KR20020018909A - Device for protecting cap from open using shape memory alloy and method of making it - Google Patents

Abstract

PURPOSE: A cap protecting device using shape memory alloy and a manufacturing method thereof are provided to allow a cap of an injector to be selectively separated according to a circumference temperature. CONSTITUTION: In an injector container(20) used to receive an injection and provided with a plug(22) for preventing the leakage of the injection, the cap protecting device comprises a cap(30) to be attached to the top portion of the injector container for preventing the separation of the plug; a stopper(32) integrated with the cap in a separable manner; and a shape memory alloy coupled to the stopper. The separation restraint device keeps both ends flaps of the stopper at a second position if a temperature around the injector container is lower than a desired critical temperature, and on the other hand, keeps the both ends flaps at a first position if the temperature is higher than the critical temperature, thus allowing the cap to be selectively separated according to the circumference temperature.

Description

Cap protection device using shape memory alloy and manufacturing method thereof {DEVICE FOR PROTECTING CAP FROM OPEN USING SHAPE MEMORY ALLOY AND METHOD OF MAKING IT}

The present invention relates to a cap protection device using a shape memory alloy and a method for manufacturing the same, and more particularly, a stopper using a shape memory alloy that is deformed into a first shape or a second shape according to ambient temperature at a low temperature such as an injection bottle. When installed in the cap of a container that needs to be sealed, the stopper maintains the second shape during refrigeration, allowing the injection bottle cap to be removed, while the stopper maintains the first shape at room temperature, thereby leaving the cap such as an injection bottle. It relates to a cap protection device using a shape memory alloy for restraining and a method of manufacturing the same.

For example, a container for storing various medicines, such as injection bottles containing injectable drugs, has a stopper fitted at the upper inlet to prevent leakage and deterioration of stored drugs and to prevent foreign substances from entering the outside, and the stopper is detached during storage and transportation. It is capped to prevent opening and to indicate whether it is opened.

1 shows a conventional injection liquid container. In view of the overall configuration, the injection bottle 10, which stores the injection medicine, the stopper 12 fitted to the upper inlet of the injection bottle 10, and the stopper 12 are prevented from being detached. It consists of a sleeve 14 to be manufactured and a cover 16 made of plastic or aluminum. At the time of assembly, the liquid medicine is injected into the injection vial 10, and then a rubber stopper 12 is inserted into the vial of the vial. Next, the cover 16 is fitted with the sleeve 14 to which the cover 16 is press-fitted, and then the lower end of the sleeve 14 is pressed against the inlet edge of the injection bottle 10 so as not to be detached.

However, the vial cap of this structure maintains a constant shape regardless of the ambient temperature at all times, so that the storage state cannot be easily identified by the eye, and thus, the deterioration of the drug is concerned when the vial is stored at room temperature for a long time. . In addition, since the cap can not be clearly identified by the naked eye there is a disadvantage that can not easily determine whether the drug in the injection bottle is genuine.

In view of this point, an injection bottle cap indicating whether a drug stored in an injection bottle is genuine is disclosed in US Pat. No. 5,555,988. The injection or infusion bottle disclosed herein is provided with a cap indicating whether it is genuine, the cap having a hole formed therein and the edge of the hole folded inwardly so that the cap is disposed between the holding portion and the seal, and the cap on the seal. It has a structure in which peripheral beads are formed to support them.

The injection bottle cap disclosed in the patent '988 has a structure that can prevent the phenomenon of falling into the neck portion of the bottle while the seal is deformed and slipped, but also, it is not easy to determine whether the cap is opened, Since refrigeration or room temperature storage cannot be discriminated with the naked eye, there is a concern that the drug may be altered.

An object of the present invention for solving such a problem is to configure the cap to be selectively removed according to the ambient temperature in which the injection bottle is stored to prevent the separation of the cap at room temperature, while refrigerated storage or environment below the critical temperature It is to provide a cap protection device using a shape memory alloy with a separate paper-making means to remove the cap only under the.

Another object of the present invention is to make the shape of the stopper attached to the cap made of the shape memory alloy into the second shape and the first shape according to the ambient temperature so that the storage condition of the injection bottle can be easily visually determined. The present invention provides a cap protection device using a shape memory alloy having display means.

Still another object of the present invention is to provide a cap manufacturing method of an injection liquid container having a stopper function that prevents the cap from being separated at room temperature above a predetermined threshold temperature and allows the cap to be separated during refrigerated storage below a predetermined threshold temperature. have.

Still another object of the present invention is to manufacture a cap of an injection liquid container having a display function capable of indicating the ambient storage temperature of an injection medicine bottle to the outside using a shape memory alloy deformed into a predetermined first shape and a second shape according to the ambient temperature. To provide a method.

1 is an exploded perspective view showing the structure of a conventional injection bottle,

Figure 2 is an exploded perspective view showing an injection vial with a cap protection device according to the invention,

3 is a perspective view showing a planar state of the cap before the capping,

Figure 4 is a perspective view showing a state in which the cap is assembled in Figure 3 capping to maintain the second shape in the injection bottle,

Figure 5 is a cross-sectional view showing the internal structure of the injection bottle shown in Figure 4,

6 is an enlarged cross-sectional view of the cap portion of FIG.

7 is a bottom view of the cap holding the second shape of the shape memory alloy;

8 is a perspective view showing a state in which the stopper maintains the first shape above a predetermined threshold temperature;

9 is an internal cross-sectional view of the injection bottle shown in FIG. 8;

10 is a perspective view showing a state in which the stopper is removed to use the injection medicine;

11 is an internal cross-sectional view of the injection bottle shown in FIG. 10;

12 is a perspective view showing a state in which the stopper is completely removed from the injection bottle;

FIG. 13A is a cross-sectional view showing a shape memory alloy of a cap protection device according to another embodiment of the present invention holding a second shape, and FIG. 13B shows a state in which the shape memory alloy maintains a first shape. It is a cross section.

♣ Explanation of symbols for main part of drawing ♣

20: Vial 22: Stopper

24: Sleeve 30: Cap

32: stopper 34: through hole

35: flap 40: protrusion

50, 60: gypsum suppression alloy

Cap protection device using a shape memory alloy according to the present invention for achieving the above object is in the injection liquid container in which a medicament such as injection drugs are stored and a stopper is inserted at the upper inlet to prevent leakage of the injection drugs, preventing the departure of the stopper A cap attached to the upper portion of the vial for injection, a stopper integrally formed with the cap to be separated by an external force, and the flap coupled to the stopper to hold the flap at both ends of the stopper in a second position below a predetermined threshold temperature. And a separation restraining means for holding the flap at both ends of the stopper at a first position above a predetermined threshold temperature to selectively separate the cap according to the ambient storage temperature.

Cap protection device using a shape memory alloy according to the present invention for achieving the above another object is in the injection liquid container in which a medicament such as injection medicine is stored and a stopper is inserted at the upper inlet to prevent leakage of the injection medicine, preventing the departure of the stopper A cap attached to the upper portion of the vial for injection, a stopper integrally formed with the cap to be rotated according to the ambient temperature, and a flap at both ends of the stopper connected to the stopper at a predetermined threshold temperature or less to a second position. And holding means at both ends of the stopper at a first position above a predetermined threshold temperature to indicate an ambient storage temperature.

Cap manufacturing method using a shape memory alloy according to the present invention for achieving the above another object is a cap manufacturing method of an injection liquid container for storing a drug, such as injection medicine, having a through hole in the center surrounding the through hole Forming a cap to have at least one bridge in the circumferential wall, Capping step of forming a stopper by cutting the bridge of the formed cap so that the flaps of both ends can be separated by an external force, and the stopper at a predetermined threshold temperature or less The flap at the lower end of the stopper, holding the flap at the second end of the stopper and holding the flap at both ends of the stopper at the first position above the predetermined critical temperature to selectively separate the cap according to the ambient storage temperature. And attaching the cap to the upper portion of the cylindrical sleeve to which the separating restraining means is attached. It is characterized by.

In addition, the cap manufacturing method of the injection liquid container according to the present invention for achieving the above another object in the cap manufacturing method of the injection liquid container for storing a drug, such as injection medicine, having a through-hole in the center surrounding the through hole Molding the cap to have at least one bridge in the circumferential wall, and the flaps at both ends are formed to have any one of a first shape above a predetermined threshold temperature and a second shape below a predetermined threshold temperature according to an ambient storage temperature. A capping step of cutting the bridge of the cap to form a stopper; and keeping the flaps at both ends of the stopper at a first position above a predetermined critical temperature, and maintaining the flaps at both ends of the stopper at a second position below a predetermined threshold temperature. Attaching a display means to indicate a temperature to a lower portion of the capped stopper, and the cap to which the display means is attached. It characterized in that it comprises the step of coupling to the top of the cylindrical sleeve.

Hereinafter, with reference to the accompanying drawings will be described in detail a cap protection device using a shape memory alloy according to a preferred embodiment of the present invention and a manufacturing method thereof.

First, Figure 2 shows the structure of an injection vial provided with a cap protection device of the present invention as an example. In this embodiment, the structure of the cap is selectively changed according to the ambient temperature being stored, and the shape of the cap is varied according to the current ambient storage temperature.

To this end, the cap 30 for restraining the detachment of the stopper 22 that is fitted to the top inlet of the injection vial 20 is configured to separate from the cylindrical sleeve 24, the cap 30 to the ambient storage temperature Therefore, the stopper 32 is formed so that the position is variable so that an external force can be selectively applied. In addition, the stopper 32 maintains the flap 35 at both ends of the stopper 32 in the first position at or above the predetermined threshold temperature, and the flap 35 at both ends of the stopper 32 is kept at the second position at or below the predetermined threshold temperature. It was attached to the separation restraining means to maintain and selectively enable the separation of the cap 30 in accordance with the ambient storage temperature.

Here, the separating and restraining means is attached to the lower portion along the longitudinal direction of the stopper 32, the flap 35 at both ends of the stopper 32 is maintained in the second position below the critical temperature to allow the inflow of the user's finger or the like. The shape memory alloy 50 having a predetermined first shape so as to have a predetermined second shape so that the flap 35 at both ends of the stopper 32 is held at the first position at a temperature higher than the critical temperature so as to prevent the inflow of a user's finger or the like. Was used.

Usually, the metal material is plastically deformed at an elastic limit or higher, and after plastic deformation, the shape permanently deformed is maintained even after the external force is removed. On the other hand, it is well known that the shape memory alloy has a property of deforming at a yield point to cause a deformable degree, and returning to a shape before deformation when heated or lost. This shape memory alloy has been used throughout the industry because of its wide variety of uses, and in particular, it can be a device having a predetermined characteristic because the shape memory heat treatment is performed according to a predetermined purpose in relation to temperature. It is possible to keep.

By integrally attaching the shape memory alloy 50 having these characteristics to the stopper 32, the shape memory is stored in the case where the ambient temperature of the medicine bottle 20 is kept below the critical temperature, such as refrigeration or freezing temperature. Alloy 50 will have a second shape. Therefore, the flaps 35 at both ends of the stopper 32 are held in the second position so that the user can put his or the like finger under the flap 35. On the other hand, when the ambient temperature is above the critical temperature, such as room temperature, the shape memory alloy 50 has a first shape. As a result, the flaps 35 at both ends of the stopper 32 are held in the first position so that the user cannot insert the finger under the flap 35, and as a result, the flap 35 is held to hold the stopper 32. It becomes impossible to remove from the cap 30.

The stopper 32 having such a role is integrally formed to rotate to the cap 30 at the time of capping, and a through hole 34 is formed in the center of the stopper 32. In addition, the flap 35 at both ends of the stopper 32 is made by cutting a part of the circumferential wall 33 of the cap 30 at the time of capping.

In the shape memory alloy 50 which rotates the stopper 32 to the first position and the second position according to the ambient temperature, a protrusion 52 is formed at the center thereof so that the center through hole 34 of the stopper 32 is assembled at the time of assembly. It is fixed to insert. In addition, the extension portion 54 of the shape memory alloy 50 extends long along the longitudinal direction of the stopper 32 from the central protrusion 52, and is fixed to the lower surface of the stopper 32 during assembly. The cap 30 to which the shape memory alloy 50 is attached is seated and coupled to the upper coupling flange 24a of the cylindrical sleeve 24 made of aluminum or the like through the flange 31 extending downward from the outer circumferential surface. .

Next, Fig. 3 is a plan perspective view of the cap member molded for producing the cap protection device according to the present invention, showing the state before capping.

Through a molding process such as casting or press working, the central circular portion 32a of the cap member is formed with a through hole 34 through which the central protrusion 52 of the shape memory alloy 50 penetrates. On both sides of the central circular portion 32a of the formed stopper 32, support protrusions 38 extend outwardly. The support protrusion 38 is fixed on the inner wall surface of the circumferential wall 33, and supports the flap 35 at both ends of the stopper 32 so as to be rotatable up and down by the action of the shape memory alloy 50. At the same time, the stopper 32 is removed from the cap 30 while being separated from the circumferential wall 33 when the injection liquid is injected.

In addition, in order to provide the flaps 35 at both ends of the stopper 32, a portion of the circumferential wall 33 is formed with a bridge 36, which is cut during the capping process so that the flap 35 is formed. It serves as. Even after capping, the support protrusion 38 maintains the state fixed to the inner wall of the circumferential wall 33 so that the flaps 35 at both ends of the stopper 32 can be rotated up and down by the shape memory alloy 50. The bridge 36 stores and restrains the shape memory alloy that has been shaped to maintain the first shape at room temperature, and maintains the second shape even at the time of circulation at room temperature. It is designed to maintain the second shape even when cut.

In summary, forming the cap 30 to have at least one bridge 36 in the circumferential wall 33 having the through hole 34 in the center and surrounding the through hole 34, and both ends, A capping step of forming the stopper 32 by cutting the bridge 36 of the cap 30 formed so that the flap 35 can be separated by an external force, and flaps at both ends of the stopper 32 below a predetermined critical temperature. A shape memory for maintaining the cap 35 at the second position and holding the flap 35 at both ends of the stopper 32 at the first position above the predetermined threshold temperature to selectively separate the cap 30 according to the ambient storage temperature. Attaching the separating restraining means and the marking means made of the alloy 50 to the lower portion of the capped stopper 32, and coupling the cap 30 with the separating restraining means to the upper portion of the cylindrical sleeve 24. consist of.

The cap 30 completed through this capping process is assembled on the circular sleeve 24 as shown in FIGS. 4 and 5. In this case, a stopper 22 is fitted at the upper end of the injection bottle 20 containing the chemical liquid, and a circular sleeve 24 is disposed outside the stopper 22 and a stopper at the upper part of the sleeve 24. A cap 30 with 32 is arranged. In the present specification, the sleeve 24 is described as a separate part by separating the cap 30 from the cap 30 for the purpose of description, but the parts in which the sleeve 24 and the cap 30 are assembled are referred to as a normal cap. do. At this time, the shape memory alloy 50 is fixed to the stopper 32 by the fixing piece 40 is shown in detail in FIGS. 6 and 7.

As shown in these figures, after assembly, the lower end 24b of the cylindrical sleeve 24 is pressed onto the upper flange 20a of the injection bottle 20, and the coupling flange 24a at the upper end of the cap 30 of the present invention. ) Is fixed fixedly coupled. The cap 30 has a stopper 32 manufactured as described above integrally formed by the support protrusion 38, and a plurality of fixing pieces (two in the present embodiment) are provided below the stopper 32. 40, the shape memory alloy 50 is attached.

Here, the fixing piece 40 protrudes downward from the central circular portion 32a of the stopper 32. Therefore, in assembling, the shape memory alloy 50 is disposed between the two fixing pieces 40, and then the fixing pieces 40 are bent at approximately right angles to fix the shape memory alloy 50. At this time, the shape memory alloy 50 attached to move the flap 35 at both ends of the stopper 32 up and down is formed slightly longer than the length of the stopper 32 in the drawing, the set threshold temperature and the shape memory alloy What is necessary is just to set it suitably in consideration of thickness and width. When the flap 35 of both ends of the stopper 32 is forcibly pushed up for the use of the injection liquid, it is possible to flip the upper part by the step of the circumferential wall 33, but the step is destroyed when it returns to the original position downward. . This confirms the use of the injection solution to prevent accidents in advance.

Next, the operating principle of the cap protection device of the present invention will be described with reference to FIGS.

First, FIG. 8 and FIG. 9 show a state in which the stopper 32 is kept at the first position because it is left at a predetermined temperature or above a threshold temperature for a predetermined time. As described above, the shape memory alloy 50 maintains the first shape above a predetermined threshold temperature. At this time, both ends of the shape memory alloy 50, the extension portion 54 is maintained in the contracted downward state around the central protrusion 52, accordingly, the stopper 32 is attached to the shape memory alloy 50 Both ends of the flap 35 is to maintain the first position is lowered downward. As a result, it is impossible to insert a finger or other tool into the lower portion of the flap 35 at both ends, whereby the stopper 32 cannot be removed at room temperature above the critical temperature.

In this state, the stopper 32 is held in the first position by the shape memory alloy 50, so that the user can easily grasp the ambient temperature stored by the naked eye by looking at the position of the stopper 32. The cap protection device of the invention also has a function as display means. Therefore, the user can determine the usability of the chemical liquid by looking at the position of the flap 35 at both ends of the stopper 32.

Next, FIGS. 10 and 11 are perspective views in which the stopper 32 removes the flap 35 of the stopper 32 for using the chemical liquid stored at the freezing / refrigerating temperature or below the critical temperature.

As described above, the shape memory alloy 50 maintains the second shape below the predetermined threshold temperature. At this time, both ends of the shape memory alloy 50, 54 is maintained at the equilibrium state around the central protrusion 52 when capping. In this state, a finger etc. can be put in the lower part of the flap 35 at both ends, and the puller 32 can be pulled out in the state which grasped the flap 35 with a finger. Accordingly, the stopper 32 can be completely separated from the cap 30 as shown in FIG.

In addition, since the stopper 32 is maintained in the second position by the shape memory alloy 50, the user can easily check the refrigerated storage state of the injection bottle by visually looking at the position of the stopper 32.

In addition, the stopper 32 may be configured to be completely separated from the cap 30 in use, but both ends of the support protrusion 38 may have a width or a thickness larger than the other side in order to protect the environment and recycle. Among the supporting projections 38, the smaller width or thickness is separated and the opposite side is attached as it is, so that the stopper 32 is preferably configured to be attached to the cap 30 after removal.

Next, Figure 13 is a view showing a cap protection device according to another embodiment of the present invention, Figure 13a is a state in which the shape memory alloy of the cap protection device according to another embodiment of the present invention maintains the second shape 13B is a sectional view showing the state in which the shape memory alloy maintains the first shape.

In the present embodiment, instead of the rod-shaped memory alloy, a circular shape memory alloy ring 60 is illustrated. The shape memory alloy ring 60 is disposed in a state of wrapping a circumferential wall on which a stopper 32 'is formed, and at a temperature below its critical temperature, as shown in FIG. While having a predetermined second shape, the ring 60 'is positioned under the flap 35' at both ends of the stopper 32 'while being contracted in the direction of the arrow as shown in FIG. 13B above the critical temperature. It has a first shape shrunk to restrain the inflow of a finger or the like.

According to the present invention described above, the injection bottle cap is provided with a display means for indicating the storage temperature, so that it is easy to visually identify the storage state of the drug, the shape memory in the injection bottle cap containing the injection liquid A stopper with an alloy is provided, so that the cap can be removed by maintaining the second shape below the predetermined critical temperature at the time of refrigeration, and the cap can be restrained by maintaining the first shape at room temperature above the predetermined critical temperature. have. In addition, since the stopper can be completely removed from the cap during use, there is an advantage that the presence or absence of the cap can be easily confirmed by clearly distinguishing the open state of the cap.

Claims (12)

In an injection liquid container in which a medicament such as an injection medicine is stored and a cap which prevents leakage of the injection medicine is fitted at the upper inlet, A cap attached to the upper portion of the vial to prevent detachment of the stopper; A stopper formed integrally with the cap to be separated by an external force, The cap is coupled to the stopper to maintain the flap at both ends of the stopper at the second position below the predetermined threshold temperature, and to maintain the flap at both ends of the stopper at the first position above the predetermined threshold temperature, thereby selectively separating the cap according to the ambient storage temperature. Cap protection device using a shape memory alloy characterized in that it comprises a separate papermaking means enabling. The method of claim 1, The separating and holding means is attached to the lower portion along the longitudinal direction of the stopper, and below its critical temperature, both ends of the stopper are held in a second position to have a predetermined second shape so as to restrain the inflow of a user's finger or the like. Above the temperature, the cap protection device using the shape memory alloy, characterized in that the flap at both ends of the stopper is a shape memory alloy having a predetermined first shape so as to restrain the inflow of the user's finger or the like. The method of claim 2, The stopper has a shape memory, characterized in that a support protrusion for supporting both ends of the stopper is selectively moved to the first position and the second position by the action of the shape memory alloy while both ends are fixed to the inner wall of the circumferential wall. Cap protector made of alloy. The method of claim 2 or 3, And the shape memory alloy is fixed to move integrally with the stopper by a fixing piece protruding from the bottom of the stopper. The method of claim 1, The shape memory alloy is disposed in a state of enclosing the circumferential wall in which the stopper is formed, and has a second shape extended to remove the stopper below the critical temperature and contracted so that the stopper cannot be removed above the critical temperature. Cap protection device using a shape memory alloy, characterized in that the circular shape memory alloy ring having a shape. In an injection liquid container in which a medicament such as an injection medicine is stored and a cap which prevents leakage of the injection medicine is fitted at the upper inlet, A cap attached to the upper portion of the vial to prevent detachment of the stopper; A stopper formed integrally with the cap to be rotated according to the ambient temperature, And a display means coupled to the stopper to maintain the flap at both ends of the stopper at a second position below a predetermined threshold temperature, and to maintain the flap at both ends of the stopper at a first position above a predetermined threshold temperature to indicate an ambient storage temperature. Cap protection device using a shape memory alloy, characterized in that. The method of claim 6, The display means is attached to the lower portion along the longitudinal direction of the stopper, and below its threshold temperature, the predetermined second temperature is indicated to indicate that flaps at both ends of the stopper are held in the second position and are in normal storage below a predetermined threshold temperature. Cap having a shape and a shape memory alloy having a predetermined first shape to indicate that the flap at both ends of the stopper at the first position and left for a predetermined time above the critical temperature above the critical temperature. Protection. The method of claim 7, wherein The stopper has a support protrusion for supporting both ends of the stopper to be selectively moved to the first position and the second position by the action of the shape memory alloy while both ends are fixed to the inner wall of the circumferential wall. Cap protection device using a shape memory alloy, characterized in that the fixing piece is formed to protrude so as to be movable. In the cap manufacturing method of the injection liquid container for storing a drug such as an injection drug, Forming a cap having at least one bridge in the circumferential wall surrounding the through hole with a through hole in the center; A capping step of forming a stopper by cutting a bridge of a cap formed so that flaps at both ends thereof can be separated by an external force; A separation restraining means which maintains the flap at both ends of the stopper at a second position below a predetermined threshold temperature, and maintains the flap at both ends of the stopper at a first position above a predetermined threshold temperature to selectively separate the cap according to a critical temperature. Attaching to the bottom of the capped stopper; A cap manufacturing method using a shape memory alloy, characterized in that it comprises the step of coupling the cap attached to the upper portion of the cylindrical sleeve with a separate papermaking means. The method of claim 9, The separating and stopping means has a predetermined second shape such that the flaps at both ends of the stopper are kept at the second position below the critical temperature thereof so as to allow the inflow of a user's finger or the like. Is a shape memory alloy having a predetermined first shape so as to be held in the And fixing the shape memory alloy to move integrally with the stopper using a fixing piece protruding from the bottom surface of the stopper. In the cap manufacturing method of the injection liquid container for storing a drug such as an injection drug, Forming a cap having at least one bridge in the circumferential wall surrounding the through hole with a through hole in the center; A capping step of forming a stopper by cutting a bridge of a cap formed such that the flaps at both ends have a shape of one of a second shape below a predetermined threshold temperature and a first shape above a predetermined threshold temperature according to an ambient storage temperature; Lower than the stopper capping the display means to maintain the flap at both ends of the stopper in the second position below the predetermined threshold temperature and to maintain the flap at both ends of the stopper in the first position above the predetermined threshold temperature. Attaching to, A cap manufacturing method using a shape memory alloy, characterized in that it comprises the step of coupling the cap attached to the upper portion of the cylindrical sleeve with the display means. The method of claim 11, The display means is attached to the lower portion along the longitudinal direction of the stopper, and has a predetermined first shape to indicate that the flaps at both ends of the stopper are kept at the first position and exposed to room temperature above the critical temperature. A shape memory alloy having a predetermined second shape to indicate that the flaps at both ends of the stopper are held in a second position and are being refrigerated; And fixing the shape memory alloy to move integrally with the stopper by using a fixing piece protruding from the bottom surface of the stopper.