Cap and container

Abstract

A container and cap assembly has a container and a cap. The cap covers the container, and has an inner cover, a piston, a slider, and an outer cover. The piston is disposed in the inner cover, and is axially movable therein. The slider is mounted on the piston, and is radially movable to move the piston. The outer cover receives the inner cover, the piston, and the slider. The outer cover is rotated in a first direction to close the container, and is continuously rotated in the first direction to move the slider radially and reciprocatingly so as to move the piston axially and reciprocatingly. The piston is moved to exhaust air from the container to produce a vacuum or approximate vacuum in the container. Therefore, contents in the container are protected from moisture without a desiccant material.

What is claimed is: 
     
         1 . A cap comprising:
 an inner cover;   a piston disposed in the inner cover, and axially movable therein;   a slider mounted on the piston, and radially movable to move the piston; and   an outer cover receiving the inner cover, the piston, and the slider, and   wherein the outer cover is rotatable in a first direction to move the slider radially and reciprocatingly so as to move the piston axially and reciprocatingly.   
     
     
         2 . The cap of  claim 1 , wherein
 the piston further comprises:
 a plug; 
 a sleeve extending from a center of the plug; and 
 two protrusions extend from an outer surface of the sleeve, the two protrusions being opposite to each other; 
   the slider further comprises:
 a body defining a center, and comprising a front side, a rear side, and two lateral sides; 
 a bore formed in the center of the body, and receiving the sleeve of the piston; 
 two guide slots formed in the front and the rear sides of the body respectively, the two guide slots communicating with the bore, and receiving the protrusions of the piston; and 
 two pawls extend from upper portions of the two lateral sides of the body respectively; 
   the outer cover further comprises:
 a top wall; and 
 ratchet teeth extending from a periphery of a bottom surface of the top wall, the ratchet teeth being evenly spaced on the periphery of the bottom surface of the top wall; 
   wherein the outer cover is rotatable in the first direction to cause the ratchet teeth to push the pawls of the slider, such that the slider is moved radially and reciprocatingly, and the piston is moved axially and reciprocatingly; and   wherein the outer cover is rotatable in a second direction to cause the ratchet teeth to engage the pawls of the slider, such that the slider cannot be moved radially, and the piston cannot be moved axially.   
     
     
         3 . The cap of  claim 2 , wherein
 the inner cover further comprises:
 an outer wall; 
 an inner wall disposed within the outer wall; 
 a shaft tube disposed within the inner wall, the shaft tube comprising:
 a top opening configured to be closed by an indicator, and wherein the indicator is able to pop up and pop down; and 
 a bottom opening; 
 
 a top wall closing a top end between the outer wall and the inner wall; 
 a bottom wall closing a bottom end between the inner wall and the shaft tube; and 
 at least one pair of recesses formed in the top wall, the at least one pair of recesses being evenly spaced, and two recesses of each of the pair being opposite to each other; 
   wherein a periphery of the plug of the piston abuts the inner wall of the inner cover;   wherein the sleeve of the piston is disposed around the shaft tube of the inner cover, and an inner surface of a bottom of the sleeve abuts an outer surface of the shaft tube of the inner cover;   wherein the slider comprises two wings extending from middle portions of the lateral sides of the body respectively, and the two wings being disposed in the two recesses of each of the pair of recesses respectively; and   wherein the outer cover comprises a center hole aligned with the top opening of the shaft tube of the inner cover.   
     
     
         4 . The cap of  claim 3 , wherein
 the bottom wall of the inner cover comprises a plurality of first vent holes, and a first valve is movably mounted on the bottom wall of the inner cover, the first valve is configured to close the first vent holes by moving; and   the plug of the piston comprises a plurality of second vent holes, and the second valve is movably mounted on the plug of the piston, the second valve is configured to close the second vent holes by moving.   
     
     
         5 . The cap of  claim 3  further comprising:
 an air filter disc closing the bottom opening of the shaft tube of the inner cover; and 
 a sealing ring mounted on a bottom surface of the top wall of the inner cover. 
 
     
     
         6 . A container and cap assembly comprising:
 a container; and   a cap configured to cover the container, the cap comprising
 an inner cover; 
 a piston disposed in the inner cover, and axially movable therein; 
 a slider mounted on the piston, and radially movable to move the piston; and 
 an outer cover receiving the inner cover, the piston, and the slider; 
   wherein the outer cover is rotatable in a first direction to close the container, and is adapted to be further rotated in the first direction to move the slider radially and reciprocatingly so as to move the piston axially and reciprocatingly, and the piston is moved to exhaust air from the container; and   wherein the outer cover is rotatable in a second direction to open the container.   
     
     
         7 . The container and cap assembly of  claim 6 , wherein
 the piston further comprises:
 a plug; 
 a sleeve extending from a center of the plug; and 
 two protrusions extend from an outer surface of the sleeve, the two protrusions being opposite to each other; 
   the slider further comprises:
 a body defining a center, the body comprising a front side, a rear side, and two lateral sides; 
 a bore formed in the center of the body, and receiving the sleeve of the piston; 
 two guide slots formed in the front and the rear sides of the body respectively, the two guide slots communicating with the bore, and receiving the protrusions of the piston; and 
 two pawls extend from upper portions of the lateral sides of the body respectively; 
   the outer cover further comprises:
 a top wall; and 
 ratchet teeth extending from a periphery of a bottom surface of the top wall, the ratchet teeth being evenly spaced on the periphery of the bottom surface of the top wall; 
   wherein the outer cover is rotatable in the first direction to cause the ratchet teeth to push the pawls of the slider, such that the slider is moved radially and reciprocatingly, and the piston is moved axially and reciprocatingly; and   wherein the outer cover is rotatable in the second direction to cause the ratchet teeth to engage the pawls of the slider, such that the slider cannot be moved radially, and the piston cannot be moved axially.   
     
     
         8 . The container and cap assembly of  claim 7 , wherein
 the inner cover further comprises:
 an outer wall; 
 an inner wall disposed within the outer wall; 
 a shaft tube disposed within the inner wall, the shaft communicating with an interior of the container and comprising:
 a top opening configured to be closed by an indicator, and wherein the indicator is configure to pop up and pop down according to a preset air pressure in the container; and 
 a bottom opening; 
 
 a top wall closing a top end between the outer wall and the inner wall; 
 a bottom wall closing a bottom end between the inner wall and the shaft tube; and 
 at least one pair of recesses formed in the top wall, the at least one pair of recesses being evenly spaced, and two recesses of each of the pair being opposite to each other; 
   wherein a periphery of the plug of the piston abuts the inner wall of the inner cover;   wherein the sleeve of the piston is disposed around the shaft tube of the inner cover, and an inner surface of a bottom of the sleeve abuts an outer surface of the shaft tube of the inner cover;   wherein the slider comprises two wings extending from middle portions of the lateral sides of the body respectively, and the two wings are disposed in the two recesses of each of the pair of recesses respectively; and   wherein the outer cover comprise a center hole aligned with the top opening of the shaft tube of the inner cover.   
     
     
         9 . The container and cap assembly of  claim 8 , wherein
 the bottom wall of the inner cover comprises a plurality of first vent holes, and a first valve is movably mounted on the bottom wall of the inner cover, the first valve is configured to close the first vent holes by moving; and   the plug of the piston comprises a plurality of second vent holes, and the second valve is movably mounted on the plug of the piston, the second valve is configured to close the second vent holes by moving.   
     
     
         10 . The container and cap assembly of  claim 8  further comprising:
 an air filter disc closing the bottom opening of the shaft tube of the inner cover; and 
 a sealing ring mounted on a bottom surface of the top wall of the inner cover for abutting the container. 
 
     
     
         11 . A piston assembly comprising:
 an inner cover;   a piston disposed in the inner cover, and axially movable therein; and   a slider mounted on the piston, the slider being radially movable to move the piston.   
     
     
         12 . The piston assembly of  claim 11 , wherein
 the piston further comprises:
 a plug; 
 a sleeve extending from a center of the plug; and 
 two protrusions extend from an outer surface of the sleeve, the two protrusions being opposite to each other; and 
   the slider further comprises:
 a body defining a center, the body comprising a front side, a rear side, and two lateral sides; 
 a bore formed in the center of the body, the bore receiving the sleeve of the piston; and 
 two guide slots formed in the front and the rear sides of the body respectively, the two guide slots communicating with the bore, and receiving the protrusions of the piston. 
   
     
     
         13 . The piston assembly of  claim 12 , wherein
 the inner cover further comprises:
 an outer wall; 
 an inner wall disposed within the outer wall; 
 a shaft tube disposed within the inner wall; 
 a top wall closing a top end between the outer wall and the inner wall; 
 a bottom wall closing a bottom end between the inner wall and the shaft tube; and 
 at least one pair of recesses formed in the top wall, the at least one pair of recesses being evenly spaced, and two recesses of each of the pair being opposite to each other; 
   wherein a periphery of the plug of the piston abuts the inner wall of the inner cover;   wherein the sleeve of the piston is disposed around the shaft tube of the inner cover, and an inner surface of a bottom of the sleeve abuts an outer surface of the shaft tube of the inner cover; and   wherein the slider comprises two wings extending from middle portions of the lateral sides of the body respectively, and the two wings being disposed in the two recesses of each pair of recesses respectively.   
     
     
         14 . The piston assembly of  claim 13 , wherein
 the bottom wall of the inner cover comprises a plurality of first vent holes, and a first valve is movably mounted on the bottom wall of the inner cover, the first valve is configured to close the first vent holes by moving; and
 the plug of the piston comprises a plurality of second vent holes, and the second valve is movably mounted on the plug of the piston, the second valve is configured to close the second vent holes by moving.