JP2005233268A - Projection welding nut made of aluminum alloy - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projection welding nut made of aluminum alloy capable of securing both the bonding strength of a weld and the thread strength of a threaded part. <P>SOLUTION: The projection welding nut 10 made of aluminum alloy is formed from the threaded part 14 consisting of 7000 series aluminum alloy material and a projection part 16 consisting of a 5000 series or 2000 series aluminum alloy material. The former has a property with high thread strength, while the latter has a property with high resistance against separation. Accordingly this allows securing both the bonding strength of the weld and the thread strength of the threaded part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an aluminum alloy projection welding nut joined to an aluminum alloy panel by projection welding.

  Conventionally, steel panel body panels have been the mainstream, but recently, body panels using light metal materials such as aluminum alloys are becoming widespread from the viewpoint of weight reduction and fuel efficiency reduction. Along with this, various improvements have been made to the projection weld nut set at the appropriate position on the body panel so that it fits the material of the body panel to be joined and satisfies the required characteristics such as joint strength and thread strength. .

  For example, in the projection welding nut disclosed in Patent Document 1 below, an aluminum alloy insert in which a wire is processed into a ring shape between the two in order to perform projection welding of an aluminum alloy nut to an aluminum alloy panel. It is designed to be resistance welded with an intervening metal.

According to the above configuration, since the contact portion between the insert and the panel and the contact portion between the insert and the nut are both in line contact, the insert performs the same function as the projection of the conventional projection welding when energized, resulting in heat generation efficiency. High resistance spot welding is possible.
JP-A-6-63759

  However, according to the above prior art, since the projection welding nut itself is made of the same kind of aluminum alloy, it is impossible to achieve both of the joint strength of the welded portion and the screw strength of the threaded portion.

  In view of the above facts, an object of the present invention is to obtain an aluminum alloy projection weld nut capable of securing both the joining strength of the welded portion and the screw strength of the threaded portion.

  The projection welding nut made of aluminum alloy according to the first aspect of the present invention is an projection projection nut made of aluminum alloy that is joined to an aluminum alloy panel by projection welding, and is a projection part that serves as a joint to the aluminum alloy panel. Is made of a first aluminum alloy material having a high peel strength, and a thread portion where a female screw is formed is made of a second aluminum alloy material having a high screw strength.

  According to a second aspect of the present invention, there is provided the projection welding nut made of an aluminum alloy according to the first aspect of the present invention, wherein the projection portion and the screw portion are formed separately from each other, and the projection is formed by caulking one to the other. The part and the screw part are integrated.

  According to a third aspect of the present invention, there is provided a projection weld nut made of an aluminum alloy according to the first aspect of the present invention. In the first aspect, the projection portion is a washer configured separately from a nut body having the screw portion, and the washer. And projection projections provided integrally on the front and back surfaces of the projection.

  The aluminum alloy projection weld nut according to claim 4 is the invention according to any one of claims 1 to 3, wherein the first aluminum alloy material is a 2000 series or 5000 series aluminum alloy material. The second aluminum alloy material is a 7000 series aluminum alloy material.

  According to the first aspect of the present invention, since the projection part to be joined to the aluminum alloy panel is formed of the first aluminum alloy material having high peel strength, one of the required characteristics for the aluminum alloy projection welding nut is provided. As a result, the bonding strength is ensured. Moreover, since the thread part in which the internal thread is formed is made of the second aluminum alloy material having high thread strength, the thread strength, which is one of the required characteristics for the aluminum alloy projection weld nut, is also ensured.

  That is, according to the present invention, since the aluminum alloy projection weld nut is configured by combining two types of aluminum alloy materials having different properties, it is possible to ensure both the joint strength and the screw strength.

  According to the second aspect of the present invention, the projection portion and the screw portion are configured separately, and the projection portion and the screw portion are integrated by caulking one to the other. The part and the screw part can be easily manufactured. Further, since the projection portion and the screw portion are also joined by caulking, it is relatively easy to ensure the joining accuracy.

  According to the third aspect of the present invention, the washer having the projection projections on the front and back surfaces is interposed between the aluminum alloy panel and the nut body, and projection welding is performed in this state. Thereby, the projection protrusion on the front surface side of the washer is melted and the washer is joined to the nut body, and the projection protrusion on the back surface side of the washer is melted to join the washer to the aluminum alloy panel.

  Thus, even if the screw portion and the projection portion are separately configured, the washer including the projection protrusion is made of the first aluminum alloy material having high peel strength, and the nut body including the screw portion has high screw strength. Since the second aluminum alloy material is used, it is possible to ensure both the joining strength and the screw strength.

  In addition, since the screw portion and the projection portion are configured separately and integrated at the time of welding, a caulking step is not necessary. Therefore, the manufacturing process of the aluminum alloy projection welding nut can be reduced.

  According to the fourth aspect of the present invention, the first aluminum alloy material is a 2000 or 5000 series aluminum alloy material, and the second aluminum alloy material is a 7000 series aluminum alloy material. The characteristics of can be utilized. That is, the 2000 series or 5000 series aluminum alloy material has a property of high peel strength, and is suitable as a constituent material of the projection part. Further, the 7000 series aluminum alloy material has a property that the screw strength is high, and is suitable as a constituent material of the screw portion. Therefore, a composite nut is constructed that takes advantage of the characteristics of each aluminum alloy material.

  As described above, the projection weld nut made of aluminum alloy according to claim 1 is configured such that the projection part to be joined to the aluminum alloy panel is made of the first aluminum alloy material having high peel strength and the female screw is formed. Since the threaded portion is made of the second aluminum alloy material having high thread strength, the advantages of the first aluminum alloy material and the second aluminum alloy material can be utilized, and as a result, the welded portion can be joined. It has an excellent effect that both the strength and the screw strength of the thread portion can be secured.

  According to a second aspect of the present invention, there is provided the projection weld nut made of an aluminum alloy according to the first aspect of the present invention. Since the projection unit and the screw unit are integrated, the projection unit and the screw unit can be easily manufactured, and the joining accuracy between the projection unit and the screw unit can be relatively easily ensured. As a result, the aluminum alloy projection weld nut according to the present invention has an excellent effect that both productivity and reliability can be improved.

  According to a third aspect of the present invention, there is provided a projection weld nut made of an aluminum alloy according to the first aspect of the present invention, wherein the washer constructed independently of the nut main body having the threaded portion and the front and rear surfaces of the washer are integrated with each other. Since the projection part is constituted by the provided projection projection, the caulking process is unnecessary, and the production process of the aluminum alloy projection welding nut can be reduced correspondingly, and as a result, the production line length can be shortened. It has excellent effects such as being able to.

  The projection welding nut made of aluminum alloy according to the present invention as set forth in claim 4 is the invention according to any one of claims 1 to 3, wherein the first aluminum alloy material is a 2000 series or 5000 series aluminum alloy material. Since the second aluminum alloy material is a 7000 series aluminum alloy material, a composite nut that takes advantage of the characteristics of each aluminum alloy material is constructed. As compared with the case of producing an aluminum alloy projection weld nut capable of obtaining the same effect as the above, there is an excellent effect that the cost can be reduced.

[First Embodiment]
A first embodiment of an aluminum alloy projection welding nut according to the present invention will be described below with reference to FIGS.

  FIG. 1 shows the overall configuration of an aluminum alloy projection welding nut 10 according to the present embodiment. As shown in this figure, the aluminum alloy projection welding nut 10 is constituted by a screw portion 14 in which a female screw 12 is formed, and a projection portion 16 disposed at the lower end portion of the screw portion 14.

  The projection portion 16 is integrally formed on the surface side of the flange portion 16A, and has a flange portion 16A formed in a substantially ring plate shape having an outer diameter larger than that of the screw portion 14 so as to be a pedestal of the screw portion 14. A plurality of caulking portions 16B formed at predetermined positions in the direction, and a plurality of protrusions 16C formed integrally at the rear surface side of the flange portion 16A and formed at predetermined positions in the circumferential direction. Among these, the plurality of projecting portions 16C are portions that function as actual projection portions when performing projection welding.

  A hexagonal column-shaped concave portion 18 into which the screw portion 14 can be attached is formed in the shaft core portion of the flange portion 16A, and the screw portion 14 is fitted into the concave portion 18. And the screw part 14 and the projection part 16 are integrated by caulking the caulking part 16B into the engaging groove 20 formed in the lower outer peripheral surface of the screw part 14.

  Here, as shown in FIGS. 2 and 3, the projection unit 16 described above is a 5000 series aluminum alloy material having a high peel strength with respect to the aluminum alloy panel 22 (see FIG. 1) (“ (Corresponding to “first aluminum alloy material”). On the other hand, as shown in FIG. 4, the screw portion 14 is made of a 7000 series aluminum alloy material (corresponding to the “second aluminum alloy material” of the present invention) having a high screw strength property. Yes. Instead of the 5000 series aluminum alloy material, a 2000 series aluminum alloy material (corresponding to the “first aluminum alloy material” of the present invention) having the same properties may be used. Further, supplementing the properties of the materials, the 5000 series and 2000 series aluminum alloy materials have high electric resistance values and are suitable for projection welding, and the 7000 series aluminum alloy materials have a high proof stress.

  Next, the operation and effect of this embodiment will be described.

  First, the characteristics of the projection welding nut 10 using 5000 series, 2000 series, and 7000 series aluminum alloy materials will be described. In addition, the test tested the joining strength and screw strength about four types of aluminum alloy materials typical as a candidate material of an aluminum alloy projection welding nut.

  FIG. 5 shows an outline of the “indentation peeling test method” defined in JIS-B1196, and FIG. 2 shows the test results. In FIG. 2, “•” is an average value of measurement values (representative measurement value of each system), and a solid line graph connects the average values. In the indentation peeling test, an aluminum alloy panel 22 having a bolt insertion hole 24 formed thereon and welded to the aluminum alloy projection welding nut 10 having the above-described configuration is set on a spacer 26, and a test machine The indentation peel strength is measured by screwing the bolt portion 30 attached to the tip end portion of 28 into the screw portion 14 of the projection welding nut 10 made of aluminum alloy and applying a downward load in this state. As can be seen from the test results of FIG. 2, the indentation peel strength shows a high value for the 2000 series and 5000 series aluminum alloy materials, and the 6000 series aluminum alloy material shows the lowest values.

  FIG. 6 shows an outline of the “torque peeling test method” defined in JIS-B1196, and FIG. 3 shows the test results. In FIG. 3, “•” is an average value of measurement values (representative measurement value of each system), and a solid line graph connects the average values. In the torque peeling test, the socket 34 of the torque wrench 32 is fitted on the aluminum alloy projection welding nut 10 that is projection welded to the aluminum alloy panel 22, and the torque wrench 32 is rotated in this state to apply torque. By doing so, the torque peel strength is measured. As can be seen from the test results of FIG. 3, the torque peel strength also shows a high value for the 2000 series and 5000 series aluminum alloy materials, and the 6000 series aluminum alloy material shows the lowest values.

  Furthermore, the measurement result of the post-weld screw strength of the aluminum alloy projection welding nut 10 is shown in FIG. In FIG. 4, “•” is the average value of the measured values, and the solid line graph connects the average values. From this test result, it can be seen that the post-weld screw strength is highest for the 7000 series aluminum alloy material and lowest for the 6000 series aluminum alloy material.

  Based on the test results described above, in the aluminum alloy projection welding nut 10 according to the present embodiment, the projection portion 16 is made of a 5000 or 2000 series aluminum alloy material having a high peel strength, and the screw portion 14 has a high screw strength. Since the aluminum alloy projection welding nut 10 is projection welded around the bolt insertion hole 24 of the aluminum alloy panel 22, sufficient joint strength and sufficient screw strength are obtained. Either can be secured. That is, according to the projection welding nut 10 made of aluminum alloy according to the present embodiment, the projection welding nut made of aluminum alloy by combining two types of aluminum alloy materials having different properties so that the advantages of each aluminum alloy material can be utilized. Since 10 is configured, it is possible to achieve both securing of joint strength and securing of screw strength.

  Further, in the aluminum alloy projection welding nut 10 according to the present embodiment, the projection portion 16 and the screw portion 14 are formed separately, and the engagement groove 16B provided in the projection portion 16 is provided in the screw portion 14. Since the projection portion 16 and the screw portion 14 are integrated by caulking and fixing to 20, the projection portion 16 and the screw portion 14 can be easily manufactured, and the projection portion 16 and the screw portion 14 can be easily manufactured. The joining accuracy can be ensured relatively easily. As a result, according to the aluminum alloy projection welding nut 10 according to the present embodiment, both productivity and reliability can be improved.

  Furthermore, in the aluminum alloy projection welding nut 10 according to the present embodiment, a 2000-series or 5000-series aluminum alloy material is used for the projection portion 16 and a 7000-series aluminum alloy material is used for the screw portion 14. A composite nut is constructed that takes advantage of the features of aluminum alloy materials. As a result, the cost can be reduced as compared with the case of manufacturing (developing) an aluminum alloy projection weld nut in which a complicated configuration other than the material is added to obtain the same effect as the present embodiment.

  In addition, according to the aluminum alloy projection welding nut 10 according to the present embodiment, the following effects can be obtained.

  First, when compared with a steel nut coated with an aluminum alloy, it is possible to avoid the inclusion of iron as an impurity when the aluminum body is redissolved and recycled as an aluminum material. Therefore, it is excellent in recyclability in the sense that it can be recycled with high purity.

  Second, when compared with a steel nut covered with an aluminum alloy, it is not necessary to remove the iron nut during recycling. Therefore, it is excellent in recyclability in the sense that it does not take time and effort.

  Third, for example, in the case where the entire aluminum alloy projection weld nut is made of a 5000 series aluminum alloy material, the screw strength is inferior to that of the aluminum alloy projection weld nut 10 according to the present embodiment. It is necessary to increase the axial length of the threaded portion. However, in the case of the aluminum alloy projection welding nut 10 according to the present embodiment, the screw strength can be increased because the different materials are used in combination. Therefore, the aluminum alloy projection welding nut can be reduced in size accordingly.

  Fourth, in the case of the configuration disclosed in Patent Document 1 cited as the prior art, the insert made of aluminum alloy comes into line contact with both the nut and the panel, so that the joining strength corresponding to the conventional projection protrusion is obtained. However, according to the projection welding nut 10 made of the aluminum alloy according to the present embodiment, the point welding projection welding by the protrusion can be maintained as usual, so that the current value at the time of welding is obtained. Can be lowered. Therefore, power consumption can be reduced.

  In addition, in the aluminum alloy projection welding nut 10 shown in FIG. 1 described above, not only a plurality of protrusions 16C (and a plurality of caulking portions 16B) corresponding to a substantial projection portion but also a base for the screw portion 14. The substantially ring plate-shaped flange portion 16A is also made of an aluminum alloy material of 5000 series or 2000 series. However, the present invention is not limited to this, and as shown in FIG. The projection part 40 may be constituted only by this, and this part may be a projection welding nut 42 made of an aluminum alloy made of a 5000 series or 2000 series aluminum alloy material. In this case, when viewed in comparison with FIG. 1, the height of the screw portion 44 is somewhat high, and the projection portion 40 is constituted by a plurality of protrusions 40 </ b> A and a plurality of caulking portions 40 </ b> B.

[Second Embodiment]
Next, a second embodiment of the aluminum alloy projection welding nut according to the present invention will be described with reference to FIG. In addition, about the same component as 1st Embodiment mentioned above, the same number is attached | subjected and the description is abbreviate | omitted.

  As shown in FIG. 8, in the second embodiment, a nut main body 52 having a threaded portion 50, and the nut main body 52 are configured separately and independently, and a plurality of projection protrusions 54 and 56 are provided on the front and back surfaces. There is a feature in that an aluminum alloy projection welding nut 60 is configured by a combination with the integrally formed washer 58. Note that the projection protrusions 54 and 56 and the washer 58 correspond to the projection portion of the third aspect.

  In this case, the projection protrusions 54 and 56 and the washer 58 are made of a 5000 series or 2000 series aluminum alloy material, and the nut body 52 is made of a 7000 series aluminum alloy material.

  According to the above configuration, the washer 58 provided with the projection protrusions 54 and 56 on the front and back surfaces is interposed between the aluminum alloy panel 22 and the nut body 52, and projection welding is performed in this state. As a result, the projection projection 54 on the front surface side of the washer 58 is melted and the washer 58 is joined to the nut body 52, and the projection projection 56 on the back surface side of the washer 58 is melted and the washer 58 is joined to the aluminum alloy panel 22. The

  In this way, even if the screw portion 50 and the projection portion are separately configured, the washer 58 including the projection protrusions 54 and 56 is made of a 5000 or 2000 series aluminum alloy material having a high peel strength, and the screw portion 50 Since the nut main body 52 including 7000 is made of a 7000 series aluminum alloy material having high screw strength, it is possible to achieve both securing of joint strength and securing of screw strength as in the first embodiment described above.

  Moreover, since the screw part 50 and the projection part are comprised independently separately, and it is the structure integrated at the time of welding, a caulking process becomes unnecessary. Therefore, the manufacturing process of the aluminum alloy projection welding nut 60 can be reduced. As a result, the merit that the production line length can be shortened is obtained.

  In the first and second embodiments described above, the projection welding nut made of aluminum alloy applied to the aluminum body of the automobile has been described. However, the invention is not limited to this, and the projection made of aluminum alloy used for applications other than automobiles. The present invention may be applied to a welding nut.

It is a front view which cut | disconnects one side and shows the whole structure of the aluminum alloy projection welding nut which concerns on 1st Embodiment. It is a graph which shows the result of an indentation peeling test. It is a graph which shows the result of a torque peeling test. It is a graph which shows the result of a post-weld screw strength test. It is a whole block diagram which shows the outline | summary of the "indentation peeling test method." It is a whole block diagram which shows the outline | summary of the "torque peeling test method". It is a front view corresponding to FIG. 1 which shows the modification of the aluminum alloy projection welding nut shown by FIG. It is a front view which cuts and shows the whole structure of the aluminum alloy projection welding nut which concerns on 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Aluminum alloy projection welding nut 12 Female screw 14 Screw part 16 Projection part 16B Caulking part 22 Aluminum alloy panel 40 Projection part 40B Caulking part 44 Screw part 50 Screw part 52 Nut main body 54 Projection protrusion (projection part)
56 Projection protrusion (projection part)
58 Washer (Projection Department)
60 Aluminum alloy projection weld nuts

Claims (4)

An aluminum alloy projection welding nut joined to the aluminum alloy panel by projection welding,
The projection part, which is a joint part to the aluminum alloy panel, is composed of a first aluminum alloy material having high peel strength, and the thread part on which the internal thread is formed is composed of a second aluminum alloy material having high screw strength.
An aluminum alloy projection welding nut characterized by the above. The projection part and the screw part are configured separately, and the projection part and the screw part are integrated by caulking one to the other,
The aluminum alloy projection welding nut according to claim 1. The projection part is configured by a washer configured independently of the nut main body having the screw part, and a projection protrusion provided integrally on the front and back surfaces of the washer.
The aluminum alloy projection welding nut according to claim 1. The first aluminum alloy material is a 2000 series or 5000 series aluminum alloy material, and the second aluminum alloy material is a 7000 series aluminum alloy material.
The projection weld nut made of aluminum alloy according to any one of claims 1 to 3.

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