JP2014089929A - Waterproof connector for automobile - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a waterproof connector capable of preventing abrasion of a terminal contact point by suitably absorbing vibration from an electric wire, and of suppressing an increase in cost caused by addition of components and the like.SOLUTION: In a waterproof connector 1, a terminal cavity 7 (7a or 7b) housing a terminal, such as a male terminal and a female terminal and the like, is provided to a housing 6, and a rubber stopper 11 into which an insulation electric wire 8 is inserted is inserted into an inlet of the terminal cavity 7 to make the terminal cavity 7 waterproof by means of the rubber stopper 11. The rubber stopper 11 is a cylindrical body having a diameter larger than that of the inlet of the terminal cavity 7, and has a through-hole into which the insulation electric wire can be inserted. A high-hardness part 11A and a low-hardness part 11B having a hardness lower than that of the high-hardness part 11A are formed in a region having a predetermined length in the through-hole direction.

Description

  The present invention relates to a waterproof connector mounted on an automobile.

  The waterproof connector for automobiles may be required to have vibration resistance. For example, a connector that is directly connected to an engine is greatly subjected to vibration. When vibration is applied to the connector, relative movement occurs between the male and female housings and terminals, and the terminal contact portion of the connector is worn.

  Conventionally, in order to prevent wear of the terminal contact portion of the connector due to vibration, for example, by suppressing the relative displacement between the male and female housings, the relative movement between the male and female terminals is eliminated to prevent wear of the terminal contact portion. It is known (see, for example, Patent Document 1).

Japanese Patent No. 4561708 ([0037], FIG. 8, FIG. 9)

  As shown in FIG. 5, the waterproof connector 100 for an automobile has a rubber plug 104 attached to, for example, a cavity inlet 103 of a terminal cavity 102 of a connector housing 101. The rubber plug 104 is a part provided for waterproofing purposes so as to be inserted into the cavity inlet 103 and to maintain airtightness in the cavity 102.

  The rubber plug 104 of the waterproof connector has a through hole for inserting the electric wire 105 at the center, and has a diameter larger than the diameter of the terminal cavity 102. When the rubber plug 104 is inserted into the terminal cavity 102, the rubber plug 104 is compressed between the wire covering material and the cavity wall surface. Since the rubber plug 104 is in close contact with the inner surface of the terminal cavity 102 due to rubber elasticity, airtightness inside the cavity 102 is ensured.

  Conventionally, the rubber plug 104 of the waterproof connector 100 has been designed to exhibit waterproof performance. However, the rubber plug 104 does not consider any vibration countermeasures.

  In the automobile equipped with the waterproof connector shown in FIG. 5, when an engine vibration or a vibration due to running occurs, a vibration load is applied to the electric wire 105, and the female terminal 106 and the male terminal 107 connected to the electric wire 105 vibrate. To do. In the connector 100, a male terminal 107 is fitted to a female terminal 106. The terminal contact portion 108 of the female terminal 106 and the male terminal 107 moves while the terminals are in contact with each other, so that the terminal contact is worn.

^2. Description of the Related Art In recent years, a large current connector for HEV and EV vehicles has been used with a thick electric wire having a wire diameter of 15 to 50 mm ² . When the electric wire becomes thicker, the vibration load applied to the electric wire when receiving vibration is also increased. For this reason, there is a possibility that vibrations cannot be sufficiently suppressed by the conventional method of backlashing between the male and female housings to suppress the sliding between the terminals. If suppression of vibration becomes insufficient, there is a high possibility that terminal contact wear will occur due to load input from the electric wire.

  Thus, in the waterproof connector, in order to suppress wear of the terminal contact, further measures for preventing the vibration load from the electric wire from being transmitted to the terminal are required. In addition, it is not preferable to add another part such as an electric wire fixing member as such a countermeasure because the cost increases.

  The present invention is intended to solve the above-mentioned drawbacks of the prior art, and can absorb vibrations from the electric wires to prevent the terminal contact portions from being worn, and the cost of adding parts can be reduced. It is an object of the present invention to provide a waterproof connector that can suppress the rise.

In order to solve the above problems, the waterproof connector of the present invention is
A fitting terminal connected to the conductor of the insulated wire and a terminal cavity for housing the fitting terminal are provided in the housing, and a rubber plug into which the insulated wire is inserted is inserted into the inlet of the terminal cavity. A waterproof connector in which the inside of the terminal cavity is waterproofed by the rubber plug,
The rubber plug is a cylindrical body larger than the diameter of the inlet of the terminal cavity, has a through-hole having a size through which the insulated wire can be inserted, and has a hardness higher than that of the high hardness portion and the high hardness portion. The gist is that the low hardness portion is formed in a region having a predetermined length in the through-hole direction.

  In the waterproof connector of the present invention, the rubber plug is a cylindrical body larger than the diameter of the terminal cavity, and has a through-hole having a size into which the insulated wire can be inserted, and the through-hole of the rubber plug By having a high hardness part formed in a region of a predetermined length in the direction and a low hardness part whose hardness is lower than the high hardness part, the high hardness part ensures sufficient waterproof performance and is flexible. Wear of the terminal contact can be prevented by suppressing the displacement of the terminal and the housing due to the load applied from the insulated wire due to vibration by the low hardness portion formed in. In particular, even when used as a connector for a thick insulated wire used at a large current, it is possible to suppress vibrations and favorably suppress wear of terminal contacts.

  Furthermore, the waterproof connector of the present invention only needs to change the hardness of the rubber plug, and other components can use the same configuration as the conventional one as it is. Since the present invention does not require the addition of special parts other than the rubber plug, it is possible to minimize the increase in cost and to take measures for waterproofing and wear at low cost.

FIG. 1 is a sectional view showing a male-female fitting type connector as an example of the waterproof connector of the present invention. 2A is an enlarged cross-sectional view of a main part of the waterproof connector of FIG. 1, and FIG. 2B is an external perspective view of a rubber plug. FIG. 3 is a sectional view showing another example of the waterproof connector of the present invention. FIG. 4 is an explanatory view showing a test method of the terminal displacement amount of the waterproof connector. FIG. 5 is a cross-sectional view showing a conventional waterproof connector.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a male / female terminal fitting type connector as an example of a waterproof connector. A waterproof connector 1 of the embodiment shown in FIG. 1 is a male / female fitting type automotive waterproof connector 1 formed so that a male connector 3 having a male terminal 2 is fitted to a female connector 5 having a female terminal 4. is there.

  In the male connector 3, a male terminal cavity 7a is provided in a housing 6a made of a plastic molded product. The male terminal 2 is mounted in the male terminal cavity 7a. A conductor 9 of an insulated wire 8 in which the conductor 9 is covered with a covering material 10 made of an insulator is crimped and electrically connected to the male terminal 2.

  Similarly to the male connector 2, the female connector 5 is provided with a female terminal cavity 7 b in a housing 6 b made of a plastic molded product. A female terminal 4 is attached in the female terminal cavity 7b. A conductor 9 of an insulated wire 8 is crimped and electrically connected to the female terminal 4.

  The male terminal 2 and the female terminal 4 are fitting terminals. When the male connector 3 and the female connector 5 are fitted, the male terminal 2 of the male connector 3 is fitted and brought into contact with the female terminal 4 of the female connector 5 and is electrically connected by a contact portion between the terminals. Yes.

The connector shown in FIG. 1 is an example of a high-voltage electric wire connector used for a high-voltage electric wire as an electric wire. As the high-voltage electric wire, an electric wire having a larger outer diameter is used as compared with the low-voltage electric wire. As a specific high-voltage electric wire, one having a wire diameter in the range of 15 to 50 mm ² is used.

  2A is an enlarged cross-sectional view of a main part of the waterproof connector of FIG. 1, and FIG. 2B is an external perspective view of a rubber plug. As shown in FIGS. 1, 2 (a), and 2 (b), the insulated wire 8 connected to the male terminal 2 and the female terminal 4 is inserted through the through hole 13 of the waterproof rubber plug 11. The rubber plugs 11 and 11 into which the insulated wires 8 are inserted are respectively inserted into the inlet sides of the male terminal cavity 7a and the female terminal cavity 7b.

  The same rubber plug 11 and insulated wire 8 on the male terminal 2 side and rubber plug 11 and insulated wire 8 on the female terminal 4 side are used. The male terminal cavity 7a and the female terminal cavity 7b are formed to have the same inlet diameter. The terminal cavities 7a and 7b may be collectively referred to as a terminal cavity 7.

  The rubber plug 11 is formed in a cylindrical shape whose outer diameter is larger than the inner diameter of the terminal cavity 7. A through hole 13 having a size capable of inserting the insulated wire 8 is provided in the approximate center of the rubber plug 11. The size of the through hole 13 is substantially the same as or slightly smaller than the outer diameter of the insulated wire 8.

  As shown in FIG. 2B, the front and back surfaces of the rubber plug 11 in the through hole direction are formed in a planar shape. In addition, on the surface of the rubber plug 11 on the cavity wall surface side, three ridges 14 extending in the outer peripheral direction are provided, and the surface is formed in an uneven shape. In addition, three convex shapes extending in the inner circumferential direction are also provided on the surface of the through-hole 13 serving as the inner surface of the rubber plug 11 and are formed in an uneven shape. In FIG. 2A, the protrusions of the rubber plug are not shown.

  Further, the outer diameter G of the rubber plug 11 is formed larger than the diameter of the terminal cavity 7. Therefore, when the rubber plug 11 is inserted into the terminal cavity 7, the rubber plug 11 is compressed and is pressed against the wall surface of the terminal cavity 7 by the elastic force of rubber. By attaching the rubber plug 11 into which the insulated wire 8 is inserted into the terminal cavity 7, the inside of the terminal cavity 7 is sealed waterproof so that water does not enter by the rubber plug 11.

  The rubber stopper 11 is made of a rubber material having elasticity such as silicone rubber. When the insulated wire 8 is inserted into the through hole 13 of the rubber plug 11, the covering material 10 of the insulated wire 8 and the rubber plug 11 are in close contact with each other so as not to leak water.

  The rubber plug 11 is formed to have a total length T in the through hole direction. Of the entire length of the rubber plug, a portion having a predetermined length Ta is formed as the high hardness portion 11A. The high hardness portion 11A is provided to provide the rubber plug with waterproof performance. The high hardness portion 11 </ b> A is formed to a hardness that can exhibit waterproof performance.

  The remaining length Tb of the rubber plug 11 is formed as a low hardness portion 11B. The low hardness portion 11B is formed with a lower hardness than the high hardness portion 11A. By providing the low hardness portion 11B with more flexibility than the high hardness portion 11A, the displacement due to vibration can be reduced, and the effect of preventing terminal wear can be improved.

  The waterproof hardness of the high hardness portion 11A in the rubber plug 11 means that the hardness is the same as that of a conventional rubber plug for waterproofing. That is, the high hardness portion 11A may be the same as or higher than the hardness of the conventional rubber plug. The specific hardness is preferably Hs50 or more. In addition, the hardness of this invention is the hardness measured with the spring type A type hardness tester by JISK6301 standard.

  The low hardness portion 11B of the rubber plug 11 may have a hardness lower than that of the high hardness portion 11A, but is preferably Hs40 or less. As the low hardness portion 11B becomes more flexible, the effect of improving the wear resistance by absorbing the vibration applied to the terminal and reducing the displacement is increased. The lower limit of the hardness of the low hardness portion 11B is preferably Hs30 or more from the viewpoint that the manufacturing is actually possible.

  The ratio of the length of the high hardness portion 11A and the low hardness portion 11B in the rubber plug is not particularly limited. That is, the length Ta of the high hardness portion 11A may be a minimum length that can exhibit the waterproof performance in the cavity. On the other hand, the length Tb of the low hardness portion 11B can exhibit vibration absorption performance as the length increases, and may be set as appropriate according to the size of the cavity space.

  Further, the positional relationship between the high hardness portion 11A and the low hardness portion 11B in the direction of the through hole 13 of the rubber plug 11 is not particularly limited. When the high hardness portion 11A is located on the outside of the cavity 7 and the low hardness portion 11B is located on the inside of the cavity 7, moisture entering the inside from the outside of the cavity 7 This is preferable because it can be reliably prevented by the high hardness portion 11A and good waterproof performance can be exhibited.

  The rubber plug 11 may be composed of a single rubber plug in which the high hardness portion 11A and the low hardness portion 11B are integrally formed, or the rubber plug 11 as a whole is configured as the high hardness portion 11A. You may comprise from several rubber plugs with the rubber plug 11 comprised as the hardness part 11B.

  When the high-hardness portion 11A and the low-hardness portion 11B are integrally formed with the rubber plug 11, even if they are integrally formed by two-color molding or are separately formed, they are joined with an adhesive or the like. Or may be integrated. Further, the rubber plug 11 has a high hardness portion 11A and a low hardness portion 11B each composed of a portion having a single hardness, but the high hardness portion 11A and the low hardness portion are respectively combined by combining a plurality of hardness portions. 11B may be configured.

  The rubber plug 11 may be composed of two or more types of hardness portions, and three or more types of hardness portions having different hardnesses. In the case of integrally molding a rubber plug in which three or more types of hardness parts are integrated, it can be formed by multicolor molding in a number corresponding to the number of each hardness part.

  In order to form the rubber plug 11 in the high hardness portion and the low hardness portion, the hardness can be adjusted as appropriate by changing the material of the rubber plug.

  When the rubber plug 11 is used in combination with a rubber plug made of the low hardness portion 11B and a rubber plug made of the high hardness portion 11A, the rubber plug 11 may be used between the rubber plugs even if they are used in close contact with each other. Either of them may be used so that a gap is formed.

  FIG. 3 is a sectional view showing another example of the waterproof connector of the present invention. As shown in FIG. 3, the waterproof connector 1 of the present invention may be configured by inserting a plurality of rubber plugs into a rubber plug 11 for one terminal cavity 7. In the example shown in FIG. 3, one terminal cavity 7 is composed of one rubber plug made of a high hardness portion 11 </ b> A and rubber plugs made of two low hardness portions 11 </ b> B and 11 </ b> B. These three rubber stoppers are mounted so as to be in close contact with each other.

  Note that the three rubber stoppers may be integrated by bonding with an adhesive or the like, or may be attached in a separate state. When the rubber plug 11 is composed of a plurality of rubber plugs, the rubber plugs 11 may be mounted with a gap between them.

  As shown in FIG. 3, the rubber plug of the low hardness portion 11B using a combination of a plurality of rubber plugs may have different hardness or may be formed with the same hardness. Further, the number of rubber plugs may be four or more.

  The upper limit of the total length T of the rubber plug 11 can be appropriately set within the range of the depth of the terminal cavity 7 in the electric wire longitudinal direction. In the total length T, it is possible to determine how much the ratio of the high hardness portion 11A and the low hardness portion 11B is to be made.

  Hereinafter, the hardness of the rubber plug and the vibration absorbing action of the connector will be described. When vibration is generated in an automobile equipped with a waterproof connector, the insulated wire 8 connected to the waterproof connector 1 is greatly shaken by the vibration. In such a case, a large load from the insulated wire 8 is transmitted to the housing 6 via the rubber plug 11. At this time, when the portion of the rubber plug 11 cannot suppress the load against the load input from the insulated wire 8, the load is directly applied to the male terminal 2 and the female terminal 4. When a load is applied to the male terminal 2 and the female terminal 4, a contact load is generated between the terminals 2 and 4, and the contact portions of the terminals 2 and 4 are worn.

  In general, if the length of the rubber plug is increased and formed to have a low hardness, the vibration absorbing effect is improved. However, when the rubber plug becomes flexible, the waterproof performance may be lowered. On the other hand, in the present invention, since the rubber plug 11 has the low hardness portion 11B, the vibration absorbing ability can be improved. Furthermore, since the rubber plug 11 has the high hardness part 11A, a sufficient waterproof performance can be secured. As described above, according to the present invention, both the waterproof property and the vibration absorbing property can be achieved by improving the vibration absorbing property without deteriorating the waterproofing property.

  FIG. 4 is an explanatory view showing a test method of the terminal displacement amount of the waterproof connector. The relationship between the hardness of the rubber plug 11 and the amount of terminal displacement was tested using the apparatus shown in FIG. The experiment measured how much the terminal side is displaced when a load is applied to the insulated wire side, assuming that when a vibration load is input from the insulated wire to the connector due to vibration, the connector terminal is moved. . Specifically, as shown in FIG. 4, the housing 6 is fixed in a state where the rubber plug 11 is mounted on the housing 6, a certain load is applied to the portion of the insulated wire 8 using a load meter 21, and the terminal The displacement amount of the portion 4 was measured with a laser displacement meter 22.

The rubber plug was prepared with a part having the same hardness as the conventional one and the hardness of the other part being changed. Specifically, as shown in FIG. 2 (b), one rubber plug having the same hardness as that of a conventional rubber plug and two rubber plugs having a changed hardness were used, for a total of three. The hardness of the part of the conventional rubber plug is Hs50, and the hardness of the part where the hardness is changed is Hs50 in Experimental Example 1, Hs30 in Experimental Example 2, Hs40 in Experimental Example 3, and Hs60 in Experimental Example 4, and the terminal displacement The amount was measured. The measurement results are shown in Table 1. Incidentally, the electric wire was used wire cross-sectional area 50 mm ^2.

  As shown in Table 1, when the relative displacement is set to 1 with reference to the experimental example 1 formed entirely in the same hardness as the conventional example, the displacement amounts of the experimental examples 2 and 3 in which the hardness change portion is set to low hardness, The amount of displacement was 0.88 and 0.96. This indicates that by providing the low hardness portion, the amount of displacement is reduced and a vibration suppressing effect can be obtained. On the other hand, in Experimental Example 4 in which the hardness change portion is made to have a high hardness, the displacement amount is larger than in Experimental Example 1, and the vibration suppressing effect is reduced.

The waterproof connector of the present invention can be suitably used as a waterproof connector for automobiles in a portion that is greatly subjected to vibration, such as a connector directly connected to an engine. In particular, it is effective for preventing wear of the terminal contact portion in the case of a waterproof connector for a high-voltage electric wire using an electric wire having a large wire diameter of 15 to 50 mm ² .

  As mentioned above, although the Example of this invention was described in detail, this invention is not limited to the said Example at all, In the range which does not deviate from the meaning of this invention, a various change is possible.

  For example, the rubber plug 11 of the above embodiment has a protrusion on the outer peripheral surface in contact with the housing, but the outer peripheral surface may be formed on a flat surface, or a recess may be formed. Moreover, the through-hole surface of the rubber plug 11 may be formed in unevenness, or may be formed in a flat shape without unevenness.

  The rubber plug 11 is made of silicone rubber in the above embodiment, but other rubber or the like may be used as long as it has elasticity and can secure waterproofness.

DESCRIPTION OF SYMBOLS 1 Waterproof connector 2 Male terminal 3 Male connector 4 Female terminal 5 Female connector 6 Housing 6a Male connector housing 6b Female connector housing 7 Terminal cavity 7a Male terminal cavity 7b Female terminal cavity 8 Insulated wire 9 Insulated wire conductor 10 Insulated wire covering material 11 Rubber plug 11A High hardness part 11B Low hardness part 13 Rubber plug through hole T Overall length Ta of rubber plug in the through hole direction Length of high hardness part of rubber plug Tb Length of low hardness part of rubber plug D Outside diameter of insulated wire G Outside diameter of rubber plug C Diameter of cavity

Claims (7)

A fitting terminal connected to the conductor of the insulated wire and a terminal cavity for housing the fitting terminal are provided in the housing, and a rubber plug into which the insulated wire is inserted is inserted into the inlet of the terminal cavity. A waterproof connector in which the inside of the terminal cavity is waterproofed by the rubber plug,
The rubber plug is a cylindrical body larger than the diameter of the inlet of the terminal cavity, has a through-hole having a size through which the insulated wire can be inserted, and has a hardness higher than that of the high hardness portion and the high hardness portion. The low-hardness part is formed in the area | region of the predetermined length of the said through-hole direction, The waterproof connector characterized by the above-mentioned.   The waterproof connector according to claim 1, wherein the high hardness portion and the low hardness portion are integrally formed in the rubber plug.   The waterproof connector according to claim 2, wherein the rubber plug has the high hardness portion and the low hardness portion integrally formed by multicolor molding.   The waterproof connector according to claim 2, wherein the rubber plug is formed integrally with the high hardness portion and the low hardness portion formed separately.   2. The waterproof connector according to claim 1, wherein the rubber plug is composed of a plurality of rubber plugs including a rubber plug having a high hardness portion and a rubber plug having a low hardness portion.   The waterproof connector according to any one of claims 1 to 5, wherein the hardness of the high hardness portion of the rubber plug is Hs50 or more.   The waterproof connector according to any one of claims 1 to 6, wherein the hardness of the low hardness portion of the rubber plug is Hs40 or less.

Images