JP2928711B2 - Seal structure of synthetic resin case - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a seal structure for a synthetic resin case, and more particularly, to a seal structure for a synthetic resin case suitable for a case of a portable wireless device.

[0002]

2. Description of the Related Art Conventionally, a rubber packing has been used for a seal structure of a portable wireless device requiring waterproofness. That is, as shown in FIG. 5, the rubber packing is disposed between the rear case and the front case, and the rear case and the front case are joined to sandwich the rubber packing in the groove provided on the mating surface.

[0003] Examples of the shape of the groove and the shape of the rubber packing are as shown in FIG. 6 (a), in which a square packing is fitted into a groove provided in the front case, or as shown in FIG. 6 (b). In some cases, a round packing is fitted into grooves provided in both the front case and the rear case.

[0004]

In the conventional seal structure using the rubber packing described above, when the packing is thin and soft, it is difficult and time-consuming to fit it into the groove of the front case or the rear case. There was a problem.

[0005] In addition, a complicated structure having a step on the mating surface into which the packing is to be fitted makes it difficult to assemble, so the fitting structure of the case must be a simple structure. Alternatively, when a simple structure cannot be formed with one mating surface, it has been necessary to divide each necessary portion and perform waterproof treatment.

The present invention has been made in view of the above points, and an object of the present invention is to provide a seal structure for a synthetic resin case that is easy to assemble.

Another object of the present invention is to provide a sealing structure for a synthetic resin case that can seal with a single mating surface even in a complicated structure having a step at the mating surface.

[0008]

According to the present invention, there is provided a seal structure for a synthetic resin case, in which a groove or a step is provided on a mating surface of one of the two synthetic resin cases, and a case body is formed on a mating surface of the other case. A sealing member made of a resin having lower hardness is provided integrally with the case body by double molding, and when the two cases are combined, the thin portion of the sealing member extending in the side direction of the groove or the step is formed of the groove or the step. It is configured to be pressed against the side surface.

[0009]

According to the sealing structure for a synthetic resin case of the present invention, since the sealing member is integrally provided on the mating surface of the case body, the time and effort for assembling the sealing member to the case are omitted, and the number of assembling steps is reduced. . In particular, the effect is great when the sealing member is thin or when the mating surface of the case has a complicated structure.

In addition, since the thin portion of the seal member provided on the case mating surface and extending in the side direction of the groove or the step is pressed against the side surface of the groove or the step, the acting direction of the pressure for pressing the seal member is provided. Is different from the direction in which the case is fitted, so the reaction exerts a small force acting to separate the case, and even when the sealing member is relatively hard, the force for stopping the case with screws or the like is reduced, that is, the number of screws Can be reduced.

[0011]

An embodiment of the present invention will be described with reference to the drawings. FIG. 1A is a partial cross-sectional view showing a state immediately before the case is fitted in the synthetic resin case sealing structure according to the first embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes a front case, which is formed by molding with ABS resin. Reference numeral 1a denotes a seal member integrally formed with the front case 1 by double molding. In the double molding, first, the front case 1 is made by injecting a resin into a mating mold and molding, and then one of the molds is replaced to create a space between the front case 1 and the mold, and a sealing member is formed there. , And the sealing member 1a is integrally formed with the front case 1.

The material of the seal member 1a is a thermoplastic polyester elastomer, and has a hardness of about 88 in a JIS spring hardness test. Although this hardness is softer than ordinary synthetic resin, it is considerably harder than the hardness (30 to 40) of a rubber packing generally used.

The rear case 2 is made of a synthetic resin and has a groove 2a into which the seal member 1a is fitted. The seal member 1a is provided with a thin portion 1b extending in the side direction of the groove 2a.

FIG. 1B shows the front case 1 and the rear case 2.
Shows the state where. As shown in the figure, the thin portion 1b is deformed and exerts a contact pressure in the direction of F1 on the side surface of the groove 2a. This contact pressure provides a sealing effect.

The component of the contact pressure F1 in the case alignment direction is F
2, but the size is greatly reduced as compared with the contact pressure F1. Therefore, the number of screws for aligning the front case 1 and the rear case 2 can be reduced, the number of assembling steps is reduced, and the appearance is also excellent.

FIG. 2 is a partial sectional view showing a seal structure of a synthetic resin case according to a second embodiment of the present invention. In this example, a step is provided on the mating surface of the rear case 2, and the thin portion 1 b of the seal member 1 a provided integrally with the front case 1 is provided on the side surface 2 b of the step as in the first embodiment. It is pressed.

FIG. 3 is a partial sectional view showing a sealing structure of a synthetic resin case according to a reference example of the present invention. In this example, the sealing member 1 c provided integrally with the front case 1 by double molding enters the groove 2 a of the rear case 2. Seal member 1
There is a gap between the mating surfaces of the front case 1 and the rear case 2 when the tip of c contacts the bottom surface of the groove 2a, and the sealing member 1c is deformed by bringing the mating surfaces into close contact to obtain a sealing effect. I have.

Since the pressure for deforming the seal member 1c acts in the direction in which the cases are joined together, the tightening force required to overcome the reaction force increases, so that the present invention has more excellent effects. . If the seal member 1c is made of a relatively soft material, it is not necessary to increase the tightening force for aligning the cases.

In the sealing structure of the present invention, since it is not necessary to fit the rubber packing into the groove of the case mating surface, even if the mating surface has a complicated shape with a step as shown in FIG. The front and rear cases can be combined as a structure.

The embodiment is configured as described above.
The invention is not limited to this. For example, instead of attaching the seal member to the front case, a seal member may be attached to the rear case to provide a groove or a step in the front case.

[0022]

According to the sealing structure of the synthetic resin case of the present invention, the troublesome work of fitting a soft packing into the groove of the case is omitted, so that the productivity is improved and the manufacturing cost can be reduced.

Although the mold for double molding is expensive, in the case of mass production, the manufacturing cost due to the number of assembling steps has a greater effect on the overall manufacturing cost than the amortization of the mold cost. Manufacturing costs are reduced.

Further, compared with the conventional seal structure in which the packing is manually fitted into the groove, the seal member is accurately positioned by the mold, so that the waterproof effect can be reliably obtained. That is, the quality is stabilized.

Further, since the thin structure of the seal member provided on the case mating surface and extending in the side direction of the groove or the step is pressed against the side surface of the groove or the step, the acting direction of the pressure for pressing the seal member is applied. Is different from the direction in which the case is fitted, the reaction exerts a small force acting to separate the case, and even when the sealing member is relatively hard, the force for stopping the case with screws or the like can be reduced. That is, the number of screws can be reduced. Therefore, screw material costs and man-hours for tightening are reduced,
The appearance is also excellent.

[Brief description of the drawings]

FIG. 1A is a partial cross-sectional view showing a state immediately before fitting a case in a synthetic resin case sealing structure according to a first embodiment of the present invention, and FIG. FIG. 7 is a partial cross-sectional view showing a state in which

FIG. 2 is a partial sectional view showing a seal structure of a synthetic resin case according to a second embodiment of the present invention.

FIG. 3 is a partial sectional view showing a seal structure of a synthetic resin case according to a reference example of the present invention.

FIG. 4 is a perspective view showing an example of a mating surface of a case to which a seal structure of a synthetic resin case of the present invention is applied.

FIG. 5 is a perspective view showing an example of a conventional seal structure of a synthetic resin case.

FIG. 6 is a partial cross-sectional view showing an example of a conventional seal structure of a synthetic resin case.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Front case 1a Seal member 1b Thin part 1c Seal member 2 Rear case 2a Groove

Claims (1)

(57) [Claims] A groove or a step is provided on the mating surface of one of the two synthetic resin cases, and a sealing member made of a resin having a lower hardness than the case main body is formed on the mating surface of the other case by double molding. And a seal structure of a synthetic resin case in which the thin portion of the seal member extending in the side direction of the groove or the step is pressed against the side surface of the groove or the step when the two cases are combined. .