JP2003331979A - Waterproof connector and rubber plug for sealing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent a rubber plug for sealing from slipping off a cavity without any cost hike. <P>SOLUTION: In a state where the rubber plug for sealing 30 is inserted into the cavity 12, liquid trying to infiltrate inside the cavity 12 through an eyehole 33 is held back by a filter 35. A pressure inside the cavity 12 is maintained almost at an atmospheric pressure by the filter 35, the rubber plug for sealing 30 is prevented from being pushed out of the cavity 12 due to difference of pressure between the inside and the outside of the cavity 12. Since there is no need of providing a locking component in a separate body for holding the rubber plug 30 inside the cavity 12, its cost can be held down low. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a waterproof connector.

[0002]

2. Description of the Related Art As a waterproof connector, a plurality of cavities are formed in a housing, a waterproof rubber stopper is fixed to the rear end of a terminal fitting, and the terminal fitting and the rubber stopper are inserted into the cavity to form a rubber connector. There is known a structure in which the outer periphery of the stopper is in close contact with the inner periphery of the cavity for waterproofing. In this type of waterproof connector, a common housing is used even when the number of poles is different. However, in a usage mode in which the number of poles is small, there is an empty cavity into which the terminal fitting is not inserted. If this empty cavity is left as it is, water or foreign matter may enter the housing through the empty cavity. Therefore, a waterproof sealing rubber plug is attached to the empty cavity instead of the rubber plug.

As this rubber stopper for sealing, an oil-containing rubber material is used for the purpose of enhancing the mountability in the cavity similar to a commonly used rubber stopper. With this sealing rubber plug made of an oil-containing rubber material, the frictional resistance with the inner peripheral surface of the cavity is reduced, so it is possible to insert the sealing rubber plug securely into the cavity even with a small pushing force. You can

[0004]

In the waterproof connector, when the housings are fitted to each other, the fitting surface of the housings is also sealed. Therefore, the waterproof connector has a space formed between the housings and each of the spaces communicating with the space. The pressure in the cavity rises, and as a result, a force is exerted on the sealing rubber plug in the direction of pushing it out of the cavity. However, as described above, the sealing rubber plug is made of an oil-containing rubber material in order to reduce the frictional resistance with the cavity.Therefore, the pressure increase in the cavity causes the sealing rubber plug to be pushed out of the cavity. There was a risk of being lost.

As a means for preventing the sealing rubber plug from coming off the cavity, as disclosed in Japanese Utility Model Laid-Open No. 3-74482, a pin-shaped member is fixed to the sealing rubber plug, There is one in which the pin-shaped member is locked to the resin lance in the cavity. However, since this sealing rubber plug is composed of two parts, the rubber plug body and the pin-shaped member, there is a problem that the cost is high. The present invention has been made in view of the above circumstances, and an object thereof is to provide a means for preventing the sealing rubber plug from coming off from the cavity without increasing the cost.

[0006]

According to a first aspect of the invention, a housing having a cavity into which a terminal fitting is inserted through an insertion opening, and an empty cavity in which the terminal fitting is not inserted are inserted. By that,
A waterproof connector comprising a sealing rubber stopper for restricting entry of foreign matter into the empty cavity, wherein the sealing rubber stopper is deep inside the empty cavity when inserted into the empty cavity. Side and the insertion port side are formed with through holes, and the through holes are provided with a filter having air permeability and capable of restricting the flow of liquid.

According to a second aspect of the present invention, in a waterproof connector in which a terminal fitting is inserted from an insertion opening into a cavity formed in a housing, the terminal fitting is inserted into an empty cavity in which the terminal fitting is not inserted. Is a sealing rubber plug that restricts the entry of foreign matter into the empty cavity, and has a through hole that is open to the inner side of the empty cavity and the insertion port side when inserted into the empty cavity. The through hole is provided with a filter having air permeability and capable of restricting the flow of liquid.

[0008]

[Operation and effect of the invention] [Invention of claim 1 and 2] When the sealing rubber plug is inserted into the empty cavity, the liquid from the outside of the cavity tries to enter into the cavity through the through hole. However, the ingress of the liquid is blocked at the filter. Also, even if the internal pressure of the empty cavity begins to rise, the air in the cavity is discharged to the outside of the cavity through the filter,
Atmospheric pressure inside empty cavity (pressure outside housing)
Is maintained at about the same pressure as. Therefore, the sealing rubber plug is prevented from being pushed out of the cavity due to the pressure difference between the inside and the outside of the cavity. Further, since it is not necessary to provide a separate locking component for holding the sealing rubber plug in the cavity, the cost can be kept low.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] A first embodiment of the present invention will be described below with reference to FIGS. First, the male connector M to which the waterproof connector A of the present embodiment is fitted will be described.
Is a hood portion Mb projecting forward from the connector body Ma, and a plurality of tabs Mc at the front end of the male terminal fitting (not shown) housed in the connector body Ma are provided in the hood portion Mb. The book is protruding. Then, the waterproof connector A of the present embodiment is fitted in the hood portion Mb.

The waterproof connector A includes a housing 10 made of synthetic resin, a female terminal fitting 20 housed in the housing 10, and a sealing rubber plug 30 mounted as required.
And is configured. A ring-shaped seal member 11 is mounted on the outer periphery of the housing 10. When the housing 10 is fitted into the hood portion Mb, the seal member 11 is brought into close contact with the outer peripheral surface of the housing 10 and the front end portion of the hood portion Mb. Therefore, the housing 10 and the hood portion Mb
The gap between and is sealed in a liquid-tight manner.

A plurality of cavities 12 having a resin lance 13 and an opening at a rear end portion (right and left end portions in FIGS. 1 and 2) serving as an insertion opening 14 are formed in the housing 10. The terminal fitting 20 is inserted into each cavity 12 from the insertion port 14, and the inserted terminal fitting 20 is retained by the locking of the resin lance 13. The first half region of the inner wall of the cavity 12 in which the resin lance 13 is provided is formed in a substantially rectangular cross section. On the other hand, the cavity 12
The rear end side portion (that is, the portion close to the terminal insertion port 14) of the inner wall of is shaped in a circular cross section, and the inner peripheral surface of this circular portion becomes the mirror-finished sealing surface 15. There is.

The terminal fitting 20 is inserted into the cavity 12 through the insertion opening 14, and the box-shaped fitting portion 21 at the front end thereof is locked to the resin lance 13 so that the terminal fitting 20 is held in the retaining state. There is. Then, the hood portion M of the male connector M with the terminal fitting 20 inserted to the normal position.
When the waterproof connector A is fitted to b, the tab Mc in the hood portion Mb is inserted into the box-shaped fitting portion 21 of the terminal fitting 20 and is electrically connected.

An open barrel-shaped electric wire crimping portion 22 is formed at the rear end of the terminal fitting 20, and the electric wire crimping portion 22 is liquid-tight with respect to the front end of the electric wire 23 and the outer periphery of the electric wire 23. The front end portion of the terminal rubber plug 24 that is externally fitted to the terminal is crimped. The terminal rubber plug 24 is made of an oil-containing rubber material, and a plurality of (three in the present embodiment) lip portions 25 extending in the circumferential direction are formed on the outer periphery of the lip plug 25 at intervals in the front-rear direction. . The outer diameter of the lip portion 25 is larger than the inner diameter of the sealing surface 15.

The sealing rubber plug 30 is made of an oil-containing rubber material like the terminal rubber plug 24, and has a circular shape as a whole. On the outer periphery of the sealing rubber plug 30, the terminal rubber plug 2 is provided.
Similar to 4, a plurality of (three in the present embodiment) lip portions 31 are formed at intervals in the front-rear direction. Size of each lip 31 (width dimension in the front-rear direction, and outer diameter dimension)
And the front and rear pitches between the lip portions 31 are the rubber plugs for terminals 2
The size is set to be the same as that of the lip portion 25 of No. 4. On the rear end surface of the sealing rubber plug 30, a cylindrical finger contact portion 32 having an outer diameter smaller than that of the lip portion 31 is concentrically formed so as to project.

A circular through hole 33 is provided inside the sealing rubber plug 30 and a front end surface of the sealing rubber plug 30 and the finger contact portion 3.
2 is formed in a concentric manner while penetrating substantially linearly so as to open to the rear end surface of the second member. On the inner circumference of the through hole 33, a circumferential recessed portion 3 is formed by cutting out a substantially central position in the front-rear direction (a position corresponding to the central lip portion 31).
4 are formed, and the filter 35 is provided in the recess 34.
The outer peripheral edge of is fitted. The inside of the through hole 33 is divided into front and rear by the filter 35. Filter 3
5 has a circular shape as a whole, and a cylindrical pin receiving portion 36 extending rearward is formed on the outer peripheral edge thereof, and the pin receiving portion 36 is fitted into the recess 34 of the through hole 33. Have been combined. The filter 35 is made of a material that is breathable and blocks the passage of liquid. An example thereof is a porous synthetic resin material (for example, PTFE) having a large number of pores (not shown) each having a size smaller than a water droplet and larger than a molecule of water vapor (for example, about 0.2 micron). To be Further, examples of products include “GORE-TEX (registered trademark)” and the like.

The filter 35 is preformed in a form having a predetermined thickness so as not to be easily deformed, and the sealing rubber plug 30 is formed by insert molding when the sealing rubber plug 30 is molded. It is integrated with. When molding the sealing rubber plug 30, a mold 40 is used as shown in FIGS. 5 and 6. The mold 40 is composed of an upper mold 41 and a lower mold 42. In the lower mold 42, a molding space 43 for molding the outer surface shape of the sealing rubber plug 30 and an axis line of the sealing rubber plug 30 are vertically arranged. It is formed so as to open upward in the direction of the direction. Further, in the molding space 43, a holding pin 44 having an outer circumference serving as a molding surface for molding the rear end side portion of the inner circumference of the through hole 33 is projected upward. On the other hand, the upper mold 41
Has a lid shape that closes the opening of the molding space 43 of the lower mold 42, and a molding pin 45 for molding the front end side portion of the inner periphery of the through hole 33 projects from the lower surface thereof. .

At the time of molding, first, the filter 35 is placed on the upper end portion of the holding pin 44. At this time, as shown in FIG. 5, the pin receiving portion 36 is fitted on the outer periphery of the holding pin 44, and thus the filter 35 is held on the upper end portion of the holding pin 44. After this, the upper die 41 is lowered to move the lower die 4
6, the molding space 43 is closed as shown in FIG. 6, and the melted rubber (not shown) is filled in the molding space 43.
Inject. Then, after the rubber has solidified, the upper mold 41 is raised and the molded sealing rubber plug 30 is removed from the lower mold.

Next, the operation of this embodiment will be described. When the terminal fitting 20 is not inserted into the cavity 12, a sealing rubber plug 30 is inserted into the empty cavity 12 for waterproofing. At the time of insertion, the finger tip is directed to the finger contact portion 32 at the rear end portion of the sealing rubber plug 30 and pushed. During the insertion process, the lip portion 31 of the sealing rubber plug 30 slides while closely contacting the inner peripheral surface of the cavity 12 while being elastically deformed. The insertion work is completed when the sealing rubber plug 30 is inserted to a position where the finger contact portion 32 is completely accommodated in the cavity 12 (the state shown in FIG. 1). In this state, all the lip portions 31 elastically come into close contact with the sealing surface 15, whereby a liquid-tight seal is provided between the outer circumference of the sealing rubber plug 30 and the inner circumference of the cavity 12. At the same time, the sealing rubber plug 30 is held in the cavity 12 so as not to move back and forth.

When the connectors A and M are fitted in this state, the fitting portion of the connectors A and M is sealed.
While being sealed by 1 to be sealed in an almost airtight state, the volume of a slight space formed between the connectors A and M decreases with the fitting. As a result, the pressure in the cavity 12 starts to rise, but the air in the cavity 12 is discharged to the outside of the cavity 12 through the filter 35 and the through hole 33, so that the inside of the empty cavity 12 is at atmospheric pressure (of the housing 10). External pressure) is maintained at about the same pressure. Therefore, it is possible to prevent the sealing rubber plug 30 from being pushed out of the cavity 12 due to the pressure difference between the inside of the cavity 12 and the outside of the cavity 12. Therefore, the sealing rubber plug 30 remains in the cavity 12.

Further, in the state where the sealing rubber plug 30 is inserted into the empty cavity 12, even if the liquid tries to enter into the cavity 12 from the outside of the cavity 12 through the through hole 33, the penetration of the liquid is a filter. Blocked at 35. As described above, in the present embodiment, the sealing rubber plug 30 is formed with the through hole 33 that opens to the inner side of the cavity 12 and the insertion port 14 side while being inserted into the empty cavity 12. , This through hole 33
In addition, since the filter 35 having air permeability and capable of restricting the flow of liquid is provided, it is not necessary to provide the sealing rubber plug 30 with a separate locking component for holding it in the cavity 12. It is possible to reduce the cost.

[Other Embodiments] The present invention is not limited to the embodiments described above with reference to the drawings. For example, the following embodiments are also included in the technical scope of the present invention. In addition to the above, various modifications can be made without departing from the scope of the invention. (1) In the above embodiment, the filter is integrated with the sealing rubber plug by insert molding, but according to the present invention,
The filter and the sealing rubber plug may be preformed as separate parts and assembled together. In this case, the filter can be assembled by forming a recess on the inner circumference of the through hole and elastically expanding and deforming the sealing rubber plug.

(2) In the above embodiment, the filter is located so as to correspond to the lip portion in the front-back direction, but according to the present invention, the filter may be arranged at a position separated from the lip portion. (3) In the above-described embodiment, the filter is arranged at a substantially central position of the through hole, but according to the present invention, it may be arranged at a position near the end of the through hole. (4) In the above embodiment, the sealing rubber plug has a front-back asymmetric shape, but according to the present invention, the sealing rubber plug may have a front-back symmetrical shape.

(5) In the above embodiment, only one filter is provided for one sealing rubber plug, but according to the present invention,
A plurality of filters may be provided on one sealing rubber plug. (6) In the above-mentioned embodiment, one through hole is provided in one sealing rubber plug.
However, according to the present invention, a plurality of through holes may be provided in one sealing rubber plug, and a filter may be provided in each through hole. (7) In the above-described embodiment, the through hole is formed so as to penetrate straight through. However, according to the present invention, one end of the through hole is opened to the end surface of the rubber stopper for sealing and the other of the through holes is formed. The end may be opened to the outer peripheral surface of the sealing rubber plug, and the through hole may be formed into an L shape as a whole.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a state in which a sealing rubber plug is inserted into an empty cavity in Embodiment 1.

FIG. 2 is a cross-sectional view of the sealing rubber plug in a state where it is inserted into an empty cavity.

FIG. 3 is a cross-sectional view of the sealing rubber plug removed from the cavity.

FIG. 4 is a sectional view showing a state in which the terminal fitting is inserted into the cavity.

FIG. 5 is a sectional view showing a mold opening state of a mold for molding a sealing rubber plug.

FIG. 6 is a cross-sectional view showing a clamped state of a mold for molding a sealing rubber plug.

[Explanation of symbols] A ... Waterproof connector 10 ... Housing 12 ... Cavity 20 ... Terminal fittings 30 ... Rubber stopper for sealing 33 ... through hole 35 ... Filter

Claims (2)

[Claims] 1. A housing having a cavity into which a terminal fitting is inserted through an insertion opening, and a foreign material intruding into the empty cavity by being inserted into an empty cavity in which the terminal fitting is not inserted. And a sealing rubber plug that regulates a sealing rubber plug, wherein the sealing rubber plug includes a sealing rubber plug on a back side of the cavity and a side of the insertion opening in a state of being inserted into the empty cavity. A waterproof connector characterized in that a through hole is formed, and a filter having air permeability and capable of restricting liquid flow is provided in the through hole. 2. A waterproof connector in which a terminal fitting is inserted from an insertion opening into a cavity formed in a housing, by inserting the terminal fitting into an empty cavity in which the terminal fitting is not inserted, the empty cavity A rubber plug for sealing that restricts foreign matter from entering the inside, wherein a through hole that opens to the inner side of the empty cavity and the insertion port side is formed in the empty cavity. Is a rubber stopper for sealing, which is provided with a filter having air permeability and capable of restricting the flow of liquid.