JPH07263074A - Waterproof rubber stopper - Google Patents

Abstract

(57) [Abstract] [Purpose] The bending force that acts on the wire protection tube of the waterproof rubber plug that is in close contact with the wire causes deformation of the wire protection tube and a series of intermediate tubes, resulting in poor sealing performance. To prevent [Structure] An electric wire 1 inserted through an electric wire insertion hole on an inner peripheral side, a terminal crimping tubular portion 5 which is tightened and fixed to a terminal 9, and
An intermediate cylinder portion 6 which is connected to the rear end portion of the terminal crimping cylinder portion 5 and which is provided with a sealing annular projection 16 which is in close contact with the inner peripheral surface of the wire insertion passage 15, and a rear end portion of the intermediate cylinder portion 6. And an electric wire protection cylinder portion 7 that is continuous and closely fits to the outer coating 18 of the electric wire 1,
At the connecting portion between the intermediate tubular portion 6 and the wire protection tubular portion 7, the intermediate tubular portion 6 communicates with the electrical wire protection tubular portion 7.
The outer peripheral surface of the rear end outer peripheral portion 36 separated by the buffer groove 37
Is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a waterproof rubber plug which is water-tight between a wire connected to a terminal and attached to a wire insertion passage of a connector housing so as to be watertight.

[0002]

2. Description of the Related Art An automobile wire harness or the like is connected to a lead wire or the like of an electric device or the like via a connector. However, when a connection point between the connectors is expected to allow raindrops or the like to enter from the outside. , The connector must be waterproofed. As a waterproofing method, there are a simple type in which the entire connector has a waterproof structure, or a waterproof rubber plug attached to each electric wire unit is used to draw in the electric wire insertion passage of the connector housing.

FIGS. 4 and 5 show a conventional example of a waterproof rubber plug 2 attached to an electric wire 1 and a waterproof structure of a connector 3 using the waterproof rubber plug 2. This waterproof rubber plug 2 is disclosed in Japanese Utility Model Laid-Open No. 63-3074, and as shown in FIG. 4, is made of rubber or the like having a substantially tubular shape having an electric wire insertion hole 19 through which the electric wire 1 can be inserted. Is integrally formed, and is functionally provided with three parts of a terminal crimping tubular portion 5, an intermediate tubular portion 6, and an electric wire protecting tubular portion 7. Here, the terminal crimping tubular portion 5 is a tubular portion that is fastened and fixed by the crimping piece 10 of the terminal 9 (see FIG. 5) together with the inserted electric wire 1, and is a thin portion that is fastened by the crimping piece 10. The diameter portion 11 and an enlarged diameter portion 12 located at the front end of the small diameter portion 11 for preventing the caulking piece 10 from coming off the tightening portion are configured.

Further, the intermediate tubular portion 6 is provided so as to be continuous with the rear end portion of the terminal crimping tubular portion 5, and the wire insertion passage of the connector housing 14 when inserted into the connector housing 14 on the outer peripheral surface thereof. It is a tubular portion provided with a plurality of sealing annular projections 16 that are in close contact with the inner peripheral surface of 15. Further, the electric wire protection tubular portion 7 is a thin tubular portion which is continuous with the rear end portion of the intermediate tubular portion 6 and which is tightly fitted to the outer coating 18 of the inserted electric wire 1. In the case of this example, the terminal 9 is a so-called male terminal, and a caulking piece 10 for caulking and crimping the small diameter portion 11 of the waterproof rubber plug 2 together with the electric wire 1 on the base end side, and a conductor of the electric wire 1. 21 by crimping the wire 1
And a pressure-bonding piece 22 that is electrically connected to. Further, the distal end portion 23 connected to the base end portion is a tongue-shaped protruding piece that projects from the terminal accommodating chamber 17 communicating with the wire insertion passage 15 and is electrically connected to the female terminal.

When the waterproof rubber plug 2 constructed as described above is attached to the electric wire 1 connected to the terminal 9 and inserted into the electric wire insertion passage 15 of the connector housing 14, the terminal 9 is inserted into the terminal accommodating chamber 17. By being engaged with the flexible locking piece (lance) 25 provided on the rear side so as not to be pulled out backward, it is mounted in the wire insertion passage 15. In this mounted state, the waterproof rubber plug 2 is preferably waterproofed by the sealing annular projection 16 pressing against the inner peripheral surface of the wire insertion passage 15 to make the wire 1 and the connector housing 14 watertight. Was given.

[0006]

At this point, the electric wire 1 pulled out from the connector 3 is placed at a location where the connector 3 is arranged (for example,
It may be bent appropriately depending on the restrictions (in the engine room) and the wiring situation of the electric wire 1. In that case, waterproof rubber stopper 2
As shown in FIG. 6, the electric wire protection cylinder portion 7 closely fitted to the electric wire 1 is also bent. As a result, in the conventional waterproof rubber plug 2, the bending force acting on the electric wire protection tubular portion 7 due to the bending of the electric wire protection tubular portion 7 reaches the intermediate tubular portion 6, and as shown in FIG. The sealing annular projection 16 on the side extending by bending is separated from the inner peripheral surface of the wire insertion passage 15 to form a gap 27 between the wire insertion passage 15 and the connector housing 14 and the waterproof rubber plug 2. There was a problem that the sealing performance deteriorated. In other words, in order to ensure a predetermined sealing performance, the electric wire 1 drawn out from the connector 3 must be fixed or the connector 3 must be positioned so that no bending force is applied to the electric wire protection cylinder portion 7. In order to secure a predetermined sealing performance, there is a problem that the degree of freedom in wiring the electric wires is impaired.

The present invention has been made in view of the above circumstances,
The electric wire pulled out from the connector bends from the wiring,
Even if a bending force is applied to the wire protection cylinder that holds the wires in close contact, the waterproof rubber stopper deformation caused by this bending force does not extend to the intermediate cylinder that secures the sealing performance. By providing a rubber stopper, the intrusion of water can be reliably prevented and the reliability can be improved without lowering the adhesion between the sealing annular projection of the intermediate cylinder and the inner peripheral surface of the wire insertion passage. , The purpose is to increase the degree of freedom in wiring.

[0008]

A waterproof rubber stopper according to the present invention for achieving the above object comprises a terminal crimping tubular portion, an intermediate tubular portion, and a thin wire protective tube along an electrical wire insertion hole for inserting an electrical wire. A tubular waterproof rubber plug that sequentially has a portion and that seals between the electric wire and the electric wire insertion passage by inserting the electric wire into the electric wire insertion passage of the connector housing. It is characterized in that a rear end outer peripheral portion is formed so as to be separated from the outer peripheral surface of the portion with a buffer groove interposed therebetween and to be closely fitted to the inner peripheral surface of the electric wire insertion passage. And
The waterproof rubber plug may be characterized in that a buffer groove is provided on the entire circumference of the electric wire protection cylinder portion.

[0009]

[Function] Since the electric wire protection cylinder portion and the rear end outer peripheral portion are separated in the radial direction by the buffer groove, a double structure is provided.
Even if the wire protection cylinder that holds the wires in close contact is bent, the bending force that acts on the wire protection cylinder is absorbed by the buffer groove and does not reach the rear end outer circumference. Continue to hold the state of tight fitting on the inner circumference side of the wire insertion passage.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the waterproof rubber stopper according to the present invention will be described in detail below with reference to the drawings. FIG. 1 is a perspective view showing a connector structure to which a waterproof rubber plug according to an embodiment of the present invention is applied, FIG. 2 is a vertical cross-sectional view of the waterproof rubber plug, and FIG. The same parts as those of the conventional structure are designated by the same reference numerals and the description will be simplified.

The connector 3 has a connector housing 14 made of a synthetic resin having an excellent insulating property, and an appropriate number of terminal accommodating chambers 17.
(Two chambers in FIG. 1) are arranged in a line, and at positions near the tips in the respective terminal accommodating chambers 17, the male terminals 9 inserted into the respective terminal accommodating chambers 17 are engaged so that A lance 25 is provided to prevent the terminal 9 from slipping out behind. In the connector 3, the waterproof rubber plug 30 attached to each electric wire 1 connected to each terminal 9 provides waterproofing in electric wire units in the connector housing 14.

As shown in FIG. 2, the waterproof rubber plug 30 has a substantially tubular shape as a whole into which the electric wire 1 can be inserted, and is formed as an integrally molded product such as synthetic rubber.
Functionally, the terminal crimping tubular portion 5, the intermediate tubular portion 6, and the electrical wire protecting tubular portion 7 which are sequentially provided along the electric wire insertion hole 19 on the inner peripheral side.
And three parts. Here, the terminal crimping cylinder portion 5
Is the terminal 9 together with the electric wire 1 inserted through the electric wire insertion hole 19.
2 is a tubular portion that is tightened and fixed from the outside by the crimping piece 10 (see FIG. 1), and as shown in FIG. And an enlarged diameter portion 12 located at the front end of the caulking piece 10 for preventing the caulking piece 10 from coming off the tightening portion.

Further, the intermediate tubular portion 6 is a terminal crimping tubular portion 5.
It is a tubular portion that is continuous with the rear end portion and that has annular sealing projections 16 provided at three locations on the outer peripheral portion at regular intervals. The outer diameter of the sealing annular projection 16 is set so as to be in close contact with the inner peripheral surface of the wire insertion passage 15 communicating with the terminal accommodating chamber 17, and the expanded diameter portion 12 of the terminal crimping tubular portion 5 is in contact. Greater than.

The electric wire protection cylinder portion 7 is provided continuously to the rear end portion of the intermediate cylinder portion 6, and is a thin-walled cylindrical portion which is closely fitted to the outer coating 18 of the electric wire 1 inserted through the electric wire insertion hole 19. Is. Then, the connecting portion between the intermediate tubular portion 6 and the electric wire protection tubular portion 7 communicates with the intermediate tubular portion 6, and is separated from the outer peripheral surface of the electrical wire protection tubular portion 7 with the buffer groove 37 interposed therebetween. A rear end outer peripheral portion 36 is provided. The rear end outer peripheral portion 36 is provided such that the outer peripheral surface thereof is closely fitted to the inner peripheral side of the wire insertion passage 15. In the present embodiment, the buffer groove 37 is provided with a substantially U-shaped cross section, and is formed over the entire circumference of the connecting portion between the intermediate tubular portion 6 and the wire protection tubular portion 7. Further, the rear end outer peripheral portion 36 of the intermediate tubular portion 6 has a thin-walled cylindrical shape, and at the end portion thereof, a flange-shaped flange portion 38 for position regulation that abuts the opening edge of the electric wire insertion passage 15. Has been formed.

The waterproof rubber plug 30 has an electric wire insertion hole 19 through which the electric wire 1 is inserted together with the outer coating 18 of the terminal caulking tubular portion 5, the intermediate tubular portion 6, and the electrical wire protective tubular portion 7. The electric wire insertion hole 19 is set such that the inner diameter thereof is smallest in the electric wire protection cylinder portion 7, and a plurality of concave and convex portions are formed along the inner peripheral surface. ing. With such a structure, the waterproof rubber plug 30 simultaneously achieves the contradictory functions of the insertability and the adhesiveness of the electric wire 1.

In the case of this example, the terminal 9 is a so-called male type terminal, and at the base end side thereof, there is a crimping piece 10 for gripping the small diameter portion 11 of the waterproof rubber plug 30 into which the electric wire 1 is inserted. , A crimping piece 22 for crimping the conductor 21 of the electric wire 1 to electrically connect to the electric wire 1, and a tip portion 23 connected to the base end portion is fitted to the tip of the female terminal. It is a tongue-shaped protrusion.

In crimping the terminal 9 to the electric wire 1, first, the tip of the electric wire 1 with the outer cover 18 attached is penetrated into the electric wire insertion hole 19 of the waterproof rubber plug 30, and the waterproof rubber plug 30 is inserted. From the terminal crimping cylinder part 5 of
Is performed with the tip of the stub protruding. Next, the outer coating 18 on the tip side of the electric wire 1 is peeled off to expose the conductor 21, and the waterproof rubber plug 30 is placed so that the exposed conductor 21 comes to the position of the crimping piece 22 of the terminal 9. The terminal 9 is vertically attached to the terminal crimping tubular portion 5 and the conductor 21 protruding from the terminal crimping tubular portion 5. Then, the crimping piece 10 is crimped first to mechanically fix the terminal 9 to the waterproof rubber plug 30 and the electric wire 1, and then the crimping piece 22 is crimped to electrically connect the conductor 21 and the terminal 9. Connecting.

When the terminal 9 thus connected to the tip of the electric wire 1 is inserted to the prescribed position of the terminal accommodating chamber 17 of the connector housing 14, the lance 25 engages with a predetermined portion of the terminal 9. At the same time that the terminal 9 is prevented from coming off from the rear, the waterproof rubber plug 30 is press-fitted into the electric wire insertion passage 15, and the sealing annular protrusion 16 is tightly fitted to the inner peripheral surface of the electric wire insertion passage 15. Connector housing 1
4 and the waterproof rubber plug 30 are waterproofed. Also,
The electric wire protection cylinder portion 7 is brought into close contact with the outer coating 18 of the electric wire 1, so that waterproofing between the waterproof rubber plug 30 and the electric wire 1 is also realized.

By the way, the waterproof rubber plug 30 constructed as described above has a form in which the electric wire protection cylinder portion 7 and the rear end outer peripheral portion 36 of the intermediate cylinder portion 6 are radially separated by the buffer groove 37. Therefore, the bending force applied to the wire protection cylinder portion 7 acts so as to be absorbed by the buffer groove 37, and is not transmitted to the rear end outer peripheral portion 36 of the intermediate cylinder portion 6.

In fact, the electric wire 1 pulled out from the connector 3
When a bending force acts on the wire and the wire protection tube portion 7 of the waterproof rubber plug 30 that is in close contact with the wire 1 bends, as shown in FIG. 3, the buffer groove 37 on the side extending by bending is a groove. Since the width of the buffer groove 37 on the side of widening and contracting is narrowed,
The electric wire protection tubular portion 7 is allowed to bend and the electric wire protection tubular portion 7
The bending force acting on the intermediate cylinder portion 6 is prevented from being transmitted to the intermediate cylinder portion 6 side. Therefore, even when a bending force acts on the wire protection cylinder portion 7, the wire protection cylinder portion 7 and the series of intermediate cylinder portions 6 are not deformed due to the bending force, and the sealing annular projection 16 is formed. It is possible to prevent a decrease in adhesion between the wire and the inner peripheral surface of the wire insertion passage 15. As a result, it is possible to increase the degree of freedom in wiring and the like without lowering the predetermined sealing performance.

In the above embodiment, the rear end outer peripheral portion 3
At the rear end of the electric wire insertion passage 15, there is provided a flange portion 38 that abuts against the opening edge of the electric wire insertion passage 15, and since the flange portion 38 enhances the close contact with the electric wire insertion passage 15, the bending of the electric wire protection tubular portion 7 is performed. It is possible to further reduce the influence of. Further, the specific structure of the connector 3 in which the waterproof rubber plug 30 of the present invention is used and the structure of the terminal 9 are not limited to those of the above embodiment.

Further, in the above embodiment, the buffer groove 3 is provided over the entire circumference of the connecting portion between the intermediate tubular portion 6 and the wire protection tubular portion 7.
7 is formed, but if the direction in which the wire protection tubular portion 7 is bent is clear due to the mounting position of the connector 3, etc.,
For example, the buffer groove 37 may be divided into two sides, that is, a side that extends by bending and a side that contracts by bending, and each may be a semicircular groove, or a plurality of pieces may be provided by being finely divided. However, in the point that the buffer groove 37 prevents the bending force acting on the electric wire protection cylinder portion 7 from being transmitted to the intermediate cylinder portion 6 side, it is preferable that the cushion groove 37 has a shape that extends over the entire circumference as in the above embodiment. desirable. Although not described in detail in the above embodiment, as shown in each drawing, by forming the electric wire protection tubular portion 7 rearward with respect to the rear end outer peripheral portion 36, a long shape is obtained. The electric wire protection cylinder portion 7 can sufficiently follow the bending of the electric wire 1 to achieve close fitting with the electric wire 1.

[0023]

As described above, according to the waterproof rubber plug of the present invention, the space between the electric wire protection cylinder portion and the rear end outer peripheral portion of the intermediate cylinder portion is radially separated by the buffer groove formed in the connecting portion. Since the bending force applied to the electric wire protection cylinder is not directly transmitted to the rear end outer peripheral portion of the intermediate cylinder, the intermediate cylinder is prevented from being separated from the wire insertion passage. Therefore, even when the wire pulled out from the connector is bent and a bending force acts on the wire protection tube of the waterproof rubber plug, the wire protection tube and a series of intermediate tubes are deformed due to this bending force. It never happens. As a result, the annular protrusion of the intermediate tubular portion can prevent a decrease in the adhesion with the inner peripheral surface of the wire insertion passage, and thus increase the degree of freedom in wiring, etc. without lowering the predetermined sealing performance. It will be possible.

[Brief description of drawings]

FIG. 1 is a partially cutaway perspective view of a connector to which a waterproof rubber stopper according to the present invention is applied.

FIG. 2 is a vertical sectional view of a waterproof rubber stopper according to an embodiment of the present invention.

FIG. 3 is an operation explanatory view of the waterproof rubber stopper according to the embodiment of the present invention.

FIG. 4 is a vertical sectional view of a conventional waterproof rubber plug.

FIG. 5 is a vertical sectional view of a conventional connector using a waterproof rubber stopper.

FIG. 6 is an explanatory view of the operation of a conventional waterproof rubber plug.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 electric wire 3 connector 5 terminal crimping tubular portion 6 intermediate tubular portion 7 electric wire protecting tubular portion 9 terminal 10 crimping piece 11 narrow diameter portion 12 expanded diameter portion 14 connector housing 15 electric wire insertion passage 16 sealing annular projection 17 terminal accommodating chamber 19 Electric wire insertion hole 30 Waterproof rubber plug 36 Rear end outer peripheral portion 37 Buffer groove 38 Flange portion

Claims (2)

[Claims] 1. A terminal crimping tubular portion, an intermediate tubular portion, and a thin electrical wire protective tubular portion are sequentially provided along an electrical wire insertion hole through which an electrical wire is inserted,
A tubular waterproof rubber stopper that seals between the electric wire and the electric wire insertion passage by inserting the electric wire into the electric wire insertion passage of the connector housing. The waterproof rubber plug communicates with the intermediate tubular portion and cushions the outer peripheral surface of the electric wire protection tubular portion. A waterproof rubber plug, characterized in that a rear end outer peripheral portion is formed which is separated by sandwiching the groove and which is closely fitted to the inner peripheral surface of the electric wire insertion passage. 2. The waterproof rubber plug according to claim 1, wherein the buffer groove is provided on the entire circumference of the wire protection cylinder portion.