Bicycle tire pressure cap

A bicycle tire pressure cap, used with a bicycle tire valve (10), comprising a metal case (1), an anti-leak washer (2), a ventilation disc (3), a rubber gasket (4), a floating holder (5), a warning plug (6), a spring (7) and a transparent cover (8);

• wherein the metal case (1) sequentially includes an upper orifice (11) and a lower orifice (12) disposed in an upper end of the metal case (1), a lower screw hole (13) disposed in a lower end of the metal case (1) and configured to screw on the tire valve (10), and a small keyhole (14) disposed between the lower orifice (12) and the lower screw hole (13) for connecting therebetween, and an aperture of the upper orifice (11) is larger than that of the lower orifice (12);
• wherein the anti-leak washer (2) is a disc-shaped body having an opening (21) in a center of the washer (2);
• the anti-leak washer (2) is located in the lower screw hole (13), and a top surface of the washer (2) is contacted with an inner bottom side of the lower screw hole (13) and a bottom surface of the washer (2) is contacted with a top edge of the tire valve (10) to prevent air leak;
• wherein the ventilation disc (3) is located in the lower orifice (12), including an air hole (31) in an eccentric position of the ventilation disc (3), and a tenon (32) disposed at a center of a bottom surface the ventilation disc (3) and fitting the tire valve (10) through the opening (21);
• wherein the rubber gasket (4) is a disc-shaped body located in the lower orifice (12) and on a top surface of the ventilation disc (3), including a frame (41) disposed at an edge of the rubber gasket (4), a convex cone (42) disposed in a center of the rubber gasket (4), and a groove (43) between the frame (41) and the convex cone (42);
• a diameter of the rubber gasket (4) is larger than that of the lower orifice (12);
• wherein the floating holder (5) is located at a top of the rubber gasket (4), including a hollow top holder (51) having an upward opening and a hollow bottom holder (52) having a downward opening;
• a diameter of the top holder (51) is greater than a diameter of the bottom holder (52);
• the bottom holder (52) having a bottom edge is-fitted into the groove (43);
• the top holder (51) having an inner bottom surface includes a convex pin (54) in a center of the top holder (51);
• wherein the warning plug (6) is a hollow body, and a bottom end of which is fitted into the top holder (51), including an annular warning zone (61) disposed on an outer surface of the warning plug (6) and has a color different from that of the floating holder (5), a disc (62) disposed at a top end of the warning plug (6), and a sticker (63) affixed to a top surface of the disc (62) and marked with tire pressure;
• wherein the spring (7) includes an upper portion (71) in an upper part of the spring (7) and a lower portion (72) in a lower part of the spring;
• the upper portion (71) is disposed in the warning plug (6) and the lower portion (72) is disposed in the top holder (51) and fitted over the convex pin (54);
• wherein the transparent cover (8) is located on a top end of the metal case (1) and covers the warning plug (6) and floating holder (5);
• the transparent cover (8) includes a hollow cylindrical body (81) and a flange (82) joined to a bottom end of the body (81) and slightly smaller than a diameter of the body (81);
• the flange (82) is inserted into the upper orifice (11), and a bottom edge of which presses an edge of a top surface of the frame (41);
• wherein the disc (62) of the warning plug (6) includes a vent hole (621) disposed at a center of the disc (62);
• the sticker (63) includes a through hole corresponding to the vent hole (621);
• the transparent cover (8) includes a micropore (811) corresponding to the vent hole (621).