EP0657121A1 - Case comprising identical half-shells - Google Patents

Abstract

The case according to the invention is formed from two identical half-shells with edges (4) which can be snap-fastened over each other. Each half-shell (1) comprises a closing-off peripheral edge (4) equipped with at least two tenons (5, 6) with a rebate (rabbet) (13, 14), which are diametrically opposed and extend the edge (4). Two half-mortices (7, 8) are hollowed out in the diametrically opposed parts of the edge between the successive tenons (5, 6). It is thus possible to produce two identical half-shells. <IMAGE>

Description

The present invention relates to molded plastic housings consisting of two half-shells assembled to each other according to a snap-on rim.

The boxes usually used, for example for the protection of electronic circuits, the holding of badges, coins or other pieces of information, comprise a hollow box body closed by a snap-on cover. Examples of such boxes are described in documents US-A-4,915,214, US-A-3,100,567, US-A-4,141,400.

The production of such a case requires two molds, one for the case body, the other for the cover, the shape of which differs from that of the case body. The use of two molds significantly increases the cost of production of such a housing.

Document FR-A-2 620 257 also discloses a slot housing for the protection of an information carrier card. The housing is formed by bonding or force engagement of two identical half-shells, the engaging surfaces of which include a tenon and a mortise opposite one another with respect to the median axis of penetration of the card. Such a structure requires a significant thickness of the side walls of the housing, and does not allow relative engagement of the tenons and mortises over a significant depth. In addition, this structure does not allow snap-fastening, and the size of a mortise is too small for it to be possible to economically produce by molding removable internal snap-fastening means.

A first problem proposed by the present invention is to design an economical housing formed of two identical molded half-shells, each comprising a flange with improved engagement means cooperating over an increased height with the engagement means of the flange of the other. half-shell, the engagement means ensuring both self-centering and locking in rotation of the half-shells one on the other, the side walls of the housing being able to have a reduced thickness.

A second problem proposed by the invention is to design such engagement means further allowing the adaptation of latching means produced by molding and allowing disassembly.

The invention further aims to provide means for fixing a ring for attaching the housing. The fixing means must not protrude from the periphery of the housing, and must not require the opening of the ring for attachment to the housing.

• les deux demi-coques sont identiques,
• chaque demi-coque comprend un rebord périphérique d'obturation muni d'au moins deux tenons à feuillures, les tenons étant diamétralement opposés l'un à l'autre par rapport au centre et prolongeant le rebord de la demi-coque, chaque demi-coque comprenant en outre au moins deux demi-mortaises creusées dans des parties diamétralement opposées de rebord entre deux tenons successifs, les tenons d'une première demi-coque étant conformés et disposés pour se loger à faible jeu dans les demi-mortaises de la seconde demi-coque, les chants latéraux des tenons de la première demi-coque venant en appui contre les flancs latéraux de la demi-mortaise correspondante de seconde demi-coque.

To achieve these and other objects, a housing according to the invention is formed of first and second half-shells with flanges adapted to engage one on the other, such as:

• the two half-shells are identical,
• each half-shell comprises a peripheral sealing rim provided with at least two rebate tenons, the tenons being diametrically opposite one another with respect to the center and extending the rim of the half-shell, each half shell further comprising at least two half-mortises hollowed out in diametrically opposite portions of rim between two successive tenons, the tenons of a first half-shell being shaped and arranged to be housed with little play in the half-mortises of the second half-shell, the lateral edges of the tenons of the first half-shell coming to bear against the lateral flanks of the corresponding half-mortise of the second half-shell.

We can take advantage of the fact that the rebate tenons and the half-mortises have contact faces facing one another which are easily accessible during molding, so that latching means can be produced by molding on these contact faces. The flexibility of the tenons and half mortises allows disassembly.

Preferably, the rebates of the tenons are oriented towards the outside of the periphery of the half-shell, the half-mortises being hollowed out on the internal face of the rim. This arrangement promotes precise execution of latching means, allowing reliable latching.

In the presence of latching means, it may be advantageous to provide a half-mortise whose wall has a thickness less than or equal to half the total thickness of the corresponding side wall of half-shell. This facilitates the demolding of the half-shell during its manufacture, and improves the reproducibility of the shape of the latching element of the half-mortise, by using inexpensive molds.

To make means for attaching a ring, the studs occupy less than half the perimeter of the flange. Between a tenon and an adjacent half-mortise, the wall of the rim is deformed to constitute an external housing provided with a half-column generally parallel to the wall of the rim and intended to be assembled axially with a half-column. corresponding to the other half-shell to form a bail for hooking the ring.

• la figure 1 illustre en perspective une demi-coque à périmètre circulaire selon un mode de réalisation de l'invention ;
• la figure 2 illustre en perspective une demi-coque à périmètre carré selon un second mode de réalisation de l'invention ;
• la figure 3 est une vue en perspective montrant le détail de réalisation d'un moyen d'accrochage d'anneau selon l'invention ;
• la figure 4 est une coupe longitudinale des moyens d'accrochage d'un anneau de la figure 3 ; et
• la figure 5 est une coupe longitudinale d'un boîtier selon l'invention dans le mode de réalisation de la figure 2.

Other objects, characteristics and advantages of the present invention will emerge from the following description of particular embodiments, given in relation to the attached figures, among which:

• Figure 1 illustrates in perspective a half-shell with circular perimeter according to an embodiment of the invention;
• FIG. 2 illustrates in perspective a half-shell with a square perimeter according to a second embodiment of the invention;
• Figure 3 is a perspective view showing the detail of embodiment of a ring attachment means according to the invention;
• Figure 4 is a longitudinal section of the attachment means of a ring of Figure 3; and
• FIG. 5 is a longitudinal section of a box according to the invention in the embodiment of FIG. 2.

As shown in the figures, a housing according to the invention is formed by two identical half-shells such as the half-shells 1 and 2 illustrated in FIG. 5. Each half-shell such as the half-shell 1 comprises a main wall 3 is connected to a peripheral rim 4. For example, the main wall 3 is generally flat, and the peripheral rim 4 is generally perpendicular to the main wall surface 3.

The half-shell 1 illustrated in FIG. 1 comprises a peripheral flange 4 for obturation provided with two rebated tenons 5 and 6 respectively. The tenons 5 and 6 are diametrically opposite one another with respect to the center of the shell, and they extend the rim 4 opposite the main wall 3. The peripheral sealing rim 4 further comprises two half mortises 7 and 8 hollowed out in diametrically opposite parts of the rim 4 between the two studs 5 and 6. The pins 5 and 6 are shaped and arranged so that they can be accommodated with little play in the half-mortises 7 and 8 of another identical half-shell. In the assembly position, as illustrated in FIG. 5, the lateral edges 9 and 10 of each tenon such as the tenon come to bear against the lateral flanks 11 and 12 of the corresponding half-mortise of the other half-shell , to ensure the locking in rotation of the two half-shells relative to each other.

As illustrated in the figures, the respective rebates 13 and 14 of the tenons 5 and 6 are oriented towards the outside of the periphery of the half-shell, and the half-mortises 7 and 8 are hollowed out on the inner face of the flange 4. L The advantage is that, when the case is closed, the tenons and half mortises are invisible from the outside.

In the embodiment shown in the figures, the tenons 5 and 6 occupy less than half the perimeter of the rim 4. The same is true of the half mortises 7 and 8.

Between a tenon, such as the tenon 5 in FIG. 2 or the tenon 6 in FIG. 1, and an adjacent half-mortise such as the half-mortise 8, the wall of the rim 4 is deformed to constitute an external housing 15, for example a housing with a cylindrical wall, provided with an outer half-column 16 generally parallel to the wall of the rim 4. As illustrated in FIG. 4, the half-column 16 is intended to be assembled axially with a half-column corresponding to the other half-shell, to form a bail on which can hang a ring such as the ring 17. It suffices to pass the ring 17 around a half-column 16, before assembling the two half -shells (Figure 3). After assembly (Figure 4), the ring 17 is secured to the housing, thanks to the continuity of the two half-columns 16 which join axially by their free end and which are integral at their base with the respective half-shells 1 and 2 .

To respect the identity of the two half-shells 1 and 2, each half-shell comprises at least two half-columns diametrically opposite with respect to the center of the half-shell, and two corresponding external housings: thus, in FIG. 1, there is a second external housing 18 and a second half-column 19, diametrically opposite respectively to the first external housing 15 and to the first half-column 16.

Preferably, as illustrated in FIG. 4, one of the half-columns 16 comprises a central tenon 20, which engages in a corresponding central mortise of the other half-column 19 of another half-shell.

In the embodiment of Figure 1, the housing has a generally circular periphery. In this case, an even number of tenons and an even number of half mortises can be provided.

In the embodiment of Figure 2, the housing has a square outline, with two pins 5 and 6 in the central position on two opposite sides, and two half mortises 7 and 8 in the central position on the other opposite sides.

Alternatively, one can provide two successive tenons for each of the two opposite sides, and two corresponding half-mortises for each of the other two opposite sides.

According to another embodiment, the housing can have a polygonal contour whose number of sides is a multiple of four. At least one tenon is then provided on one side out of two, alternating with half-mortises provided on the sides connecting two sides provided with tenons.

In all the embodiments, it is advantageous to provide snap-fastening means on the respective contact faces of the tenons and half-mortises. Thus, in the embodiments shown in the figures, the tenons comprise, on their outer face, snap-fitting ribs or grooves 22, cooperating with corresponding snap-fitting grooves or ribs 23 on the inner faces of the corresponding half-mortises.

Preferably, snap ribs 23 are provided on the inside faces of the half mortises, and snap grooves 22 are provided on the outside faces of the studs. In the advantageous embodiment shown in the figures, in particular in Figure 5, the snap grooves and ribs 22 and 23 have a linear longitudinal profile and a transverse trapezoidal profile. This improves the latching behavior, and reduces the wear resulting from successive latching and dismantling operations.

The presence of tenons and half-mortises makes it possible to provide, in the mold used for making the half-shells, a series of ejectors distributed around the periphery and bearing exclusively on the end edges of the tenons and on the bottom flanges half mortises. The ejection traces, placed exclusively on the end edges of the tenons and on the bottom edges of the half-mortises, are thus invisible when the case is closed, and any trace of ejection on the main walls 3 of the housing, allowing for example an embodiment of transparent material.

According to a particular embodiment, there are also provided breakable shims, such as the shim 21 illustrated in FIGS. 1 or 2. The breakable shims allow a plate inserted in the housing to be held between the two half-shells. The breakable shims of one of the half-shells are then removed, so that the plate bears against the main wall of the first half-shell, and comes to bear on the ends of the breakable shims of the second half-shell. Thus, the breakable shims 21 can advantageously protrude from the internal face of the main wall 3 of the half-shells.

For the assembly of two half-shells, the half-shells are oriented so that the pins 5 and 6 of a first half-shell are inserted into the half-mortises 7 and 8 of the other half-shell , and we match the half-columns such as the half-column 16.

The present invention is not limited to the embodiments which have been explicitly described, but it includes the various variants and generalizations thereof contained in the field of claims below.

Claims (10)

1 - Housing formed of first and second half-shells (1, 2) with flanges (4) adapted to engage one on the other, characterized in that: - the two half-shells (1, 2) are identical, - Each half-shell (1) comprises a peripheral sealing rim (4) provided with at least two studs (5, 6) with rebates (13, 14), diametrically opposite one another with respect to the center and extending the rim (4), and at least two half-mortises (7, 8) dug in diametrically opposite parts of rim (4) of half-shell between two successive tenons (5, 6), the tenons (5 , 6) of a first half-shell (1) being shaped and arranged to be housed with little play in the half-mortises (7, 8) of the second half-shell, the lateral edges (9, 10) of the tenons (5, 6) of the first half-shell coming to bear against the lateral flanks (11, 12) of the corresponding half-mortise of the second half-shell. 2 - Housing according to claim 1, characterized in that latching means (22, 23) are made by molding on the corresponding contact faces of the pins (5, 6) and half mortises (7, 8). 3 - Housing according to one of claims 1 or 2, characterized in that the rebates (13, 14) of the pins (5, 6) are oriented towards the outside of the periphery of the half-shell, the half-mortises ( 7, 8) being hollowed out on the inner face of the rim (4). 4 - Box according to claim 3, characterized in that the half-mortises (7, 8) have a wall thickness less than or equal to half the total thickness of the corresponding side wall of the half-shell, and in that snap ribs (23) are provided on the inside faces of the half mortises (7, 8) and snap grooves (22) are provided on the outside faces of the studs (5, 6). 5 - Box according to any one of claims 1 to 4, characterized in that: - the pins (5, 6) occupy less than half the perimeter of the flange (4), - between a tenon (5) and an adjacent half-mortise (8), the wall of the rim (4) is deformed to constitute an external housing (15) provided with a half-column (16) generally parallel to the wall of the flange (4) and intended to be assembled axially with a corresponding half-column of the other half-shell to form a bail for hooking a ring (17). 6 - Box according to claim 5, characterized in that each half-shell (1, 2) comprises two half-columns (16, 19) diametrically opposite with respect to the center of the half-shell, a half-column (16) comprising a central tenon (20), the other half-column (19) comprising a central mortise in which the tenon (20) can be fitted. 7 - Housing according to any one of claims 1 to 6, characterized in that its periphery is substantially circular. 8 - Housing according to any one of claims 1 to 6, characterized in that it has a polygonal contour with number of sides multiple of four. 9 - Housing according to claim 8, characterized in that its flange (4) comprises a stud (5, 6) at least on one side out of two. 10 - Housing according to any one of claims 1 to 9, characterized in that it further comprises breakable shims (21) holding the inner plate, projecting from the inner face of the main wall (3).

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