation of the inner and outer caps in unison to allow removal of the closure. 
     
     
         9 . The child-resistant cap assembly as claimed in  claim 1 , wherein the child resistant closure has an inner cap adapted to be loosely retained within the outer cap of a safety closure to allow relative rotary movement of the inner cap. 
     
     
         10 . The child-resistant cap assembly as claimed in any of the preceding  claims 1 - 7 , wherein the child resistant closure are formed from a plastic material selected from polyvinyl chloride, low or high density polyethylene, polypropylene, polystyrene polyester teraphthalate and nylon.