Title:
Case Unit
Kind Code:
A1


Abstract:
A case unit C1 includes a case 1 which includes a front surface 11 formed with a take-out opening 19 for taking out an article stored in the case, a cover 2 including a sealing portion 21 for closing the take-out opening 19, and guiding means 30, 31 for enabling the cover 2 to slide relative to the case 1 so that the sealing portion 21 moves reciprocally along the front surface 11. When the sealing portion 21 is positioned in front of the take-out opening 19, the guiding means 30, 31 displaces the sealing portion 21 toward the front surface 11 so that the sealing portion 21 is pressed against the periphery of the take-out opening 19. With this arrangement, the opening and closing of the take-out opening 19 is performed smoothly and easily, and the take-out opening 19 is properly closed even when the sealing portion 21 is worn out. Further, the case unit C1 is suitable for reduction in size and weight.



Inventors:
Uehata, Yoshiharu (Kyoto, JP)
Application Number:
12/382519
Publication Date:
09/24/2009
Filing Date:
03/18/2009
Assignee:
Arkray, Inc. (Kyoto, JP)
Primary Class:
International Classes:
B65D83/00
View Patent Images:



Primary Examiner:
WHITE, DENNIS MICHAEL
Attorney, Agent or Firm:
FISHMAN STEWART PLLC (BLOOMFIELD HILLS, MI, US)
Claims:
1. A case unit comprising: a case for storing an article, the case including a front surface formed with a take-out opening through which the article is to be taken out of the case; a cover including a sealing portion for closing the take-out opening; and guiding means for enabling the cover to slide relative to the case so that the sealing portion moves reciprocally in a first and a second directions along the front surface; wherein, when the sealing portion is moved in the first direction from a position spaced from the take-out opening to a position in front of the take-out opening, the guiding means displaces the sealing portion toward the front surface so that the sealing portion is pressed against a periphery of the take-out opening.

2. The case unit according to claim 1, wherein the periphery of the take-out opening is formed as a tapered surface which is inclined to project forward from the front surface in such a manner that the projecting amount increases as proceeding in the first direction; and wherein, in closing the take-out opening, the sealing portion is pressed against the tapered surface.

3. The case unit according to claim 1, wherein, when the sealing portion is spaced from the take-out opening, the guiding means keeps a surface of the sealing portion inclined with respect to the front surface, and wherein, when the sealing portion is moved to a position in front of the take-out opening to close the take-out opening, the guiding means rotates the cover so that the surface of the sealing portion becomes parallel with the periphery of the take-out opening.

4. The case unit according to claim 2, wherein, when the sealing portion is spaced from the take-out opening, the guiding means keeps a surface of the sealing portion inclined at an angle of inclination which is larger than an angle of inclination of the tapered surface, and wherein, when the sealing portion is moved to a position in front of the take-out opening to close the take-out opening, the guiding means rotates the cover so that the surface of the sealing portion becomes parallel with the tapered surface.

5. The case unit according to claim 1, wherein the guiding means includes a guide groove provided at one of the case and the cover, and a guide projection provided at the other one of the case and the cover and received in the guide groove; and wherein a movement path of the guide projection is defined by the guide groove.

6. The case unit according to claim 5, wherein the case includes a pair of side surfaces at each of which the guide groove is formed; wherein the cover includes a pair of side walls which face the paired side surfaces and at each of which the guide projection is formed; wherein the guide groove includes a front inner wall and a rear inner wall facing each other and extending in the first and the second directions, the front inner wall being formed with a projecting wall portion projecting toward a rear end of the case; and wherein, when the sealing portion is moved to a position in front of the take-out opening, the guide projection is guided toward the rear end of the case by the projecting wall portion so that the sealing portion is pressed against the periphery of the take-out opening and maintains the pressed state.

7. The case unit according to claim 6, wherein the guide projection extends in a longitudinal direction of the guide groove; and wherein, when the sealing portion moves while being spaced from the take-out opening, at least longitudinally opposite ends of the guide projection are held in contact with one of the front inner wall and the rear inner wall, whereas a longitudinally intermediate portion of guide projection is held in contact with the other one of the front inner wall and the rear inner wall, so that posture of the cover is substantially maintained.

8. The case unit according to claim 6, wherein the projecting wall portion is provided at a position spaced from the take-out opening in the first and the second directions; and wherein, when the guide projection is guided by the projecting wall portion to be displaced toward the rear end of the case, the cover rotates so that the sealing portion is pressed against the periphery of the take-out opening.

9. The case unit according to claim 1, wherein the article to be stored in the case is an analytical tool used for analyzing a sample; wherein the case unit further comprises positioning means provided in the case for supporting a plurality of analytical tools stacked in a thickness direction of the tools and positioning the analytical tools so that the analytical tool at an end of the stack faces the take-out opening; and wherein the case and the cover are structured as an analytical tool cartridge.

Description:

TECHNICAL FIELD

The present invention relates to a case unit for storing an analytical tool for analyzing a sample such as blood or urine or other articles in hygienic conditions.

BACKGROUND ART

FIGS. 8A, 8B, 9A and 9B show examples of conventional case unit for storing an analytical tool (see FIGS. 2A-2C, 3A-3C, 14A and 14B of International Publication WO2006/046701).

The case unit 9A shown in FIG. 8A includes a case 90 for storing an analytical tool. The case 90 has a front surface formed with a take-out opening 91. A cover 93, which is in threading engagement with a screw shaft 92, is mounted to the case 90. The cover 93 is movable in the axial direction of the screw shaft 92 by rotating around the screw shaft 92. The cover 93 includes a sealing portion (not shown) made of an elastic material. As shown in FIG. 8B, when the sealing portion faces the take-out opening 91 as a result of the rotation of the cover 93 in the arrow N10 direction, the take-out opening 91 is closed. In this state, the interior of the case 90 is hermetically closed, so that moisture or dust is prevented from entering the case 90.

The case unit 9B shown in FIG. 9A includes a case 94 for storing a plurality of analytical tools 99. The case 94 is open at the upper end. A cover 95 including a head 95a in the form of a cap is mounted to the case 94. The cover 95 further includes a cylindrical portion 95b which is slidable vertically by rotating relative to the case 94. The cylindrical portion 95b is formed with a take-out opening 96. When the cylindrical portion 95b is moved downward, the take-out opening 96 enters the case 94 to be closed. In this state, the upper opening of the case 94 is closed with the head 95a, as shown in FIG. 9B. Thus, the interior of the case 94 is hermetically closed, so that moisture or dust is prevented from entering the case 94.

However, the above-described conventional structures have the following drawbacks.

In the case unit 9A, when the sealing portion of the cover 93 is positioned to face the take-out opening 91, the sealing portion needs to be pressed strongly against the front surface of the case 90 to reliably provide hermetic sealing of the case 90. However, for the smooth rotation of the cover 93, it is desirable that the sealing portion of the cover 93 is not strongly pressed against the front surface of the case 90 when the sealing portion does not face the take-out opening 91. The cover 93 is in threading engagement with the screw shaft 92 and moves forward or rearward by the distance corresponding to the angle of rotation when it is rotated. Thus, it is difficult to set the cover 93 in such a manner that the sealing portion is to be strongly pressed against the front surface of the case 90 only when the sealing portion faces the take-out opening 91 as a result of the rotation of the cover through a predetermined angle and properly maintain the setting for a long period of time. Further, when the sealing portion is worn out, the sealing performance deteriorates.

In the case unit 9B, on the other hand, the inner diameter of the cylindrical portion 95b of the cover 95 needs to be made larger than the length or width of the analytical tool 99. Further, since the case 94 needs to accommodate the cylindrical portion 95b of the cover 95 slidably and rotatably, the case 94 also needs to be made large correspondingly to the cover 95. Thus, the case unit 9B is not suitable for reduction in size and weight.

DISCLOSURE OF THE INVENTION

An object of the present invention is to provide a case unit which is capable of reducing or alleviating the problems described above.

According to the present invention, there is provided a case unit comprising a case for storing an article which includes a front surface formed with a take-out opening through which the article is to be taken out of the case, a cover including a sealing portion for closing the take-out opening, and guiding means for enabling the cover to slide relative to the case so that the sealing portion moves reciprocally in a first and a second directions along the front surface. When the sealing portion is moved in the first direction from a position spaced from the take-out opening to a position in front of the take-out opening, the guiding means displaces the sealing portion toward the front surface so that the sealing portion is pressed against a periphery of the take-out opening.

The orientation and posture of the case of the case unit may be varied in many ways. In the present invention, the front and the rear of the case are determined based on the surface formed with the take-out opening. Thus, when the case has a plurality of surfaces, the surface region formed with the take-out opening is the front surface of the present invention regardless of in which directions the surfaces are oriented.

Preferably, the periphery of the take-out opening is formed as a tapered surface which is inclined to project forward from the front surface in such a manner that the projecting amount increases as proceeding in the first direction. In closing the take-out opening, the sealing portion is pressed against the tapered surface.

Preferably, when the sealing portion is spaced from the take-out opening, the guiding means keeps the surface of the sealing portion inclined with respect to the front surface. When the sealing portion is moved to a position in front of the take-out opening to close the take-out opening, the guiding means rotates the cover so that the surface of the sealing portion becomes parallel with the periphery of the take-out opening.

Preferably, when the sealing portion is spaced from the take-out opening, the guiding means keeps the surface of the sealing portion inclined at an angle of inclination which is larger than the angle of inclination of the tapered surface. When the sealing portion is moved to a position in front of the take-out opening to close the take-out opening, the guiding means rotates the cover so that the surface of the sealing portion becomes parallel with the tapered surface.

Preferably, the guiding means includes a guide groove provided at one of the case and the cover, and a guide projection provided at the other one of the case and the cover and received in the guide groove. The movement path of the guide projection is defined by the guide groove.

Preferably, the case includes a pair of side surfaces at each of which the guide groove is formed, whereas the cover includes a pair of side walls which face the paired side surfaces and at each of which the guide projection is formed. The guide groove includes a front inner wall and a rear inner wall facing each other and extending in the first and the second directions. The front inner wall is formed with a projecting wall portion projecting toward the rear end of the case. When the sealing portion is moved to a position in front of the take-out opening, the guide projection is guided toward the rear end of the case by the projecting wall portion so that the sealing portion is pressed against the periphery of the take-out opening and maintains the pressed state.

Preferably, the guide projection extends in the longitudinal direction of the guide groove. When the sealing portion moves while being spaced from the take-out opening, at least longitudinally opposite ends of the guide projection are held in contact with one of the front inner wall and the rear inner wall, whereas a longitudinally intermediate portion of guide projection is held in contact with the other one of the front inner wall and the rear inner wall, so that posture of the cover is substantially maintained.

Preferably, the projecting wall portion is provided at a position spaced from the take-out opening in the first and the second directions. When the guide projection is guided by the projecting wall portion to be displaced toward the rear end of the case, the cover rotates so that the sealing portion is pressed against the periphery of the take-out opening.

Preferably, the article to be stored in the case is an analytical tool used for analyzing a sample. The case unit further comprises positioning means provided in the case for supporting a plurality of analytical tools stacked in a thickness direction of the tools and positioning the analytical tools so that the analytical tool at an end of the stack faces the take-out opening. The case and the cover are structured as an analytical tool cartridge.

Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an example of case unit according to the present invention;

FIG. 2 is an exploded perspective view of the case unit shown in FIG. 1;

FIG. 3 is a sectional view taken along lines III-III in FIG. 1;

FIG. 4 is a sectional view taken along lines IV-IV in FIG. 3, showing the internal structure of the case 1 with partial omission;

FIG. 5A and FIG. 5B are sectional views showing the sliding operation of the cover of the case unit shown in FIG. 1;

FIG. 6 is a sectional view showing the case unit of FIG. 1 in the state in which the take-out opening is closed;

FIG. 7A is a cross sectional view showing another example of case unit according to the present invention, FIG. 7B is a longitudinal sectional view of the case unit, and FIG. 7C is a longitudinal sectional view of the case unit shown in FIG. 7B in the state in which the take-out opening is closed;

FIG. 8A and FIG. 8B are perspective views showing an example of conventional structure; and

FIG. 9A and FIG. 9B show another example of conventional structure.

BEST MODE FOR CARRYING OUT THE INVENTION

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIGS. 1-6 show an example of case unit according to the present invention. As shown in FIGS. 1 and 2, the case unit C1 of this embodiment includes a case 1 including a front surface 11 formed with a take-out opening 19, and a cover 2. The cover 2 is slidable along the case 1 in the vertical direction indicated by the arrows D1 and D2. The downward direction D1 is an example of first direction of the present invention. The upward direction D2 is an example of second direction of the present invention.

The case unit C1 is designed to be used in combination with e.g. an analytical apparatus A illustrated by phantom lines in FIG. 1. The analytical apparatus A is designed to perform measurement of blood glucose level in blood or other kinds of analysis when an analytical tool 8, which will be described later, is inserted into a predetermined portion of the analytical apparatus A and blood is applied to the analytical tool 8. The case unit C1 stores a plurality of analytical tools 8 to be used for such analysis (see FIGS. 3 and 6).

The case 1 may be made of a relatively hard synthetic resin. As shown in FIG. 2, the case 1 includes a main portion 10 which is generally in the form of a prism extending in the vertical direction and an auxiliary portion 14 extending forward from a lower part of the main portion 10. The main portion 10 includes the front surface 11, a rear surface 13 and a pair of side surfaces 12. As shown in FIG. 3, the case 1 is provided by combining a front case member 15A which is open at the rear end and a rear case member 15B which is open at the front end together so that a space 16 for storing articles is defined in these members. To put analytical tools 8 into the space 16, the front case member 15A and the rear case member 15B are separated from each other.

A support 17 is provided in the case 1. The support 17 supports a plurality of analytical tools 8 stacked in the vertical direction and placed on the support 17. A pushing member 41 is also provided in the case 1. The pushing member 41 pushes the top of the analytical tools 8 downward by utilizing the resilient force of a spring 40. The support 17 is so positioned that the lowermost one of the plurality of analytical tools 8 faces the take-out opening 19. Thus, the analytical tools 8 are taken out of the case 1 through the take-out opening 19 one by one from the lowermost one. For instance, as indicated by phantom lines in FIG. 1, the analytical tools 8 are taken out of the case 1 utilizing a pair of arms 70 of the analytical apparatus A. Each of the arms 70 has a hook-shaped end. The take-out opening 19 has a shape which allows the insertion of the end of each arm 70 into the case 1. Each analytical tool 8 is formed with a cutout. When the arms 70 are inserted into the case 1 through the take-out opening 19, the arms 70 engage the cutout. Thus, the analytical tool 8 is taken out of the case 1 through the take-out opening 19 while being held by the arms 70. The lower portion within the case 1 is utilized for accommodating a desiccant 89. The analytical tool 8 may be provided with a reagent for causing reaction of a sample. The desiccant 89 prevents the quality of the reagent from deteriorating due to moisture.

Of the front surface 11 of the case 1, the periphery of the take-out opening 19 is formed as a tapered surface 18 against which the sealing portion 21 of the cover 2, which will be described later, is to be pressed. The tapered surface 18 is inclined to project forward from the front surface 11 in such a manner that the projecting amount increases as proceeding in the downward direction D1. For instance, the tapered surface 18 is in the form of a rectangular loop surrounding the entire periphery of the take-out opening 19.

The cover 2 includes a frame 20 made of a synthetic resin and the sealing portion 21 for closing the take-out opening 19. The frame 20 includes a tubular portion 22 slidably fitted around the main portion 10 of the case 1. The sealing portion 21 comprises a block 21A made of e.g. synthetic rubber or other elastic materials and held by the frame 20. The sealing portion 21 is arranged to face the front surface 11 of the case 1. As shown in FIG. 3, the block 21A may be formed with a slit 210 for increasing elastic deformation.

The frame 20 is provided with an extension 23 extending forward from the case 1. As shown in FIG. 1, the extension 23 includes projections 23a. When the analytical apparatus A is moved toward the front surface 11 of the case 1, the projections 23a are fitted into guide grooves 72 formed at the upper surface of the analytical apparatus A. By this fitting, the analytical apparatus A and the case unit C1 are properly positioned relative to each other so that the paired arms 70 are properly inserted into a predetermined portion of the take-out opening 19. The auxiliary portion 14 of the case 1 is formed with guide grooves 14a extending in the front-rear direction. The guide grooves 14a are to be fitted to positioning guide portions (not shown) formed at the lower portion of the analytical apparatus A and helps the precise positioning of the analytical apparatus A and the case unit C1.

As shown in FIGS. 2 and 4, each of the side surfaces 12 of the case 1 is formed with a guide groove 30. Each of the side walls 22a of the cover 2 is formed with a guide projection 31 to be received in the guide groove 30. The combination of the guide groove 30 and the guide projection 31 is an example of guiding means of the present invention.

As shown in FIGS. 5A and 5B, each of the guide grooves 30 is provided by forming two projecting ribs 32a on the side surface 12 of the case 1. The front inner wall 30a and the rear inner wall 30b, which define the guide groove 30, extend generally in parallel with each other and linearly in the vertical direction D1, D2. At a lower portion of the front inner wall 30a, a projecting wall portion 30a′ is provided which projects toward the rear end of the case 1 (toward the rear surface 13 in this embodiment). The rear inner wall 30b is formed with a recess 30b′ at a longitudinally intermediate portion. The recess 30b′ is formed to avoid interference with a bulging portion 31b, which will be described later.

Each of the guide projections 31 has a thin elongated form extending in the same direction as the guide groove 30. The upper end 31a of the guide projection 31 has a width Wa which is substantially equal to the width of the guide groove 30. The lower end 31c of the guide projection 31 has a width Wc which is smaller than the width of the guide groove 30. With this arrangement, as shown in FIG. 5B, the lower end 31c can be inserted into a narrow portion at the lower end of the guide groove 30 behind the projecting wall portion 30a′. At a longitudinally intermediate portion of the guide projection 31, a bugling portion 31b is provided which bulges toward the rear end of the case 1. As shown in FIG. 5A, when the sealing portion 21 is spaced from the take-out opening 19, the bulging portion 31b is held in contact with the rear inner wall 30b, and the front surface of the guide projection 31 is held in surface contact with the front inner wall 30a substantially throughout the length. In this state, the guide projection 31 is slidable in the vertical direction D1, D2 while maintaining the posture. In this state, the angle of the surface 21a of the sealing portion 21 is also maintained constant. As another means for maintaining the posture of the guide projection 31, two bulging portions which bulge toward the front end of the case 1 may be provided at the upper end 31a and the lower end 31c of the guide projection 31. In this instance, the two bulging portions are held in contact with the front inner wall 30a, whereas the bulging portion 31b is held in contact with the rear inner wall 30b, whereby three-point contact is achieved.

When the sealing portion 21 is spaced from the take-out opening 19, the surface 21a of the sealing portion 21 is inclined at a predetermined angle α1 with respect to the flat surface region of the front surface 11 except the tapered surface 18. The direction of inclination of the surface 21a is the same as that of the tapered surface 18. The angle of inclination α1 of the surface 21a and the angle of inclination α2 of the tapered surface 18 are set to satisfy the relationship α12.

As shown in FIG. 5B, when the sealing portion 21 is moved to face the take-out opening 19, the lower end 31c of the guide projection 31 comes into contact with the projecting wall portion 30a′ and is displaced toward the rear end of the case 1. As a result, the sealing portion 21 is displaced toward the front surface 11 to be pressed against the tapered surface 18. Herein, the contact between the projecting wall portion 30a′ and the lower end 31c is made at a position lower than the take-out opening 19. Further, when the lower end 31c is displaced toward the rear end of the case 1, the cover 2 rotates in the direction indicated by the arrow N1. Due to this rotation, the surface 21a of the sealing portion 21 becomes parallel with the tapered surface 18.

The operation and advantages of the case unit C1 will be described below.

To take an analytical tool 8 out of the case 1, the cover 2 is moved upward so that the sealing portion 21 is positioned higher than the take-out opening 19. By this operation, the take-out opening 19 is opened. In this state, the analytical tool 8 is taken out in the manner as described before.

To close the take-out opening 19 after the analytical tool 8 is taken out, the cover 2 is moved downward so that the sealing portion 21 is positioned in front of the take-out opening 19. As described with reference to FIG. 5A, when the cover 2 moves downward, the guide projections 31 slide within the guide grooves 30 while maintaining the posture, and the surface 21a of the sealing portion 21 is kept inclined at a predetermined angle α1 with respect to the front surface 11. Therefore, even when the surface 21a comes into sliding contact with the front surface 11, the entirety of the surface 21a does not come into contact with the front surface 11, and only part of the surface 21a comes into contact with the front surface 11. Thus, the resistance generated during the reciprocal movement of the cover 2 reduces. Further, since the surface 21a maintains the same posture during the movement, the degree of contact between the surface 21a and the front surface 11 does not vary largely. For these reasons, the cover 2 moves smoothly even by the application of a small force, whereby the usability is enhanced.

As described with reference to FIG. 5B, when the cover 2 is moved downward so that the sealing portion 21 faces the take-out opening 19, the lower end 31c of the guide projection 31 is guided toward the rear end of the case 1 by coming into contact with the projecting wall portion 30a′ of the guide groove 30. As a result, the sealing portion 21 is displaced toward the front surface 11 to be pressed against the tapered surface 18. Thus, the sealing portion 21 properly closes the take-out opening 19 (see also FIG. 6). With this arrangement, since the sealing portion 21 is displaced toward the take-out opening 19 when moved to face the take-out opening 19, the sealing portion 21 is reliably pressed against the periphery of the take-out opening 19 even when it is slightly worn. Moreover, in this embodiment, the sealing portion 21 is pressed against the tapered surface 18. Therefore, as compared with a structure which does not include a tapered surface, the sealing portion 21 is strongly pressed against the periphery of the take-out opening 19 even when the amount of displacement 21 is small. Thus, the sealing portion 21 provides reliable hermetic sealing.

In this embodiment, as described with reference to FIG. 5B, in closing the take-out opening 19, the cover 2 rotates in the direction indicated by the arrow N1 so that the surface 21a of the sealing portion 21 becomes parallel with the tapered surface 18. The sealing portion 21 is pressed against the tapered surface 18 by utilizing the rotation. With this arrangement, it is not necessary to strongly press the sealing portion 21 against the tapered surface 18 in moving the sealing portion 21 to face the tapered surface 18. This also enhances the usability.

Since the lower end 31c of the guide projection 31 engages the projecting wall portion 30a′ and is held behind the projecting wall portion 30a′, the closed state of the take-out opening 19 is properly maintained. Particularly, in this embodiment, the lower end 31c of the guide projection 31 is inserted and held in the narrow portion at the lower end of the guide groove 30, as shown in FIG. 5B. With this arrangement, the closed state of the take-out opening 19 is maintained further reliably.

Analytical tools 8 need to be maintained in hygienic conditions, and particularly, need to be stored in moisture-proof and dust-proof conditions. As will be understood from the above, the case unit C1 reliably provides such conditions, and hence, is suitable for storing the analytical tools 8. Sometimes it may be necessary to carry analytical tools 8 e.g. on a trip along with the analytical apparatus A. The case unit C1 comprises the case 1 and the cover 2 slidably fitted around the case 1. The case 1 itself does not need to be made so large. As for the cover 2, it is only necessary to make the cover 2 to be slidable along the case 1, so that the thickness of each part can be made small. Thus, the case unit C1 can be reduced in size and weight, which is suitable for carrying.

FIGS. 7A-7C show another embodiment of the present invention. In these figures, the elements which are identical or similar to those of the foregoing embodiment are designated by the same reference signs as those used for the foregoing embodiment.

In the case unit C2 shown in FIGS. 7A-7C, a vertically extending guide groove 30A is provided at the rear surface 13 of the case 1. A projecting wall portion 39 projecting toward the rear end of the case 1 is provided at a lower portion of the guide groove 30A. The cover 2 has a rear wall 22a formed with at least one guide projection 31A which is to be received in and move along the guide groove 30A. As shown in FIG. 7C, when the sealing portion is moved to face the take-out opening 19, the guide projection 31A is guided toward the rear end of the case 1 by the projecting wall portion 39. As a result, the sealing portion 21 is pressed against the tapered surface 18.

In this embodiment again, due to the combination of the guide groove 30A and the guide projection 31A, the sealing portion 21 is pressed against the periphery of the take-out opening 19 in closing the take-out opening 19 and is prevented from strongly engaging the front surface 11 in other situations. Thus, the opening and closing of the take-out opening 19 is performed smoothly and easily, while ensuring hermetic sealing.

As will be understood from this embodiment, when the guiding means of the present invention comprises a guide groove and a guide projection, the guide groove and the guide projection can be provided at portions other than the side surface of the case and the side wall of the cover. Moreover, it is only necessary that the case is provided with one of the guide groove and the guide projection, whereas the cover is provided with the other one of the guide groove and the guide projection. Thus, unlike the foregoing embodiments, the cover may be provided with the guide groove, whereas the case may be provided with the guide projection. The guide projection does not necessarily need to be elongate in the longitudinal direction of the guide groove. For instance, the guide projection may be a columnar projection.

The present invention is not limited to the foregoing embodiments. The specific structure of each part of the case unit according to the present invention may be varied in design in many ways.

The guiding means of the present invention is not limited to the combination of a guide groove and a guide projection. For instance, a cam mechanism of a type which is different from the combination of a groove and a projection may be employed as the guiding means. As for the case, it is only necessary that the case includes a wall (front surface) formed with a take-out opening, and the shape and the size may be varied. The case may store articles other than analytical tools. In the present invention, the concept of the articles which can be stored in the case includes liquid or other substances which do not have a fixed shape. Since the present invention ensures hermetic sealing of the take-out opening of the case, the case unit of the present invention is also suitable for storing liquid or other flowable substances without leakage. The shape and material of the cover are not limited. Although it is preferable to make the sealing portion of the cover using an elastic material, the material is not limited to a specific one.