Patent Grant
8418324
The present invention relates to a tongue used in a seat belt system for an automobile. More specifically, the present invention relates to a tongue and a method of manufacturing the same, the tongue having a structure including a tongue main body including a seat belt insertion hole in which to insert a seat belt; and an insertion part which projects on the tongue main body, and which is designed to be inserted in a buckle in a seat belt system, in which the surfaces of the insertion part are formed into concave and convex surfaces by being provided with multiple convex parts or concave parts.
As shown in
In addition, the general structure of the tongue 1 is that, as shown in
The tongue 1 of the above-described type is obtained as follows. First of all, a tongue material is produced by applying a punching process and a forming process to a metal plate by use of a pressing machine. Subsequently, as a surface treatment, a plating process is applied to the tongue material. Thereafter, the tongue material is covered with a molded resin. In a pressing process using a pressing machine, very small scraps, which are produced during the pressing process, and the like sometimes fall on the metal plate, so that very small bruises, although having no influence on the strength of the tongue itself, are caused in the surfaces of the tongue 1. Furthermore, while tongues 1 are transferred to an ensuing step in the manufacturing process, scratches, scratched marks and the like are sometimes caused in the surfaces of the tongues 1 as a result of mutual contacts between the tongues 1.
Very small bruises, scratches and the like having no influence on a tongue 1 do not matter as long as they are in an area covered with the molded resin 15 and thus look less conspicuous. On the contrary, if very small bruises, scratches and the like of the above-described type are found in any one surface of the insertion part 13 of the tongue 1 in the final stage after the molded resin 15 is molded, such a tongue 1 is discarded as a defective product. That is because: the scratches and the like look more conspicuous against the surface of the insertion part 13 which is solid and glazed; and the conspicuousness deteriorates the aesthetic appearance quality. The discard rate of tongues is approximately several percent to ten percent. This causes a problem of low yields. For this reason, the enhancement of the yields has been awaited for. In addition, it has been demanded that the bonding strength (connecting strength) between the tongue main body and the molded resin should be further increased in accordance with the material of the molded resin.
The present invention has been made for the purpose of solving the above-described problems. A first object of the present invention is to provide a tongue and a method of manufacturing the same, the tongue being capable of improving the aesthetic appearance quality by preventing scratches or the like from being caused in any one surface of the insertion part of the tongue.
A second object of the present invention is to provide a tongue and a method of manufacturing the same, the tongue being capable of improving a bonding strength (connecting strength) with the molded resin by increasing its surface area with multiple convex parts or concave parts.
In order to achieve the first and second objects, a first aspect of the present invention is a tongue used in a seat belt system including: a tongue main body including a belt insertion hole in which to insert a seat belt; an insertion part being capable of being inserted in a buckle in the seat belt system, including a lock hole to which a lock piece included in the buckle is capable of being locked, and projecting from the tongue main body; and multiple convex parts or multiple concave parts being included in a front surface of the insertion part, the front surface of the insertion part being formed into a concave and convex surface by the structure.
A second aspect of the present invention is a tongue used in a seat belt system including: a tongue main body including a belt insertion hole in which to insert a seat belt; an insertion part being capable of being inserted in a buckle in the seat belt system, including a lock hole to which a lock piece included in the buckle is capable of being locked, and projecting from the tongue main body; and multiple convex parts or multiple concave parts being included in a front surface of the tongue main body, the front surface of the tongue main body being formed into a concave and convex surface by the structure.
A third aspect of the present invention is a tongue used in a seat belt system including: a tongue main body including a belt insertion hole in which to insert a seat belt; an insertion part being capable of being inserted in a buckle in the seat belt system, including a lock hole to which a lock piece included in the buckle is capable of being locked, and projecting from the tongue main body; and multiple convex parts or multiple concave parts being included in a front surface of the insertion part and a front surface of the tongue main body, the front surface of the insertion part and the front surface of the tongue main body being each formed into a concave and convex surface by the structure.
A fourth aspect of the present invention dependent on any one of the first to third aspects is, in the tongue used in the seat belt system, the convex parts or the concave parts included in a rear surface of the tongue are formed corresponding to the convex parts or the concave parts included in the front surface.
A fifth aspect of the present invention dependent on any one of the first to fourth aspects is, in the tongue used in the seat belt system, a height of each convex part from a reference position or a depth of each concave part from the reference position is 0.01 mm to 0.10 mm.
A sixth aspect of the present invention is a method of manufacturing a tongue which is used in a seat belt system, the method including the steps of: forming a shape in which an insertion part capable of being inserted in a buckle in the seat belt system is provided in a projecting manner on a tongue main body including a seat belt insertion hole in which to insert a seat belt; performing a coining process in order to form a front surface of the insertion part into a concave and convex surface provided with multiple concave parts or multiple convex parts; applying a plating process on the tongue main body and the insertion part; and covering an area surrounding the seat belt insertion hole of the tongue main body with a resin.
A seventh aspect of the present invention is a method of manufacturing a tongue which is used in a seat belt system, the method including the steps of: forming a shape in which an insertion part capable of being inserted in a buckle in the seat belt system is provided in a projecting manner on a tongue main body including a seat belt insertion hole in which to insert a seat belt; performing a coining process in order to form a front surface of the tongue main body into a concave and convex surface provided with multiple concave parts or multiple convex parts; applying a plating process on the tongue main body and the insertion part; and covering an area surrounding the seat belt insertion hole of the tongue main body with a resin.
An eighth aspect of the present invention is a method of manufacturing a tongue which is used in a seat belt system, the method including the steps of forming a shape in which an insertion part capable of being inserted in a buckle in the seat belt system is provided in a projecting manner on a tongue main body including a seat belt insertion hole in which to insert a seat belt; performing a coining process in order to form a front surface of each of the tongue main body and the insertion part into a concave and convex surface provided with multiple concave parts or multiple convex parts; applying a plating process on the tongue main body and the insertion part; and covering an area surrounding the seat belt insertion hole of the tongue main body with a resin.
The first to eighth aspects of the present invention makes it possible to enhance the aesthetic appearance quality of the tongue by preventing scratches or the like from being caused in any one surface of the insertion part of the tongue. In addition, the first to eighth aspects of the present invention makes it possible to increase the bonding strength (connecting strength) with the molded resin by increasing the surface area with the multiple convex parts or concave parts.
a), 1(b) and 1(c) are explanatory diagrams showing an example of how to use a conventional tongue and how the conventional tongue is structured.
a), 6(b), 6(c), 6(d) and 6(e) are explanatory diagrams showing shapes of convex parts.
a) and 7(b) are cross-sectional explanatory diagrams showing shapes of concave and convex surfaces.
a), 10(b), 10(c) and 10(d) are explanatory diagrams of concave and convex surfaces formed in tongue materials.
a), 11(b) and 11(c) are explanatory diagrams of other concave and convex surfaces formed in tongue materials.
Descriptions will be hereinbelow provided for best modes for the present invention on the basis of
As shown in
A lock hole 27a, to which a lock piece included in the buckle is capable of being locked, is formed in the neighborhood of a front end portion of the insertion part 27. In addition, an area surrounding the seat belt insertion hole 23 formed in the tongue main body 25 is covered with a molded resin 31 as in the case of the conventional tongue.
Multiple convex parts 29 are formed over both the front and rear surfaces of each of the tongue main body 25 and the insertion part 27 in the tongue 21 at appropriate intervals. In other words, both the entire front and rear surfaces thereof are formed into concave and convex surfaces by the provision of the convex parts 29. The convex parts 29 are formed by a coining process during a step of applying a pressing process to the tongue 21. The convex portions 29 may be those which project in a way to be embossed on a plane part 27b of each of the front and rear surfaces of the insertion part 27.
Note that the convex parts 29 slightly project from the plane part 27b, although
Instead of the convex parts 29, concave parts may be formed in locations of the convex parts 29, respectively, as the structure in which both the front and rear surfaces of the tongue 21 are formed into the concave and convex surfaces. In other words, the structure of the concave and convex surface may be any one of the structure in which the convex parts 29 are formed on the plane part, the structure in which the concave parts are formed in the plane part, and a structure in which the convex parts 29 and the concave parts are formed in the plane part. An important point is that each concave and convex surface should not be a smooth surface.
As described above, the tongue main body 25 of the tongue 21 has the concave and convex surfaces formed by being provided with the convex parts 29. This increases the surface area of the tongue main body 25, and thus enhances the bonding (joining, adhering) strength between the tongue main body 25 and the molded resin 31 when the area surrounding the seat belt insertion hole 23 included in the tongue main body 25 is covered with the molded resin 31.
In addition, each concave and convex surface having the convex parts 29 is formed by the coining process. For this reason, even when there are very small bruises, scratches and the like in the tongue main body 25 and the insertion part 27 in a step preceding the step of forming the convex parts 29, it is possible to erase them so as to make them inconspicuous through the coining process. In addition, because the concave and convex surfaces each having the convex parts 29 are formed in the insertion part 27 of the tongue 21, it is possible to inhibit another tongue and the like from contacting or abutting on any plane part 27b of the insertion part 27. This makes it possible to inhibit scratches and the like from occurring in each plane part 27b.
Furthermore, even in a case where tongues 21 come in contact with each other and cause scratch marks or the like therein, the marks are caused in top portions of some convex parts 29, and have no influence on the strength of the tongue 21. In addition, the length of each mark is so short that the mark cannot be recognized. This makes it possible to enhance the aesthetic appearance quality of each tongue.
The shapes of, and the intervals between, the convex parts 29 formed in the tongue main body 25 and the insertion part 27 of the tongue 21 may be equal to, or different from, one another. For instance, the shapes of, and the intervals between, the convex parts 29 in the tongue main body 25 are determined by giving consideration to how a resin flows when the molded resin 31 is molded, and to the performance of intimate contact (joining, bonding) between the tongue main body 25 and the molded resin 31. Furthermore, it is desirable that the shapes of, and the intervals between, the convex parts 29 in the insertion part 27 should be determined by giving consideration to the inhibition of scratches caused by the insertion part 27 being brought into contact with the buckle in its repeated insertion to and detachment from the buckle.
In the present embodiment, the intervals at which the convex parts 29 are arranged are set smaller than the plate thickness dimension of each tongue 21 in order that, when the tongue 21 and a different tongue 21 interfere with each other, no plane part of the tongue 21 should be directly brought into contact with the different tongue 21. For this reason, even in a case where tongues 21 abut on or contact each other, it is possible to inhibit one tongue 21 from abutting on or contacting either plane part of the tongue main body 25 or either plane part 27b of the insertion part 27 in the other tongue 21. This makes it possible to prevent very small scratches and the like from being caused in any plane part.
Further, when both of the front and rear surfaces of each of the tongue main body 25 and the insertion part 27 are formed into the concave and convex surface by employing a structure of causing the convex parts 29 to project from the plane parts thereof, the projecting height of each convex part 29 is set in a range of 0.01 mm to 0.1 mm above the corresponding plane part which is the reference position. When a structure of including concave parts is employed, the depth of each concave part is set in a range of 0.01 mm to 0.1 mm under the corresponding plane part which is the reference position. When a structure of including convex parts 29 and concave parts is employed, the dimensional difference of elevation between the top portion of each convex part 29 and the bottom portion of each concave part is set in a range of 0.01 mm to 0.1 mm.
To be more specific, when the tongue main body 25 of the tongue 21 is covered with the molded resin 31 by molding with the tongue main body 25 being inserted and set between molding dies MD as shown in a partial schematic magnified cross-sectional view of
The molded resin 31 flows into a space R, which is formed by each molding die MD and the tongue main body 25, as indicated by arrows extending from the left to the right in
While the molded resin 31 is advancing in the direction indicated by the arrows, if the clearance C is too large, flashes are sometimes formed in the following manner: the molded resin 31 advances beyond the space R; the molded resin 31 leaks out of the space R, thus flowing into the clearance C. For this reason, it is desirable that the projecting height of each convex part 29, the depth of each concave part, and the like should be not more than 0.10 mm.
If the projecting height of each convex part 29, the depth of each concave part, and the like are not more than 0.01 mm, the gap (clearance) dimension between each molding die MD and the corresponding plane part of the tongue main body 25 is reduced. This deteriorates the escapability (flow-out performance) of the gas flowing out of the die when the molded resin 31 is filled in the molding die MD. For this reason, the too small projecting height of the convex part 29, the too small depth of the concave part, and the like are undesirable from a viewpoint of enhancing the productivity and the molding quality of the molded resin 31.
It is more desirable that the concave and convex surface should be formed in a way that the clearance C between each molding die MD and the corresponding plane part of the tongue main body 25 is in a range of 0.03 mm to 0.08 mm. When the clearance C is set in the above-mentioned range, it is possible to inhibit the flashes mentioned above from being formed, and concurrently to enhance the flow-out performance of the gas flowing out of the die. This makes it possible to enhance the productivity easily.
Meanwhile, the tongue 21 is beforehand subjected to a plating process when the tongue main body 25 of the tongue 21 is covered with the molded resin 31. For this reason, the tongue main body 25 has a glazed smooth surface in a state where no convex parts 29 or the like are formed (with a structure in which a solid surface is employed as in the case of the conventional usual tongue). In addition, as shown in the partial schematic magnified cross-sectional view of
For this reason, when molding is performed in order to cover a tongue main body of a conventional usual tongue with a molded resin, the molded resin tends to slip on each surface of the tongue main body of the conventional tongue, and the crimped surface S of each molding die MD works as a resistance against the flow of the molded resin 31. In other words, the flow of part of the resin 31 which contacts any one surface of the tongue main body of the conventional tongue and the flow of part of the resin 31 which contacts the crimped surface S of the corresponding molding die MD go out of balance. This is problematic from a viewpoint of enhancing the aesthetic appearance quality of the molded resin.
On the contrary, in the case of the present embodiment, the concave and convex surfaces each including the convex parts 29 and/or the like which are arranged at appropriate intervals are formed in the tongue main body 25 of the tongue 21. For this reason, when molding is performed in order to cover the part of the tongue main body 25 with the molded resin 31, each concave and convex surface provided to the tongue main body 25 works as a resistance against the flow of the molded resin. Accordingly, when the molded resin 31 is filled between the molding dies MD with the tongue main body 25 being inserted and set therebetween, it is possible to make almost equal the flow of part of the molded resin which contacts any one surface of the tongue main body 25 and the flow of part of the molded resin 31 which contacts the crimped surface S of the corresponding molding die MD. This makes it possible to inhibit the unbalance in the flow of the molded resin, and thus to solve the conventional problem described above.
As already understood, the formation of the concave and convex surface including the convex parts 29 and/or the like on both the entire front and rear surfaces of each of the tongue main body 25 and the insertion part 27 of the tongue 21 makes it possible to enhance the aesthetic appearance quality of the tongue 21, and concurrently to enhance the quality with which the molded resin 31 is molded. In addition, as another structure for making equal the flow of part of the molded resin which contacts the crimped surface of any one molding die MD and the flow of part of the molded resin 31 which contacts the corresponding surface of the tongue main body 25 of the tongue 21, as shown
Further, in the conventional tongue, for instance, a center portion of the insertion part is sometimes deformed slightly in a way to curve downward (or upward) in the middle portion in the width direction of the insertion part along the axis in the projecting direction of the insertion part due to the release of the tongue from a shearing resistance, an internal stress, and the like which occur when a blanking or piercing process is applied to the tongue during the pressing process. The insertion part is required to be flat with high precision, because the insertion part is a part configured to engage with the buckle in the seat belt system. For this reason, the above-mentioned curve is heretofore corrected in some cases.
On the contrary, in the present embodiment, the tongue 21 is formed to have the concave and convex surfaces provided with the convex parts 29 by being subject to the coining process. Thus, even if the curvature or the like occurs in the tongue 21, such curve is corrected by the coining process. Furthermore, once the multiple convex parts 29 are formed in the tongue main body 25 and the insertion part 27, the tongue becomes less likely to curve. For this reason, the tongue rarely curves again after the tongue is released from the coining die.
The tongue 21 is manufactured in almost the same manner as that of the conventional tongue. In other words, through the pressing process, the seat belt insertion hole 23 is punched out in part of a belt-shaped steel plate as a metal plate, which corresponds to the tongue main body 25, and concurrently a shape integrally including the tongue main body 25 and the insertion part 27 is punched out of the steel plate. In addition, necessary forming processes such as a trimming process are applied to an outline portion of the tongue main body 25, an outline portion of the insertion part 29, as well as outline portions respectively of the seat belt insertion hole 23 and the like as in the case of the manufacturing of the conventional tongue. Subsequently, before a plating process as a surface treatment is performed, the coining process is applied to the tongue 21 by use of a coining die. Thereby, the multiple convex portions 29 and/or the like are formed in both the front and rear surfaces of each of the tongue main body 25 and the insertion part 27, and both the front and rear surfaces thereof are thus formed into the concave and convex surfaces. Thereafter, as in the case of the conventional tongue, the molded resin 31 is molded in the area surrounding the seat belt insertion hole 23 of the tongue main body 25 with the tongue 21 being inserted and set between the molding dies.
In other words, the method of manufacturing the tongue 21 according to the present embodiment follows the method of manufacturing the convention tongue, and the two methods are almost identical to each other. The difference between the two methods is that the method of manufacturing the tongue 21 according to the present embodiment additionally includes the coining process of forming the concave and convex surface, which includes convex parts 29 and/or the like, on both the entire front and rear surfaces of the tongue 21 as a step preceding the surface treatment step such as the plating process.
Note that: the present invention is not limited to the foregoing embodiment; and the present invention can be carried out as another embodiment by modifying the present invention depending on the necessity. In other words, the entire surfaces of both the tongue main body 25 and the insertion part 27 are not necessarily formed into the concave and convex surface including the convex parts 29 and/or the like. The two surfaces of either the tongue main body 25 or the insertion part 27 may be formed into the concave and convex surface depending on the necessity. Alternatively, the concave and convex surface including the convex parts 29 and/or the like may have a structure of causing a convex part 29 which correspond to, for instance, a portion of wire lines defining holes of a wire net, to extend successively on the entire surface. In this case, one concave part is used. Furthermore, various designs can be applied to the insertion part 27 by providing convex parts 29 or concave parts to the insertion part 27. This enhances the aesthetic appearance quality.
Meanwhile, yet another structure may be selected as the structure in which both the front and rear surfaces of each of the tongue main body 25 and the insertion part 27 in the tongue 21 are formed into the concave and convex surfaces. In this structure, as shown by a magnified part of the tongue 25 of
As emphatically shown in the following drawings, the shape of each convex part 29 may be any desired shape selected, for instance, from a cone 292 as shown in
Furthermore, as a structure in which both the front and rear surfaces of the tongue 21 are formed into the concave and convex surfaces, the front and rear surfaces may be formed in a way that, as shown in
As conceptually and schematically shown in
Note that it is desirable that the foregoing configuration should include backup rolls configured to press the paired transfer rolls R1, R2 in the directions in which the paired transfer rolls R1, R2 come closer to each other, for the purpose of preventing the paired transfer rolls R1, R2 from going away from each other when the patterns of the concave and convex surfaces 33A, 33B of the transfer rolls R1, R2 are transferred to the tongue material 21B.
Otherwise, the formation of both the front and rear surfaces of the tongue 21 into the concave and convex surface may be achieved by a structure in which, as schematically and schematically shown in
When the concave and convex surfaces are formed in both the front and rear surfaces of the tongue material 21B, the density of the convex parts or the concave parts in a portion of the tongue main body 25 which is covered with the molded resin 31 may be higher (larger) than the density of the convex parts or the concave parts in the insertion part 27 by making each convex part or concave part in the portion of the tongue main body 25 which is covered with the molded resin 31 smaller in size than each convex part or concave part in the insertion part 27, as in the case of a tongue 212 according to another embodiment which is shown in
Furthermore, each concave and convex surface may be formed with a structure in which convex parts or/and concave parts are almost evenly distributed throughout each surface of the tongue material 21B, as in the case of a tongue 213 according to yet another embodiment which is shown in
Still furthermore, the tongue material 21B may be made with a structure in which a concave and convex surface including convex parts 29 or concave parts is formed, except for its portion covered with the molded resin 31, namely in its portion which is not covered with the molded resin 31, as in the case of a tongue 216 according to another embodiment which is shown in
Yet still furthermore, as a modification of the tongue shown in
c) shows a modification of the tongue shown in
In short, as understood through the foregoing descriptions, the embodiments make it possible to enhance the aesthetic appearance quality of the insertion part 27 in the tongue 21, and accordingly to solve the conventional problem described above.
The present invention is not limited to what has been described with regard to the foregoing embodiments of the present invention. In addition to the above-described mode, the present invention can be carried out as other various modes by modifying the present invention depending on the necessity.
Note that all the contents of Japanese Patent Application No. 2007-167431 (filed on Jun. 26, 2007) are incorporated herein by reference.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2007-167431 | Jun 2007 | JP | national |
| Filing Document | Filing Date | Country | Kind | 371c Date |
|---|---|---|---|---|
| PCT/JP2007/067513 | 9/7/2007 | WO | 00 | 12/21/2009 |
| Publishing Document | Publishing Date | Country | Kind |
|---|---|---|---|
| WO2009/001482 | 12/31/2008 | WO | A |
| Number | Name | Date | Kind |
|---|---|---|---|
| 3696471 | Mermelstein | Oct 1972 | A |
| 6195849 | Smith et al. | Mar 2001 | B1 |
| 20010014997 | Suzuki et al. | Aug 2001 | A1 |
| 20030106192 | Schmitz | Jun 2003 | A1 |
| 20030234530 | Moskalik et al. | Dec 2003 | A1 |
| 20060138852 | Ichida | Jun 2006 | A1 |
| Number | Date | Country |
|---|---|---|
| 54-033823 | Mar 1979 | JP |
| 03-200192 | Sep 1991 | JP |
| 09-290706 | Nov 1997 | JP |
| 10-063763 | Mar 1998 | JP |
| 2000-176664 | Jun 2000 | JP |
| 2002-096712 | Apr 2002 | JP |
| 3440063 | Aug 2003 | JP |
| 2006-182103 | Jul 2006 | JP |
| WO2006132129 | Dec 2006 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 20100180409 A1 | Jul 2010 | US |
