JP2000048871A - Connecting structure of conductive metallic meterial by seal bolt - Google Patents

Abstract

PROBLEM TO BE SOLVED: To keep electrical conductivity on the connecting surface of a metallic material, in a connecting structure of a conductive meterial plate by a seal bolt. SOLUTION: A connector (made of aluminum) 31 of a shield cable having a hole 32, through which a seal bolt 10 is to be inserted and a connector connecting part (made of aluminum) 21 having an internal threaded hole 22 to which the bolt 10 is to be screwed are connected to each other by the seal bolt 10, in which a sealing meterial is filled in the screw root of the bolt 10. A sealing material storing groove 24 having a large diameter is formed on the opening part of the internal threaded hole 22, and the capacity of the sealing material storing groove 24 is set to such the capacity as to sufficiently house (store) sealing material overflowing from the internal threaded hole 22, when the seal bolt 10 is screwed to the internal threaded hole 22.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for joining conductive metal materials with seal bolts, and more particularly, to a method for joining conductive metal materials to each other using seal bolts. To the realization of a joint structure that satisfactorily holds the pressure.

[0002]

2. Description of the Related Art Conventionally, when electrically conductive metal materials are mechanically joined to each other with bolts, good electrical continuity can be ensured at the joint surface by suppressing an increase in electric resistance at the joint surface. Required, and various methods proposed for it,
It is also in practical use (for example, Japanese Utility Model Laid-Open No. 4-49459).
JP-A-9-161890, etc.).

In general, when a case body of a motor or the like is cast from a conductive metal material such as aluminum, cavities (blow holes and the like) are unavoidably generated at the time of casting. When joining a metallic connector or the like to a conductive metal material having such a nest, a seal bolt 10 shown in FIG. 6 is used to ensure the sealing property of the material. This seal bolt 10
As shown in FIG. 6, for example, the pre-coating type reactive sealing agent 11 is filled in the thread root portion 10a. The sealing agent 11 is formed of, for example, an acrylic or epoxy resin, and has an electrical property of insulating.

FIGS. 7 and 8 show an example in which a shield cable incorporating various signal lines is joined to a motor case body and an inverter, for example, in an electric vehicle using the seal bolt 10.

In FIG. 7, a connector portion (hereinafter simply referred to as a connector portion) 31 of a shielded cable 30 is connected to a connector connecting portion 21 formed integrally with a case body of a motor made of a conductive metal material such as aluminum. Are connected. The connector portion 31 is formed of, for example, a conductive metal material such as aluminum similarly to the connector connection portion 21. The connector portion 31 includes a through hole 32 through which the seal bolt 10 is inserted, and the connector connection portion. A joint portion 33 and the like to be fitted in the cable hole 23 provided in 21 are formed.

The other end of the sealing cable 30 (not shown) is also provided with the connector 31. The surface of the shielded cable 30 is shielded wire 3
0a, and the shield line 30a and the connector portion 31 are electrically connected. In addition to the cable hole 23, a female screw hole 22 for screwing the seal bolt 10 is formed in the connector connection portion 21.

Next, FIG. 8 shows a cross section of a mode in which the shield cable 30 is joined to the case 20 of the motor and the case 40 of the inverter using the seal bolt 10. The case 40 of the inverter is also formed of a conductive metal material such as aluminum.

As shown in FIG. 8, a plurality of electric signal lines 30b built in the shielded cable 30
The motor and an inverter that controls the driving of the motor are electrically connected. At this time, the plurality of electric signal lines 30b are connected to the shield case 30a connected to the case 20 of the motor and the case 40 of the inverter via the connector 31.
Covered by That is, since the case body 20 of the motor and the case 40 of the inverter are normally set to the ground potential, the plurality of electric signal lines 30b are covered with a shield line 30a joined to the same and also set to the ground potential. Emission of electromagnetic noise accompanying inverter control is suppressed.

[0009]

By the way, as shown in FIG. 6, the above-mentioned seal bolt 10 has its valley portion 1 of the screw.
The sealing agent 11 is coated on 0a. For this reason, for example, on the case body 20 side of the motor, the connector connection portion 2 of the motor is arranged in a manner shown in FIG.
When the connector portion 31 of the shielded cable 30 is joined to the female connector 1, a female screw hole 22 provided in the connector connection portion 21 is provided.
The sealing agent 11 is removed from the seal bolt 10 with the screwing and tightening of the seal bolt 10 to
The removed sealant 11 may overflow from the screw hole 22. In this case, as shown in FIG. 9B, which is a partially enlarged view of FIG. 9A, the overflowing sealing agent 11 is applied to the joining surface 31 of the connector portion 31.
a and the connecting surface 21a of the connector connecting portion 21 may enter the gap K, and the connection resistance between the connector portion 31 and the connector connecting portion 21 may increase. When the connection resistance increases, the electrical continuity between the connector section 31 and the connector connection section 21 deteriorates, and the noise shielding effect of the shielded cable 30 decreases. Therefore, electromagnetic noise generated from the motor, the inverter, and the like leaks to the outside of the case, which adversely affects other electric devices.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a method for joining conductive metal materials to each other using seal bolts. An object of the present invention is to provide a joint structure of a conductive metal material by a seal bolt capable of maintaining good electrical conductivity of the conductive metal material.

[0011]

In order to achieve the above object, according to the first aspect of the present invention, there is provided a joining structure of a conductive metal material using a seal bolt, wherein a sealing agent is filled in a thread root of the bolt. A conductive metal formed by a seal bolt for joining a first conductive metal material having a hole through which the bolt is penetrated and a second conductive metal material having a female screw hole into which the bolt is screwed by the seal bolt The gist of the present invention is a material bonding structure including a sealing agent intrusion prevention mechanism for preventing the sealing agent from intruding into the first and second conductive metal material bonding surfaces.

In the above structure, when the first conductive metal material and the second conductive metal material are joined using the seal bolt, the sealing agent is prevented from being applied to both metals by the sealing agent intrusion preventing mechanism. The material is prevented from penetrating the bonding surface. Therefore, even when the conductive metal materials are bonded to each other by the seal bolt, the conductivity of the bonding surface of the two metal materials is well maintained.

According to a second aspect of the present invention, in the joining structure of a conductive metal material by the seal bolt according to the first aspect, the sealing agent intrusion prevention mechanism is provided with the first conductive metal material. A reservoir through which the sealing agent is accommodated and which is provided with at least one of a hole through which a bolt is passed, and a female screw hole into which the bolt of the second conductive metal material is screwed, and which is provided with an enlarged diameter; The gist consists of

In the above construction, when the first and second conductive metal materials are joined together, when the seal bolt is screwed into the female screw hole and tightened, the sealing agent overflows from the female screw hole. Even in such a case, the sealing agent is accommodated in the reservoir groove. Therefore, it is possible to effectively prevent the sealing agent from invading the joint surface between the two metal materials. Further, the sealing agent intrusion prevention mechanism can be easily formed only by expanding the opening of the female screw hole to which the bolt of the second conductive metal material is screwed.

According to a third aspect of the present invention, in the joining structure of a conductive metal material by the seal bolt according to the first aspect, the sealing agent intrusion preventing mechanism is provided in the second conductive metal material. A sleeve extending from a hole through which the bolt of the first conductive metal material is inserted so as to be fitted into an enlarged diameter opening of a female screw hole into which the bolt is screwed; Is the gist.

According to a fourth aspect of the present invention, in the joining structure of a conductive metal material by the seal bolt according to the first aspect, the sealing agent intrusion prevention mechanism is provided in the first conductive metal material. A sleeve extending from an opening of a female screw hole into which the bolt of the second conductive metal material is screwed so as to be fitted into a large-diameter opening of the hole through which the bolt is inserted; The gist is that it is done.

According to the third and fourth aspects of the present invention, when the first and second conductive metal materials are joined together, the seal bolt is screwed into the female screw hole and tightened.
Even if the sealing agent overflows from the female screw hole, the sleeve extends from the hole through which the bolt penetrates, or the sleeve extends from the opening of the female screw hole. The bonding surface of the conductive metal material and the sealing agent are completely separated. Therefore, it is possible to effectively prevent the sealing agent from invading the joint surface.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] Hereinafter, a first embodiment in which a joint structure of a conductive metal material using a seal bolt according to the present invention is applied to a joint between a motor of an electric vehicle and a shielded cable thereof will be described. The embodiment will be described in detail with reference to FIGS.

FIG. 1 is a schematic sectional view of the joint structure according to the present embodiment, and FIG. 2 is a partially enlarged view of FIG. FIG.
In FIG. 2 and FIG. 2, the same elements as those of the conventional joining structure shown in FIGS. 6 to 8 are denoted by the same reference numerals, and redundant description of those elements will be omitted.

As shown in FIGS. 1 and 2, even in the joint structure of this embodiment, the thread valley 10a is filled with, for example, a pre-coating type reactive sealing agent 11 as a fastening bolt. A seal bolt 10 (see FIG. 6) is used. In addition, a connector (made of aluminum) 31 of the shielded cable 30, which is one conductive metal material to be joined, is provided with a through hole 32 for allowing the seal bolt 10 to pass therethrough. A female screw hole 22 into which the seal bolt 10 is screwed is provided in a connector connecting portion 21 formed integrally with a motor case main body (made of aluminum) of an electric vehicle, which is a conductive metal material.

In the present embodiment, the female screw hole 22 is formed with a sealing agent reservoir groove 24 provided with an enlarged diameter at the opening thereof. The capacity of the sealant storage groove 24 is such that the seal bolt 10 is
When the screw is screwed into the hole 2, the sealing agent 11 has a volume capable of sufficiently containing (storing) the sealing agent 11 overflowing from the female screw hole 22. That is, the volume of the sealing agent 11 is set to a sufficient level to prevent the sealing agent 11 overflowing from the female screw hole 22 from reaching the joint surface between the connector connecting portion 21 and the connector portion 31. The diameter and depth of the sealing agent reservoir groove 24 are arbitrarily determined from this volume. Note that the sealing agent reservoir groove 24 can be easily formed simply by expanding the opening of the female screw hole 22.

Next, the operation of such a joint structure will be described. In the joint structure, as described above, the sealant storage groove 24 is provided at the opening of the female screw hole 22. Therefore, the connector part 31 and the connector connection part 21 of the shielded cable 30 are
When joining by the female screw hole 2 of the seal bolt 10
The sealant 11 that has been removed from the seal bolt 10 with the screwing and tightening of the sealant 2 and overflowing from the female screw hole 22 is sequentially accommodated in the sealant reservoir groove 24. Therefore, the overflowed sealing agent 11 does not enter the joint surface between the connector portion 31 and the connector connection portion 21, and the connector portion 31 and the connector connection portion which maintain the electrical conductivity of the joint surface in good condition. 21
Can be joined. Therefore, the shielded cable 3
0 also effectively secures the electromagnetic noise shielding effect.

FIG. 3 shows the connection structure between the connector portion 31 and the connector connection portion 21 in the case where the sealing agent reservoir groove 24 is provided and the case where the sealing agent reservoir groove 24 is not provided. It is a graph showing the change with time. That is, in FIG. 3, graph A shows the case where the sealing agent reservoir groove 24 was not provided (conventional joining structure), and graph B shows the case where the sealing agent reservoir groove 24 was provided (the joining structure of the present embodiment). The change over time is shown. Graph C shows, for reference, the change over time when a normal bolt is used without using the seal bolt 10. Each of these graphs was obtained by experiments by the inventors. As is apparent from FIG. 3, by providing the sealing agent reservoir groove 24, an increase in the resistance value between the joining surfaces due to the use of the seal bolt 10 is significantly suppressed.

As described above, according to the joint structure of the first embodiment, the following effects can be obtained. (1) In the present embodiment, since the sealing agent reservoir groove 24 is provided in the opening of the female screw hole 22 of the connector connection portion 21, the sealing agent 1 overflowing from the female screw hole 22 is provided.
1 can be accommodated in the sealing agent reservoir groove 24,
As a result, it is possible to preferably prevent the sealing agent 11 from entering the joint surface between the connector portion 31 and the connector connection portion 21. As a result, the connector portion 3 having good electrical continuity of the joint surfaces is obtained.
1 and the connector connecting portion 21 can be joined, and the shielding performance of the electromagnetic noise by the shielded cable 30 can be secured well. Therefore, leakage of the electromagnetic noise generated from the motor, the inverter, and the like to the outside of the case is suppressed, and the electromagnetic noise is preferably prevented from adversely affecting other electric devices. Moreover, the sealing agent reservoir groove 24 can be easily formed simply by expanding the opening of the female screw hole 22.

In the first embodiment,
The sealing agent 11 is connected to the connector 31 and the connector connection 2.
Although an example is shown in which the sealing agent reservoir groove 24 for suitably preventing intrusion into the joint surface with the groove 1 is provided by enlarging the opening of the female screw hole 22, the present invention is not limited to this. For example, the sealing agent reservoir groove 24 may be provided by increasing the diameter of the opening of the through hole 32 of the connector 31, or both the opening of the female screw hole 22 and the opening of the through hole 32 may be provided. The diameter may be increased.

In the first embodiment,
Although the example in which the shape of the sealing agent reservoir groove 24 is formed in a cylindrical shape has been described, the present invention is not limited to this. The shape of the reservoir groove 24 may be anything as long as it has a cross-sectional area larger than the cross-sectional area of the female screw hole 22 and is provided in the opening of the female screw hole 22, for example, a square cross-section. It may be a quadrangular prism or other polygonal prisms.

[Second Embodiment] Next, a description will be given of a second embodiment in which the joining structure of a conductive metal material by a seal bolt according to the present invention is similarly applied to the joining of a motor of an electric vehicle and its shielded cable. 4 and FIG. Note that, here, the description will be made focusing on the differences from the joint structure of the first embodiment.

In the joint structure according to the second embodiment shown in FIGS. 4 and 5, the sealing agent 11 enters the gap between the joint surface 31a of the connector 31 and the joint surface 21a of the connector connection 21. A sleeve (sleeve-shaped cylinder) 50 is used as a mechanism for preventing the above-mentioned phenomenon, that is, a sealing agent intrusion preventing mechanism, instead of the sealing agent reservoir groove 24 in the first embodiment. In addition, this sleeve 5
0 is formed of a hard resin.

That is, the connector 31 and the connector connection 21 of the shielded cable 30 are
4, the sleeve 50 is extended by inserting the sleeve 50 into a sleeve insertion groove 22a formed by expanding the female screw hole 22 in the opening of the female screw hole 22 as shown in FIG. I do. Then, when the connector portion 31 is joined to the connector connection portion 21, the through hole 32 ′ formed in the connector portion 31 (the diameter is increased as compared with the through hole 32 with the introduction of the sleeve 50). This sleeve 5
0, the seal bolt 10 is inserted into the sleeve 50, and the seal bolt 10 is screwed into the female screw hole 22 to thereby form the connector portion 31 and the connector connection portion 21.
And are joined.

At this time, the sealing agent 11 which has overflowed from the female screw hole 22 accumulates between the sleeve 50 and the seal bolt 10 as shown in FIG. Joint surface 21 of part 21
It does not invade between a. Therefore, it is possible to join the connector portion 31 and the connector connection portion 21 while maintaining good electrical conductivity between the joining surfaces 21a and 31a. Thereby, similarly to the above-described first embodiment,
The shielding performance of the electromagnetic noise by the shielded cable 30 is also ensured well, the electromagnetic noise generated from the motor and the inverter is prevented from leaking out of the case, and the electromagnetic noise may adversely affect other electric devices. Is prevented.

As described above, according to the joint structure of the second embodiment, the following effects can be obtained. (2) In the present embodiment, the sleeve 50 is
The sealing agent 11 that overflows from the female screw hole 22 can accumulate between the sleeve 50 and the seal bolt 10 by being inserted and extended into the sleeve insertion groove 22a provided in the opening of Thus, it is possible to preferably prevent the sealing agent 11 from entering the joint surface between the connector portion 31 and the connector connection portion 21. As a result, it becomes possible to join the connector portion 31 and the connector connection portion 21 with good electrical continuity of the joining surfaces, and the shielding performance of the shield cable 30 for electromagnetic noise is also ensured. Therefore, leakage of the electromagnetic noise generated from the motor, the inverter, and the like to the outside of the case is suppressed, and the electromagnetic noise is preferably prevented from adversely affecting other electric devices.

In the second embodiment,
The example in which the sleeve 50 is formed of a hard resin has been described, but is not limited thereto. That is, the sleeve 50
May be formed of metal, for example, or may be formed of a thin flexible resin.

In the second embodiment,
When the connector part 31 is joined to the connector connection part 21, an example has been shown in which the sleeve 50 is first inserted into the sleeve insertion groove 22 a provided in the opening of the female screw hole 22 and extended in a state of being extended. Alternatively, the sleeve 50 may be first inserted into the through hole 32 ′ formed in the connector portion 31 and joined in an extended state. In addition, sleeve 5
0 may be formed integrally with and extended from the connector connection portion 21 or the connector portion 31.

In each of the above embodiments, as an example in which conductive metal materials are joined to each other by the seal bolt 10, the connector connecting portion 21 of the motor case main body is used.
Although the example in which the connector (made of aluminum) 31 of the shielded cable 30 is joined to (made of aluminum) is shown, the invention is not limited to this. The present invention can be applied to the joining of any conductive metal material as long as it is a joint between conductive metal materials requiring good electrical conduction. The material of the metal is not limited to aluminum.

Next, technical ideas other than the inventions described in the claims, which can be understood from the above embodiments, will be described below together with their effects. (1) In the joint structure of a conductive metal material by a seal bolt according to any one of claims 1 to 4,
The conductive metal material is a connector of a shielded cable, and the second conductive metal material is a structure in which the conductive metal material is joined by a seal bolt which is a connector connecting portion provided on a motor case body.

According to the configuration described in (1), for example, when the shielded cable is applied to a cable connecting an inverter for motor control and a motor of an electric vehicle, leakage of electromagnetic noise from the shielded cable is preferably reduced. Can be suppressed.

[0037]

According to the first aspect of the present invention, the sealing agent is prevented from entering the bonding surface of the first and second conductive metal materials by the sealing agent entry preventing mechanism. Therefore, even when the conductive metal materials are bonded to each other by the seal bolt, the conductivity of the bonding surface of the two metal materials is well maintained.

According to the second aspect of the present invention, even when the sealing agent overflows from the female screw hole at the time of joining the first and second conductive metal materials, the sealing agent does not It is stored in the storage groove. Therefore, it is possible to effectively prevent the sealing agent from invading the joint surface between the two metal materials. Further, the sealing agent intrusion prevention mechanism,
For example, it can be easily formed only by expanding the opening of the female screw hole into which the bolt of the second conductive metal material is screwed.

According to the third and fourth aspects of the present invention, the sleeve extending from the hole through which the bolt penetrates or the sleeve extending from the opening of the female screw hole is provided.
The bonding surface of the first and second conductive metal materials and the sealing agent are completely separated. Therefore, the sealing agent is effectively prevented from entering the joint surface.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing a first embodiment of a bonding structure according to the present invention.

FIG. 2 is a partially enlarged view of FIG.

FIG. 3 is a graph showing a change over time in a junction resistance between conductive metal materials.

FIG. 4 is a perspective view showing a second embodiment of the joining structure according to the present invention.

FIG. 5 is a sectional view showing a sectional structure of the joint structure according to the second embodiment;

FIG. 6 is a side view showing a seal bolt.

FIG. 7 is a perspective view showing an assembling mode of a conventional joining structure.

FIG. 8 is a sectional view showing an example of a wiring shield structure between a motor and an inverter in an electric vehicle or the like.

FIG. 9 is a cross-sectional view showing an example of a conventional bonding structure and a partially enlarged view thereof.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... Seal bolt, 11 ... Sealing agent, 20 ... Motor case main body, 21 ... Connector connection part, 22 ... Female screw hole, 22a ... Sleeve insertion hole, 24 ... Sealing agent storage groove, 30 ... Shield cable, 31 ... Shield Connector part of cable, 32: through-hole, 40: case of inverter, 50: sleeve.

Claims (4)

[Claims] A first conductive metal material having a hole through which the bolt is inserted and a female screw hole through which the bolt is screwed by a seal bolt in which a sealing agent is filled in a thread root of the bolt. A bonding structure of a conductive metal material by a seal bolt for bonding to a second conductive metal material, wherein the sealing agent prevents the sealing agent from entering the first and second conductive metal material bonding surfaces. What is claimed is: 1. A structure for joining a conductive metal material with a seal bolt, comprising a penetration preventing mechanism. 2. The sealing agent intrusion prevention mechanism includes a hole through which the bolt of the first conductive metal material is inserted, and a female screw hole into which the bolt of the second conductive metal material is screwed. 2. The structure according to claim 1, further comprising a reservoir groove provided in at least one of the opposing openings so as to be enlarged in diameter and containing the sealing agent. 3. The sealing agent intrusion prevention mechanism includes a first conductive material that is fitted into an enlarged-diameter opening of a female screw hole into which the bolt of the second conductive metal material is screwed. 2. The structure according to claim 1, further comprising a sleeve extending from a hole through which the bolt of the metal material passes. 4. The sealing agent intrusion prevention mechanism includes a first conductive metal material, the second conductive metal material being fitted into a large-diameter opening of a hole through which the bolt passes. 2. The structure according to claim 1, further comprising a sleeve extending from an opening of the female screw hole into which the bolt is screwed.