Background Art In general, a conventional bottle containing high- priced contents, such as alcoholic liquors or medical supplies, is equipped with a check valve structure allowing the contents to be discharged to an exterior through an inlet port of the bottle while preventing forged contents from being introduced into the bottle, thereby preventing the circulation of forged products.

However, although the conventional bottle is equipped with the check valve structure, unscrupulous dealers may easily inject forged contents into the conventional bottle by using special tools, such as injectors. Consumers rarely recognize the fraudulence of such dealers, so that consumers who purchase and take the contents of products that have been forged may come to physical harm with economical loss.

In addition, conventional tamper-proof bottle caps are equipped with a plurality of parts including a check valve for preventing the forged contents from being introduced into the bottles, so the manufacturing cost for the tamper-proof bottle may rise and manufacturing

processes for the tamper-proof bottle may be complicated.

Disclosure of the Invention Therefore, the present invention has been made in view of the above-mentioned problems occurring in the prior art, and it is an object of the present invention to provide a tamper-proof bottle cap allowing a user to easily recognize the opening state of a bottle cap by externally displaying the opening state of the bottle cap when the bottle cap is opened once.

Another object of the present invention is to provide a tamper-proof bottle cap capable of saving the manufacturing cost for the tamper-proof bottle cap while simplifying the manufacturing processes for the tamper- proof bottle cap.

To accomplish the above object, according to one aspect of the present invention, there is provided a tamper-proof bottle cap comprising: a bottle plug screw- coupled around a bottle neck formed at an upper end of a bottle and including an opening/closing state display section for displaying an opening/closing state of the bottle; a cap section coupled to an upper portion of the bottle plug and formed with a window for allowing a user to check the opening/closing state display section of the bottle plug, the cap section being rotated relative to the bottle plug for a predetermined period without being separated from the bottle plug; a restricting unit installed between the bottle plug and the cap section so as to fix the bottle plug to the cap section after the cap section has been rotated relative to the bottle plug for the predetermined period; and a fixing unit coupled to a lower portion of the bottle plug so as to allow bottle plug to be fixed to the bottle neck while the cap

section is being rotated relative to the bottle plug for the predetermined period.

According to the present invention, the inner cap is idly rotated for a predetermined period relative to the bottle plug sealing the inlet port of the bottle, while displaying the opening/closing state display section on the upper surface of the bottle plug. Thus, the user can recognize the opening state of the bottle cap if the bottle cap has been opened once, so it is impossible to tamper with the contents of the bottle. In addition, since the inner cap is idly rotated relative to the bottle plug without being separated from the bottle plug, it is impossible to change the opening/closing state display section. Thus, it is impossible to tamper with the bottle cap.

To accomplish the above object, according to another aspect of the present invention, there is provided a tamper-proof bottle cap comprising: an inner cap screw-coupled around a bottle neck formed at an upper end of a bottle and including an opening/closing state display section for displaying an opening/closing state of the bottle, the inner cap being provided at an outer peripheral portion thereof with stoppers and reverse-rotation restriction ribs; and an outer cap opened at an upper portion of the inner cap and formed with a window for allowing a user to recognize an opening state of the bottle cap based on the opening/closing state display section displayed through the window, the outer cap being provided at an inner peripheral portion thereof with stoppers engaged with the inner cap when the outer cap rotates after an opening state display part is displayed through the window, and reverse-rotation preventing sections positioned corresponding to the reverse-rotation

restriction ribs so as to prevent the outer cap from being reversely rotated.

According to the exemplary embodiment of the present invention, the tamper-proof bottle cap has a dual-cap structure including the inner and outer caps, in which the outer cap is primarily rotated relative to the inner cap so as to allow the user to recognize the opening state of the bottle cap. After that, the outer cap is integrally rotated together with the inner cap while preventing the outer cap from being reversely rotated relative to the inner cap, thereby preventing the fake of the bottle cap.

To accomplish the above object, according to still another aspect of the present invention, there is provided a tamper-proof bottle cap comprising: a screw cap screw-coupled around a bottle neck formed at an upper end of a bottle and including an opening/closing state display section for displaying an opening/closing state of the bottle ; a reverse-rotation preventing ring coupled to an outer peripheral portion of the screw cap and provided at an outer peripheral portion thereof with stoppers and reverse-rotation preventing ribs, which are aligned while forming a predetermined interval therebetween ; and an outer cap opened at an upper portion of the screw cap and the reverse-rotation preventing ring and formed with a window for allowing a user to recognize an opening state of the bottle cap based on the opening/closing state display section when the outer cap is rotated in an opening direction thereof, the outer cap being provided at an inner peripheral portion thereof with stoppers engaged with the screw cap and the reverse-rotation preventing ring when the outer cap rotates after an opening state display part is displayed through the window, and

reverse-rotation preventing sections positioned corresponding to the reverse-rotation restriction ribs of the reverse-rotation preventing ring so as to prevent the outer cap from being reversely rotated.

According to the exemplary embodiment of the present invention, the reverse-rotation preventing ring and the screw cap may act as an inner cap relative to the outer cap, thereby improving productivity.

As described above, according to the tamper-proof bottle cap of the present invention, the fake of the bottle cap can be prevented through a simple structure so that the manufacturing cost becomes reduced and the manufacturing process becomes simplified, thereby improving productivity. In addition, it is impossible to tamper with high-priced contents, such as alcoholic liquors or medical supplies, thereby preventing consumers from physical harm and economical loss.

Brief Description of the Drawings The foregoing and other objects, features and advantages of the present invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings in which: FIG. 1 is an exploded perspective view illustrating a tamper-proof bottle cap according to a first embodiment of the present invention; FIG. 2 is an exploded sectional view illustrating a. tamper-proof bottle cap according to a first embodiment of the present invention; FIG. 3 is an assembled view of a tamper-proof bottle cap shown in FIG. 2; FIGS. 4a to 4d are sectional views illustrating relationships between a bottle cap and a bottle plug of

a tamper-proof bottle cap according to a first embodiment of the present invention when the tamper- proof bottle cap is opened; FIGS. 5a and 5b are plan views of a tamper-proof bottle cap according to a first embodiment of the present invention when the tamper-proof bottle cap is opened; FIG. 6 is an exploded perspective view illustrating a bottle plug and an inner cap modified from those of the first embodiment of the present invention; FIG. 7 is an exploded perspective view illustrating a tamper-proof bottle cap according to a second embodiment of the present invention; FIG. 8 is an assembled perspective view illustrating a tamper-proof bottle cap according to a second embodiment of the present invention; FIG. 9 is a sectional view taken along line A-A' of FIG. 8; FIG. 10 is a sectional view taken along line B-B' of FIG. 8 ; FIGS. lla and llb are sectional views illustrating the operational state of a tamper-proof bottle cap according to a second embodiment of the present invention; FIGS. 12a and 12b are plan views illustrating the operational state of a tamper-proof bottle cap according to a second embodiment of the present invention; FIG. 13 is a sectional view illustrating a tamper- proof bottle cap modified from that of a second embodiment of the present invention; FIG. 14 is an exploded perspective view illustrating a tamper-proof bottle cap according to a third embodiment of the present invention ;

FIG.'15 is an assembled sectional view illustrating a tamper-proof bottle cap according to a third embodiment of the present invention; FIG. 16 is a longitudinally sectional view illustrating a tamper-proof bottle cap according to a third embodiment of the present invention; FIGS. 17a and 17b are sectional views illustrating the operational state of a tamper-proof bottle cap according to a third embodiment of the present invention ; and FIGS. 18a and 18b are plan views illustrating the operational state of a tamper-proof bottle cap according to a third embodiment of the present invention.

Best Mode for Carrying Out the Invention Hereinafter, a preferred embodiment of the present invention will be described with reference to accompanying drawings.

First Embodiment As shown in FIGS. 1 to 3, a tamper-proof bottle cap according to a first embodiment of the present invention includes a bottle plug 10 screw-coupled around a bottle neck 2 provided at an upper end of a bottle 1 and a cap section provided at an upper portion of the bottle plug 10 in such a manner that the cap section cannot be separated from the bottle plug 10 while allowing a user to check the opening state of the bottle plug 10 if the user rotates the cap section in an opening direction thereof. The cap section includes an outer cap 20 and an inner cap 30.

The bottle plug 10 is provided with a pressing plate 40 for fixing the bottle plug 10 to the bottle neck 2 until an opening state of the cap section is

displayed due to the rotation of the outer and inner caps 20 and 30. An upper surface of the pressing plate 40 has a convex shape and a lower surface of the pressing plate 40 has a concave shape so that the pressing plate 40 is compressed between a bottle inlet port 3 and the bottle plug 10.

The pressing plate 40 is made from flexible plastic. Preferably, the pressing plate 40 is made from silicon. In this case, the pressing plate 40 is pressed towards the bottle inlet port 3 when the outer and inner caps 20 and 30 rotate, thereby fixing the bottle plug 10 to the bottle neck 2. That is, silicon has low attractive force between particles thereof, so silicon may be widely expanded with a thin thickness on a surface of an object. Thus, when the outer and inner caps 20 and 30 rotate, the pressing plate 40 acts as a packing capable of pulling the bottle plug 10.

The bottle plug 10 has a cylindrical structure in which a lower portion is opened. The bottle plug 10 has an upper plate 10a formed at a center thereof with a perforated hole 11. In addition, the bottle plug 10 has a sidewall lOb formed at an inner peripheral portion thereof with a screw-section 12, which is screw-coupled with a screw 2a formed at an outer peripheral portion of the bottle neck 2. An opening/closing state display section 13 is provided at an upper surface of the upper plate 10a so as to display the opening/closing state of the bottle cap.

The opening/closing state display section 13 includes a closing state displaying part 13A and an opening state displaying part 13B, which are radially formed about the perforated hole 11 of the upper plate 10a. The closing state displaying part 13A is marked with a character"CLOSE"or a predetermined color (for

example, blue) and the opening state displaying part 13B is marked with a character"OPEN"or a predetermined color (for example, red).

Three pairs of first and second stoppers 14 and 15 are radially provided at an outer peripheral portion of the upper plate 10a of the bottle plug 10 while forming a predetermined interval therebetween.

The first stopper 14 includes an inclined surface 14a, which is inclined in an opening direction of the bottle plug 10, and a vertical surface 14b formed at a rear portion of the inclined surface 14a. In addition, the second stopper 15 has a hexahedral shape including vertical side surfaces 15a and 15b.

The inner cap 30 of the cap section has a cylindrical structure in which a lower portion is opened such that the cap section is opened at an upper portion of the bottle plug 10. The inner cap 30 has an upper plate 30a formed at a center thereof with a perforated hole 31. In addition, a window 32 having a size corresponding to a half size of the opening/closing state display section 13 is radially formed on the upper plate 30a about the perforated hole 31. The closing state displaying part 13A and the opening state displaying part. 13B are selectively exposed to an exterior through the window 32.

Three pairs of first and second locking protrusions 33 and 34 are formed at a lower surface of the upper plate 30a of the inner cap 30 corresponding to the three pairs of first and second stoppers 14 and 15.

The first locking protrusion 33 includes an inclined surface 33a, which makes surface-contact with the inclined surface 14a of the first stopper 14, and a vertical surface 33b formed at a rear portion of the inclined surface 33a. In addition, the second locking

protrusion 34 has a hexahedral shape including vertical side surfaces 34a and 34b.

The first and second locking protrusions 33 and 34 of the inner cap 30 are spaced from each other by a predetermined distance in such a manner that the first and second locking protrusions 33 and 34 of the inner cap 30 can be disposed between the first and second stoppers 14 and 15.

A support stage 35 is provided at an inner peripheral portion of a lower portion of the inner cap 30 in order to prevent the inner cap 30 from being separated from the bottle plug 10. In addition, a coupling slot 36 is formed at an outer peripheral portion of the inner cap 30. A coupling protrusion 21 of the outer cap 20 is engaged with the coupling slot 36 of the inner cap 30.

The outer cap 20 is coupled with the inner cap 30 such that the outer cap 20 can be integrally rotated with the inner cap 30. An outer portion of the outer cap 20 can be formed with various patters so as to improve an outer appearance of the bottle cap. The outer and inner caps 20 and 30 are provided with stopper ribs, which make contact with each other in order to integrally rotate the outer and inner caps 20 and 30.

The outer cap 20 is made from a transparent material so that the user can check the inner cap 30 from an exterior through the window 32. The outer cap 20 can be integrally formed with the inner cap 30.

The pressing plate 40 is a circular plate having a diameter sufficient for sealing the bottle inlet port 3.

An insertion groove 41, into which the bottle inlet port 3 is inserted, is formed at a lower peripheral surface of the pressing plate 40. In addition, a shaft 42 extending through perforated holes 11 and 31 formed at

centers of the bottle plug 10 and the inner cap 30 is provided at a center of the upper surface of the pressing plate 40. A roof section 43 is formed at an upper end of the shaft 42 so as to prevent the shaft 42 from being separated from the perforated holes 11 and 31.

Hereinafter, an opening operation of the tamper- proof bottle cap according to the first embodiment of the present invention will be described with reference to FIGS. 4a to 4d, 5a and 5b.

In a state in which the bottle inlet port is completely sealed with the bottle cap, as shown in FIG.

5a, the closing state displaying part 13A representing the character"CLOSE"or the blue color is displayed through the window 32 of the inner cap 30 and the outer cap 20. That is, as shown in FIG. 4a, according to the relationship between the bottle plug 10 and the inner cap 30 when the bottle cap is completely closed, the second locking protrusion 34 of the inner cap 30 is positioned between the first stopper 14 and the second stopper 15 of the bottle plug 10, so that the vertical surface 14b of the first stopper 14 makes contact with the vertical side surface 34a of the second locking protrusion 34.

In this state, if the user rotates the bottle cap in the opening direction thereof, only the outer and inner caps 20 and 30 are rotated while the bottle plug 10 is being fixed by means of the pressing plate 40. At this time, as shown in FIG. 4b, the inclined surface 33a of the first locking protrusion 33 of the inner cap 30 makes surface-contact with the inclined surface 14a of the first stopper 14 of the bottle plug 10.

Then, as shown in FIG. 4c, the inclined surface 33a of the first locking protrusion 33 is guided along

the inclined surface 14a of the first stopper 14 of the bottle plug 10, so that the inner cap 30 may upwardly move above the bottle plug 10.

That is, when the inner cap 30 is rotated, the bottle plug 10 is not rotated together with the inner cap 30, but attractive force is applied to the bottle plug 10 by means of the pressing plate 40 making surface-contact with a lower surface of the bottle plug 10, so that the bottle plug 10 can be fixed to the bottle inlet port 3. Since the pressing plate 40 is made from flexible plastic or silicon, the pressing plate 40 may act as a packing, so the bottle plug 10 cannot rotate when the inner cap rotates. That is, only the inner cap 30 may idly rotate while the bottle plug 10 is being maintained in a fixed state.

Such a situation, in which the bottle plug 10 is fixed by means of the pressing plate 40 and the inner cap 30 is idly rotated, may be continued until the locking protrusions 33 and 34 of the inner cap 30 are aligned between the stoppers 14 and 15 of the bottle plug 10.

As shown in FIG. 4d, when the first locking protrusion 33 of the inner cap 30 moves beyond the inclined surface 14a of the first stopper 14 of the bottle plug 10, the first and second locking protrusions 33 and 34 of the inner cap 30 are inserted between the first and second stoppers 14 and 15 of the bottle plug 10, so the bottle plug 10 can be rotated together with the inner cap 30. In this state, as shown in FIG. 5b, the opening state displaying part 13B representing the character"OPEN"or the red color is displayed through the window 32 of the inner cap 30, so the user can recognize the opening state of the bottle cap.

When the inner cap 30 is rotated together with the

bottle cap 10, the vertical surface 33b of the first locking protrusion 33 of the inner cap 30 makes contact with the vertical surface 14b of the first stopper 14 of the bottle plug 10, and the vertical side surface 34b of the second locking protrusion 34 makes contact with the vertical side surface 15a of the second stopper 15, so that the first and second locking protrusions 33 and 34 are press-fitted between the first and second stoppers 14 and 15. Thus, as the user further rotates the cap section, the inner cap 30 is integrally rotated together with the bottle plug 10, so that the bottle inlet port 3 is opened.

If the bottle cap has been opened once, a person cannot replace the opening state displaying part 13B with the closing state displaying part 13A. That is, since the first and second locking protrusions 33 and 34 of the inner cap 30 are press-fitted between the first and second stoppers 14 and 15 of the bottle plug 10, as shown in FIG. 4d, the vertical surface 33b of the first locking protrusion 33 of the inner cap 30 is restricted by the vertical surface 14b of the first stopper 14 and the vertical side surface 34b of the second locking protrusion 34 of the inner cap 30 is restricted by the vertical side surface 15a of the second stopper 15 of the bottle plug 10, so the opening state displaying part 13B cannot be replaced with the closing state displaying part 13A. Accordingly, the opening state displaying part 13B is continuously displayed even if the bottle inlet port 3 is closed by means of the bottle cap. That is, the bottle plug 10 is integrally rotated together with the inner cap 30 in the same direction, so the user can recognize the opening state of the bottle cap through the window 32 of the inner cap 30.

In the meantime, according to another embodiment

of the present invention, as shown in FIG. 6, an opening/closing state display section 13'can be formed at a sidewall lob of the bottle plug 10. In this case, a window 32'is formed at a sidewall 30b of the inner cap 30.

According to this embodiment, the opening operation for the bottle cap is substantially identical to that of the first embodiment. However, the user may recognize the opening state of the bottle cap based on a closing state display part 13'A or an opening state display part 13'B of the opening/closing state display section 13', which can be displayed through the window 32'formed in the sidewall 30b of the inner cap 30.

In addition, it is also possible to form opening/closing state display sections 13 and 13'at both upper plate lOa and sidewall lOb of the bottle plug 10. In this case, windows 32 and 32'are formed in both upper plate 30a and sidewall 30b of the inner cap 30 so as to allow the user to check the opening/closing state of the bottle cap.

Second. Embodiment FIGS. 7 to 9 show a tamper-proof bottle cap 100 according to a second embodiment of the present invention.

As shown in FIG. 7, the tamper-proof bottle cap 100 includes an inner cap 110 screw-coupled with a bottle neck 2 provided at an upper end of a bottle 1 and formed with an opening/closing state display section 112 for displaying the opening/closing state of the bottle cap, and an outer cap 120 which is opened at an upper portion of the inner cap 110 and is formed with a window 122 for allowing a user to recognize the opening/closing state of the bottle cap based on the opening/closing state display section 112 when the upper cap 120 is

relatively rotated in the opening direction with respect to the inner cap 110.

A closing state display part 112A of the opening/closing state display section 112 formed at the upper surface of the inner cap 110 is marked with a character"CLOSE"or a predetermined color (for example, blue) and an opening state displaying part 112B of the opening/closing state display section 112 is marked with a character"OPEN"or a predetermined color (for example, red).

Three stoppers 114 are provided at an outer sidewall of the inner cap 110 while forming a predetermined interval therebetween, and three stoppers 124 are provided at an inner sidewall of the outer cap 120 while forming a predetermined interval therebetween.

A reverse-rotation restriction rib 116 is provided between adjacent stoppers 114 formed at the outer sidewall of the inner cap 110. In addition, a reverse- rotation restriction rib 126 is provided between adjacent stoppers 124 formed at the inner sidewall of the outer cap 120.

Multi-stepped locking parts 116a are provided at a rear portion of the reverse-rotation restriction rib 116 of the inner cap 110, in which the multi-stepped locking parts 116a are inclined and lengths thereof become enlarged in the opening direction of the bottle cap 100, that is, in the counterclockwise direction.

In addition, the reverse-rotation restriction rib 126 formed at an inner peripheral portion and restricted by the reverse-rotation restriction rib 116 is inclined in the direction identical to the inclination direction of the multi-stepped locking parts 116a of the reverse- rotation restriction rib 116, so the outer cap 120 is prevented from being relatively rotated with respect to

the inner cap 110 by means of the reverse-rotation restriction rib 116 and the multi-stepped locking parts 116a.

As shown in FIG. 10, the inner cap 110 and the outer cap 120 are coupled to each other without being separated from each other by means of an anti-separation protrusion 128 provided at a lower end of the outer cap 120.

Hereinafter, an operation of the tamper-proof bottle cap according to the second embodiment of the present invention will be described.

In a state in which the tamper-proof bottle cap 100 is coupled with the bottle neck 2 of the bottle 1, as shown in FIG. lla, the stopper 114 of the inner cap 110 is spaced from the stopper 124 of the outer cap 120, the reverse-rotation restriction rib 126 of the outer cap 120 is positioned at a rear portion of the reverse- rotation restriction rib 116 of the inner cap 110. In addition, as shown in FIG. 12a, the closing state display part 112A is displayed through the window 122 formed on the upper surface of the outer cap so that the user can easily recognize the closing state of the bottle cap 100.

In this state, if the user rotates the bottle cap 100 in order to open the bottle cap 100, the outer cap 120 is primarily rotated with respect to the inner cap 110. At this time, the reverse-rotation restriction rib 126 of the outer cap 120 moves along the multi-stepped locking parts 116a of the bottle plug 110. Since the multi-stepped locking parts 116a of the bottle plug 110 are inclined in the opening direction of the bottle cap and the reverse-rotation restriction rib 126 of the outer cap 120 is inclined in the direction identical to the inclination direction of the multi-stepped locking

parts 116a of the reverse-rotation restriction rib 116, the reverse-rotation restriction rib 126 of the outer cap 120 can move along the multi-stepped locking parts 116a of the reverse-rotation restriction rib 116 without being interrupted by the multi-stepped locking parts 116a of the reverse-rotation restriction rib 116, so that the outer cap 120 is rotated. When the rotation of the outer cap 120 is stopped, the reverse-rotation restriction rib 126 is engaged with the multi-stepped locking parts 116a of the reverse-rotation restriction rib 116, so the reverse-rotation of the outer cap 120 is prevented.

As shown in FIG. llb, when the outer cap 120 rotates until the stopper 124 of the outer cap 120 makes contact with the stopper 114 of the inner cap 110, the reverse-rotation restriction rib 126 of the outer cap 120 has been moved beyond the reverse-rotation restriction rib 116 of the inner cap 110. From this point, the stopper 114 corresponds to the stopper 124 so that the inner cap 110 may rotate together with the outer cap 120.

Since the outer cap 120 has been relatively moved with respect to the inner cap 110, as shown in FIG. 12b, the opening state display part 112B of the inner cap 110 is displayed through the window 122 formed on the upper surface of the outer cap 120, so the user can recognize the opening state of the bottle cap 100.

In addition, since the reverse-rotation restriction rib 126 of the outer cap 120 has been moved beyond the reverse-rotation restriction rib 116 of the inner cap 110, the reverse-rotation restriction rib 126 of the outer cap 120 is restricted by the reverse- rotation restriction rib 116 of the inner cap 110 even if the user forcibly tries to reversely rotate the outer

cap 120 with respect to the inner cap 110, so it is impossible to fake the opening sate of the bottle cap 100.

In addition, the outer cap 120 cannot be longitudinally separated from the inner cap 101 due to the anti-separation protrusion 128 provided at the lower end of the outer cap 120. Thus, forging the bottle cap 100 by separating the outer cap 120 from the inner cap 110 is impossible.

FIG. 13 is an example of the bottle cap modified from the second embodiment of the present invention.

According to FIG. 13, instead of the multi-stepped locking parts 116a, an inclined section 116b is formed at the rear portion of the reverse-rotation restriction rib 116 of the inner cap 110. Accordingly, if the reverse-rotation restriction rib 126 of the outer cap 120 has not been restricted by means of the reverse- rotation restriction rib 116 of the inner cap 110, the outer cap 120 is reversely rotated while moving along the inclined section 116b. However, if the reverse- rotation restriction rib 126 of the outer cap 120 has been moved beyond the reverse-rotation restriction rib 116 of the inner cap 110, the reverse-rotation of the outer cap 120 may be restricted, so it is impossible to fake the opening state of the bottle cap.

Third Embodiment FIGS. 14 to 16 show a tamper-proof bottle cap according to a third embodiment of the present invention.

As shown in FIGS 14 to 16, the tamper-proof bottle cap 200 according to the third embodiment of the present invention includes an inner cap having a screw cap 210 and a reverse-rotation preventing ring 220 and an outer cap 230 formed at an inner peripheral portion thereof

with stoppers 234 and reverse-rotation preventing sections 236.

The screw cap 210 is provided at an upper surface thereof with an opening/closing state display section 212 including a closing state display part 212A and an opening state display part 212B. The outer cap 230 is provided at an upper plate thereof with a window 232.

In addition, coupling protrusions 214 are provided at an outer peripheral portion of the screw cap 210. The coupling protrusions 214 are spaced from each other at an angle of 90°. The reverse-rotation preventing ring 220 is formed at an inner peripheral portion thereof with a coupling slot 226 corresponding to the coupling protrusions 214.

Three reverse-rotation preventing wings 222 are integrally formed with the outer peripheral portion of the reverse-rotation preventing ring 220 while forming a predetermined interval therebetween. Each of the reverse-rotation preventing wings 222 has a latch 224 for preventing the outer cap 230 from being reversely rotated.

According to the tamper-proof bottle cap 200 having the above structure, the screw cap 210 coupled with the reverse-rotation preventing ring 220 may act as an inner cap.

If the bottle cap is not opened, as shown in FIG.

15, the reverse-rotation preventing wings 222 of the reverse-rotation preventing ring 220 are spaced from stoppers 234 of the outer cap 230. In this state, as shown in FIG. 18a, the closing state display part 212A formed on the upper surface of the screw cap 210 is displayed through the window 232 of the outer cap 230, so the user can recognize the closing state of the bottle cap.

If the user rotates the outer cap 230 in the counterclockwise direction in order to open the bottle cap 200, the screw cap 210 and the reverse-rotation preventing ring 220 are securely fixed to the bottle neck 2, and only the outer cap 230 is rotated relative to the screw cap 210 and the reverse-rotation preventing ring 220. At this time, as shown in FIG. 17a, the outer cap 230 makes contact with the outer peripheral portion of the reverse-rotation preventing ring 220. In addition, reverse-rotation preventing sections 236 formed at the inner peripheral portion of the outer cap 230 may rotate while moving along the latches 224 formed at the outer peripheral portion of the reverse-rotation preventing wings 222.

When the outer cap 230 has been rotated at an angle of 120°, as shown in FIG. 17b, the stoppers 234 of the outer cap 230 make contact with front ends 222a of the reverse-rotation preventing wings 222 of the reverse-rotation preventing ring 220. Thus, if the user further rotates the outer cap 230,. the reverse-rotation preventing ring 220 and the screw cap 210 may rotate together with the outer cap 230.

If the screw cap 210 rotates together with the outer cap 230, as shown in FIG. 18b, the opening state display part 212B of the screw cap 210 is displayed through the window 232 of the outer cap 230, so the user can recognize the opening state of the bottle cap 200 from the exterior.

Under the above situation, in which the opening state display part 212B of the screw cap 210 is displayed through the window 232 of the outer cap 230, if the user reversely rotates the outer cap 230 in the clockwise direction, the reverse-rotation preventing sections 236 of the outer cap 230 makes contact with the

latches 224 formed in the reverse-rotation preventing wings 222, so it is impossible to tamper with the opening state of the bottle cap 200 if the bottle cap 200 has been opened once.

In addition, according to the third embodiment of the present invention, as shown in FIG. 16, a support stage 238 is formed at a lower end of the outer cap 230 in such a manner that the reverse-rotation preventing ring 220 and the screw cap 210 from being separated from the outer cap 230, so the fake of the bottle cap 200 can be prevented. It is also possible to provide or form an anti-separation member, which is similar to the support stage, in the outer cap 230 or between the outer cap 230 and the screw cap 210/reverse-rotation preventing ring 220.

Although the second and third embodiments of the present invention illustrate that the opening/closing state display section and the window are formed on the upper surfaces of the inner and outer caps, respectively, it is also possible to form the opening/closing state display section and the window at the sidewalls of the inner and outer caps, respectively.

While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

For instance, the opening/closing state display section provided in the tamper-proof bottle cap according to the present invention can be used not only for displaying the opening/closing state of the bottle cap, but also for displaying prizes or numbers of various events in order to increase purchasing power for

the products.

In addition, according to another embodiment of the present invention, a marking, such as a laser marking, is displayed on a body of the bottle or the bottle neck in relation to the indication of the opening/closing state display section displayed in the bottle cap. That is, an auxiliary unit capable of displaying a mark corresponding to the indication of the opening/closing state display section in the body of the bottle or the bottle neck can be further provided in the bottle cap in order to prevent the fake of the bottle cap.

The auxiliary unit can be used for displaying the prizes or numbers of various events.

Industrial Applicability As can be seen from the foregoing, according to the present invention, the user can easily recognize the opening state of the bottle cap. Accordingly, it is impossible to tamper with high-priced contents, such as alcoholic liquors or medical supplies, thereby preventing consumers from physical harm and economical loss.

In addition, the bottle cap of the present invention can be fabricated through a simple process, so the manufacturing cost for the bottle cap can be reduced. Thus, products equipped with the bottle cap of the present invention can be supplied to consumers at reduced costs.

In addition, the tamper-proof bottle cap according to the present invention can be used for displaying prizes or numbers in various events.