Plug for sink drainage

The present invention discloses an optimized plug for a sink drainage to solve the inferior plug shaft and plug knob structure. The plug shaft and plug knob has two engaging structures, namely, rotating engagement and vertically sliding structure; the plug includes a plug body, a plug shaft, a plug knob, and a plug cap, wherein the plug shaft has side slot defined a top end, the plug knob has a trans-slot, a longitudinal annual channel, and knob shoulder and a biasing bridge slidable inserted into the side slot; by rotating the plug cap from 10° to 170° angular degree, the biasing bridge is supported by the top edge of the plug shaft for ensuring the plug in a water-flowing position, while from 171° to 11° degree, the plug knob is slide into the plug shaft for sealing the water; by inserting an elastic member into the trans-slot, the elastic member is adapted to extend out for biasing the plug shaft edge.

What is claimed is:

1. A plug for a sink drainage, comprising:

a hollow plug body fitted into said sink drainage, having an inner platform, and a water stopper attached onto a top surface thereon; and

a plug stem moveably engaged with said plug body for shifting said plug between a water-flowing position and a water-sealing position, comprising:

a circular stem body detachably engaged with said water stopper, having a threaded inner wall and a terrace inwardly projected from a lower portion of said inner wall;

an elongated hollow plug shaft penetrating said stem body to be screwed into said inner platform for coupling said plug stem with said plug body, wherein said plug shaft has a side slot longitudinally defined at a top wall thereof;

a plug knob having a cylinder body, an annular channel longitudinally and upwardly extended from a bottom end of said cylinder body to define an outer wall and an inner core body with said plug knob, a biasing bridge integrally extended between said outer wall and said inner core at an upper portion of said cylinder body, and a knob shoulder circularly flanged from a lower portion of said cylinder body for biasing against said terrace of said circular stem body; and

a plug cap for enclosing said plug shaft and said plug knob within said plug stem, comprising a gripping portion and a lower threaded portion which is correspondingly mated with said threaded inner wall of said stem body;

wherein in said water-sealing position, said plug shaft is inserted into said plug knob by receiving said biasing bridge within said side slot for ensuring said stem body and said water stopper engaged with a water-tight manner, in said water-flowing position, said plug cap is lifted up for pulling said plug knob upwardly shifted along said plug shaft until of said biasing bridge is securely positioned above a top end surface of said plug shaft in a stable manner so as to define a gap between said stem body and said water stopper for draining off said water.

2. The plug, as recited in claim 1, wherein said plug cap is lifted up until a bottom end of said biasing bridge of said plug knob is horizontally aligned with said top end surface of said side slot of said plug shaft, wherein said plug cap is adapted to be rotated within a predetermined angular range for ensuring said biasing bridge supported by a top edge of said plug shaft.

3. The plug, as recited in claim 2, wherein said plug knob further has a trans-slot defined at said cylinder body penetrating said biasing bridge and said inner core for communicating said annual channel to outside via said outer wall.

4. The plug, as recited in claim 3, further comprising a positioning elastic member received within said trans-slot, in said water-flowing position, said plug cap is lift up, said plug shaft is upwardly shifted enabling said trans-slot positioned above said top end surface of said plug shaft, said positioning elastic member is extended out of said trans-slot to be biasing against a top edge of said plug shaft for ensuring said biasing bridge supported by said plug shaft to define said gap between said stem body and said water stopper, in said water-sealing position, said plug knob is downwardly depressed, said positioning elastic member is deformed and pressed into said trans-slot for ensuring said plug knob slidably inserted into said side slot.

5. The plug, as recited in claim 4, wherein said plug body further comprises at least two reinforcement bars defined at a bottom end of said plug body and a bottom opening formed between said reinforcement bars for draining off water in said water-flowing position.

6. The plug, as recited in claim 5, further comprising a retaining collar disposed at a joint portion between said stem body and said plug shaft for ensuring said side slot of said plug shaft secured at a predetermined orientation.

7. The plug, as recited in claim 5, wherein said predetermined angular range is from 10° to 170°.

8. The plug, as recited in claim 4, wherein said predetermined angular range is from 10° to 170°.

9. The plug, as recited in claim 3, wherein said predetermined angular range is from 10° to 170°.

10. The plug, as recited in claim 2, wherein said plug body further comprises at least two reinforcement bars defined at a bottom end of said plug body and a bottom opening formed between said reinforcement bars for draining off water in said water-flowing position.

11. The plug, as recited in claim 10, further comprising a retaining collar disposed at a joint portion between said stem body and said plug shaft for ensuring said side slot of said plug shaft secured at a predetermined orientation.

12. The plug, as recited in claim 2, wherein said predetermined angular range is from 10° to 170°.

13. The plug, as recited in claim 1, wherein said plug knob further has a trans-slot defined at said cylinder body penetrating said biasing bridge and said inner core for communicating said annual channel to outside via said outer wall.

14. The plug, as recited in claim 13, further comprising a positioning elastic member received within said trans-slot, in said water-flowing position, said plug cap is lift up, said plug shaft is upwardly shifted enabling said trans-slot positioned above said top end surface of said plug shaft, said positioning elastic member is extended out of said trans-slot to be biasing against a top edge of said plug shaft for ensuring said biasing bridge supported by said plug shaft to define said gap between said stem body and said water stopper, in said water-sealing position, said plug knob is downwardly depressed, said positioning elastic member is deformed and pressed into said trans-slot for ensuring said plug knob slidably inserted into said side slot.

15. The plug, as recited in claim 14, wherein said plug body further comprises at least two reinforcement bars defined at a bottom end of said plug body and a bottom opening formed between said reinforcement bars for draining off water in said water-flowing position.

16. The plug, as recited in claim 15, further comprising a retaining collar disposed at a joint portion between said stem body and said plug shaft for ensuring said side slot of said plug shaft secured at a predetermined orientation.

17. The plug, as recited in claim 1, wherein said plug body further comprises at least two reinforcement bars defined at a bottom end of said plug body and a bottom opening formed between said reinforcement bars for draining off water in said water-flowing position.

18. The plug, as recited in claim 1, further comprising a retaining collar disposed at a joint portion between said stem body and said plug shaft for ensuring said side slot of said plug shaft secured at a predetermined orientation.