Portable water bottle cap with built-in filter

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.