Portable water bottle cap with built-in filter

1 . A water bottle cap comprising:

a cap configured to be removably coupled to an opening of a water bottle;

a filter receiver connected to the cap at one side thereof;

a filter member received in the filter receiver, the filter member being configured to filter foreign matter contained in water; and

an air introducer connected to the other side of the filter receiver, the air introducer being configured to guide air,

wherein the cap comprises:

a cap fixer constituted by a first circular plate and a first sidewall, the first circular plate having a first through-hole, the cap fixer being cylindrical in shape, the first circular plate being provided at one side thereof with a discharge port protruding by a predetermined length, the first circular plate being provided at the other side thereof with a holder configured to allow fluid communication with the first through-hole and the discharge port, the holder having a predetermined length, the first sidewall having a thread formed at an inner side configured to engage with an outer surface of the opening of the water bottle, the cap fixer being configured to be removably coupled to the opening of the water bottle; and

a cap portion configured to open and close the discharge port in a state of being connected to the cap fixer,

wherein the filter receiver comprises:

an upper support portion fastened to one side of the filter member; and

a side support portion configured to enclose a side surface of the filter member, the side support portion being cylindrical in shape, one side of the side support portion being connected to the upper support portion,

wherein the upper support portion is constituted by a second circular plate and a second sidewall, the second circular plate having a second through-hole, the upper support portion being cylindrical in shape, the second circular plate being provided at one side thereof with a first connector configured to be brought into tight contact with an inner surface of the holder, the first connector being cylindrical in shape, the first connector having a predetermined length, the second circular plate being provided at the other side thereof with a second connector configured to allow fluid communication with the first connector and the second through-hole, and to be sealingly fastened into the one side of the filter member, the second connector having a predetermined length,

wherein the side support portion is provided with a plurality of slits configured to allow water to pass therethrough,

wherein the air introducer comprises:

a first body comprising a third circular plate having a third through-hole and a third connector extending to one side of the third circular plate so as to be brought into tight contact with the other side of the filter member;

a second body located at one side of the first body, the second body having a fourth through-hole configured to allow air to be introduced therethrough;

a ball received in the second body, the ball being located on a same line as the fourth through-hole; and

a spring received in the second body, the spring being configured to support the ball,

wherein air is guided through the third through-hole and the fourth through-hole, and

wherein the first body further comprises:

a first extension located at an edge of the one side of the third circular plate so as to be fixed to the other side of the side support portion of the filter receiver; and

a second extension extending from the other side of the third circular plate toward an interior of the second body.

2 . The water bottle cap according to claim 1 , wherein the first extension is fixed to the side support portion of the filter receiver in a state of being depressed against the side support portion of the filter receiver.

3 . The water bottle cap according to claim 2 , wherein an inner diameter of the first extension is equal to an inner diameter of the side support portion of the filter receiver.

4 . The water bottle cap according to claim 1 , wherein the second body comprises:

a cover constituted by a third sidewall formed in a cylindrical shape, a bottom plate having the fourth through-hole formed therein, and a fourth sidewall configured to connect the third sidewall and the bottom plate to each other;

an inner sidewall located at an inside of the cover, the inner sidewall extending by a predetermined length, the inner sidewall being cylindrical in shape; and

a rib constituted by a plurality of first ribs located on an inner surface of the inner sidewall, the first ribs extending in a height direction while being spaced apart from each other by a predetermined distance and a plurality of second ribs located on an inner upper surface of the bottom plate, the second ribs being radially disposed while protruding by a predetermined height, the second ribs being configured to support one side of the spring, and

wherein the ball is configured to move upwards and downwards along the first ribs above the second ribs.

5 . The water bottle cap according to claim 4 , wherein an upper end of the third sidewall is located under the first extension.

6 . The water bottle cap according to claim 5 , wherein the first extension is fixed to the side support portion of the filter receiver in a state of being depressed against the side support portion of the filter receiver,

wherein an inner diameter of the first extension, an inner diameter of the side support portion of the filter receiver, and an inner diameter of the third sidewall are equal to each other, and

wherein an outer diameter of the side support portion of the filter receiver and an outer diameter of the third sidewall are equal to each other.

7 . The water bottle cap according to claim 5 , wherein the fourth sidewall has an inner diameter gradually decreasing toward the bottom plate.

8 . The water bottle cap according to claim 4 , wherein the second extension is located so as to enclose an outside of the inner sidewall.

9 . The water bottle cap according to claim 4 , wherein the spring is a coil located between the ball and the second ribs.