EP0791985A1

EP0791985A1 - Saeled electrical connector

Info

Publication number: EP0791985A1
Application number: EP97102154A
Authority: EP
Inventors: Carlo Bertini; Aldo Bruni
Original assignee: Whitaker LLC
Current assignee: Whitaker LLC
Priority date: 1996-02-21
Filing date: 1997-02-11
Publication date: 1997-08-27
Also published as: GB9603632D0; KR970063826A; JPH09232030A

Abstract

An electrical connector (2) for terminating a wire (16), the connector having a connector body (4) with a forward mating end (10) and a rear wire receiving end (12) with a contact receiving passage way extending therebetween; a contact (14) positioned and retained in the contact receiving passageway where said contact (14) includes a forward contact portion (32) accessible from the mating end (10) of the connector body (4) and a rearward conductor engaging end (90) disposed toward the rear wire receiving end (12) of the connector body (4) for engaging the wire (16) such that the wire (16) trails outward of the connector (2) beyond the wire receiving (12) when terminated to the contact (14) and a seal (18) disposed within the connector body (4) having an outer sealing surface (20) forming a seal with the connector body (4) and an inner sealing surface (22) for forming a seal with a trailing wire (14); characterized in that a contact sleeve (30) is provided that includes at least a portion of the contact receiving passage way (56) therein where said sleeve (30) is constructed to receive the contact (14) so as to form a cartridge (36) where the cartridge (36) is insertable into the connector body (4) past the seal (18) along the inner sealing surface (22) thereof where it is then retained within the connector body (4).

Description

This invention relates to electrical connectors and in particular those electrical connectors requiring sealing along wires trailing therefrom in order to assure the electrical connection is sealed from contamination.
There are numerous applications in industry where it is necessary to assure that the electrical connection between mating contacts is reliably sealed from contamination. One particular application relates to automotive connectors where the connector may be disposed within the engine compartment and subject to contamination from road spray, combustion bi-products, and other elements that would be detrimental to a reliable electrical connection. The most common solution to this problem is to create a sealed capsule by way of the mating connectors such that a sealed unit is formed about the interconnection that extends from the wires entering a first connector half through to the wires exiting the second mating connector half. This may be accomplished in a variety of ways but typically a seal is provided between features of the mating connectors and then additional seals are provided along the wires that trail from the connector housings that further seal to the respective connector housings. The seal between the connector halves typically does not present any problems and may function similar to an O-ring where it is compressed between the two connector halves, as the connector halves remain relatively stationary to each other once mated. However, in some applications a problems does exist in assuring that a reliable seal is formed between the connector housing and the trailing wires as these trailing wires are subject to greater displacement relative to the connector housings.
One solution to the sealing problem is through the use of single wire seals that utilize an individual seal for each terminal. These seals are disposed about the trailing wire in a sealing manner and are received within a passageway of the connector body that corresponds to the passageway wherein the contact is disposed. Single wire seal is typically formed over resilient rubber-like material.
Another type of sealing that is commonly used, especially in high density applications, is a family-seal. An example of a family-seal is contained within US patent 4,629,269. This patent shows a connector housing having a plurality of contacts therein where wires trailing therefrom pass through openings in a family-seal. The contacts enter the connector by being pushed through the openings in the seal. In a family-seal there are a plurality of openings extending therethrough which the trailing wires extend. The family-seal includes an outer sealing surface that forms a seal to the connector body such that only a single seal element is required for forming the seal with multiple trailing wires. It is well known to also form the family-seal from a rubber-like material.
A problem with using the family seal is that the contacts upon which the wires are terminated typically have a larger effective cross section than the wires to which the seal is to be formed. While the material selected for the seal may have adequate physical properties to allow sufficient stretching of the material for the contact to pass therethrough and still form a seal along the trailing wire, the effective cross section of the contact is not the only consideration.
The contacts incorporated into modern electrical connectors have a number of features that may lead to damage of the seal as the contact passes therethrough. For example, a contact may include locking lances which are tongue-like projections extending outward from the contact body, polarization ribs may be formed to assure proper orientation of the contact within the connector or supporting back-up springs may be included that provide additional strength to the contact spring arms. In addition, all of these features and the basic contact may include sharp edges or abrupt transitions that could cause minor damage to the sealing surface through which the contact must pass. This is especially true when the sealing surface is stretched to allow the larger effective cross section of the contact to pass therethrough. What ultimately occurs is that small cuts are formed that reduce the effectiveness of the seal and possibly allow the contamination to enter the believed the to be sealed capsule.
One concept developed to improve upon the sealing of the trailing wires is to use a self-healing material, such as a gel-like substance, as the seal about the trailing wires. An example of this is described in US patent 4,662,692 where contacts having trailing wires terminated thereto are inserted through the gel like seal while the self-healing aspect of the gel-like material does assure that some of the damage caused by the contact passing therethrough is repaired, seals of this type may not be useful for all applications. In addition, the damage to the gel-like seal caused by the passing of a modern receptacle terminal may not be able to be fully healed by the self-healing nature of the material.
Therefore, a problem exists in that by inserting contacts, already terminated and having wires trailing therefrom through a seal, the passage of the contact may damage the seal. This damage ultimately deteriorates the effectiveness of the sealing along the trailing wire. What is needed is to assure that the sealing surface of the seal along the trailing wire is not damaged. In many cases it is not practical to simply insert the wire through the seal prior to termination upon the contact and therefore it is necessary to insert the contact through the seal.
In order to solve this problem of damage being caused to the seal, an electrical connector is provided for terminating a wire where the connector comprises a connector body having a forward mating end and a rear wire receiving end with a contact receiving passageway extending therebetween; a contact is positioned and retained in the contact receiving passageway where said contact includes a forward contact portion that is accessible from the mating end of the connector body and a rearward conductor engaging end for terminating the wire that is disposed toward the rear wire receiving end of the connector body so that the wire trails outward from the connector beyond the rear wire receiving end; and, a seal disposed within the connector having an outer sealing surface forming a seal with the connector body and an inner sealing surface for forming a seal along the trailing wire, where the electrical connector is characterized in that a smooth contact sleeve is provided that includes at least a portion of the terminal receiving passageway therein and is constructed to receive the terminal therein prior to insertion in order to form a cartridge and the cartridge being insertable into the connector body through the inner sealing surface of the seal the inner sealing surface where the cartridge is retained within the connector body.
It is an advantage of this invention that the smoothed sleeve protects the inner sealing surface as the cartridge is inserted into the connector body. It is another advantage of this invention that the sleeve may be formed of insulating material. It is yet another advantage of this invention that the wire may be terminated to the contact after the sleeve is disposed thereupon. It is still yet another advantage of this invention that the construction may be utilized with any of the aforementioned seal constructions.
The invention will now be described by way of example with reference to the drawings wherein:

Figure 1 is a cross sectional side view of a representational electrical connector according to the present invention;
Figure 2 is a top view of a sleeve according to the present invention incorporated into the connector of figure 1;
Figure 3 is a front end view of the sleeve of figure 2;
Figure 4 is a rear end view of the sleeve of figure 2;
Figure 5 is a cross sectional view of the sleeve of figure 2 taken along the line 5-5;
Figure 6 is a partial cross sectional side view of the sleeve of figures 2-5 seated upon a contact to form a cartridge that is incorporated into the connector of figure 1;
Figure 7 is a partial cross sectional side view similar to that of figure 6 showing an alternative cartridge construction in a first position;
Figure 8 is a partial cross sectional side view corresponding to the alternative embodiment of figure 7 showing the cartridge in a second position; and
Figure 9 shows an alternative construction of a contact having a protective sheath thereupon.

With reference first to figure 1, an electrical connector according to the present invention is representationaly shown at 2. The electrical connector 2 includes a connector body 4 having a main portion 6 and a nose portion 8. The connector body 6 includes a forward mating end 10 on the nose portion 8 and a rear wire receiving end 12 at the main portion 6. Disposed within the connector body 4 are contacts 14 that terminate wires 16 that trail outward from the connector 4 beyond the rear wire receiving end 12. Disposed along the connector body 4 is a seal 18. The seal includes an outer surface 20 that forms a seal with the connector body 4 and an inner surface 22 that forms a seal along the trailing wire 16. In this representation, the seal member 18 is a family seal having multiple inner surfaces 22 through which wire 16 trail. It is also envisioned that this invention could be used with single wire seals or seals constructed of material other than a rubber-like substance, such as silicon rubber. The seal member 18 is held in place by a retention plate 24 that overlies the seal 18 and is snapped into the main body 6 and retained therein by barbs 26 that are received in openings 28. This retention plate 24 may exert a compressive force upon the seal 18 to further enhance the sealing about the wires 16 and the connector body 4.
The contacts 14 are seated within a sleeve 30 in such a manner that a forward contact portion 32 of the contact 14 is accessible through openings 34 in the forward mating end 10 of the nose portion 8 of the connector body 4. The contact 14 has been seated in the sleeve 30 prior to inserting the contact into the connector body 4 as will be described in greater detail below. The contact 14 and the sleeve 30 form a cartridge unit 36 (see also figure 6) which is inserted into the connector body 4 and retained therein by resilient primary latching members 38 that deflect out of the way as the cartridge 36 passes thereby and then resile back such that a shoulder 40 thereupon is disposed behind and element of the cartridge 36 such that the cartridge 36 is prevented from being withdrawn from the connector body 4. There are numerous ways well known in the art of accomplishing this primary retention and any one of which could easily be incorporated into this design. In addition, to further assure that the cartridges 36 are properly positioned and prevented from being withdrawn a secondary locking member 42 is further included in the connector assembly 2 as is also well known in the art. In this representation, the secondary locking member 42 cooperates with the cartridge 36 along the sleeve 30 to prevent withdrawal. It would also be possible to have the secondary locking member 42 cooperate directly with the contact 14 of the cartridge 36 to assure contact retention and proper positioning. It would also be possible to have the nose portion 8 cooperate with the resilient latch arms 38 to assure that they are prevented from outward deflection after the cartridge 36 is properly seated in the connector body 4. This cooperation could also assure that the contacts 14 are properly seated within the connector body.
A mating connector (not shown) would be connected to this representational connector 2 from the front mating end 10 where male tab contacts would be received in the openings 34 to connect with the receptacle contacts 14. A shroud extending outward from the mating connector would be receiving over the nose portion 8 and the resilient arms 38 and into a cavity 44 existing between an annular lip 46 wherein a connector mating seal 48 is disposed this connector mating seal 48 prevents contamination from entering the connector pair where the connector halves physically mate. The seal 18 prevents contamination from entering along the trailing wire 16. The combination of the two seal members is designed to assure that there is no contamination at the interconnection between the receptacle contacts 14 and the mating contacts (not shown). As the present invention is concerned with primarily achieving an advantageous seal along the trailing wires, it should be apparent that other sealing constructions between mating connectors could be used as desired.
With reference now to figures 2-5, the sleeve 30 is described in greater detail. The sleeve 30 includes a forward end 50 and a rearward end 52 where a mating contact receiving opening 54 is provided at the forward end 50 and would correspond to the opening 34 and the mating end 10 of the connector body 4 (figures 1). The mating contact receiving opening 54 is in communication with a contact receiving passage way 56 that extends through the sleeve and is open at a contact receiving opening 58 in the rear end 52. The contact 14 is to be received within the passage way 56. The contact 14 is retained within the passage way 56 by a locking lug 60 having a stop shoulder 62 for cooperation with the contact to prevent withdrawal thereof, as best seen in figure 6. Extending inward from the rear end 52 are a pair of slots 64 that provide resilience to the plug 60 so that the contact may be inserted. With reference to figure 3, the sleeve 30 has a generally rectangular outer surface 66 formed of two pairs of opposing sides 70,72 that intersect through large blend radiuses 74 in order to provide a smooth surface to pass over the inner surface 22 of the seal 18. If it is desired to provide polarization features for the cartridge 36, the sleeve may include concave or convex surfaces 76 in one of the sides of the outer surface 66. These polarization features would also be smoothly blended in order to assure that no sharp edges exist that could possibly damage the seal 18. With reference to figure 2 and figure 5, it is also observed that where the forward end 50 and the rearward end 52 transition to the outer surfaces 66 blend radiuses 78 are provided. This radius 78 assures as the sleeve 30 is pressed through the openings in the seal 18 defined by the inner surfaces 22 there is no damage to the inner surfaces 22.
With reference now to figure 6, the cartridge 36 is shown. The cartridge 36 includes the sleeve 30 and the contact 14. The forward contact portion 32 includes 4 contact arms 80 extending from a body 82 to a nose 84. Each of the arms 80 include edges 86 therealong that are now contained within the shell 30. The body 82 further includes a rearward facing shoulder 88 that cooperates with the stop shoulder 62 of the latch 60 to assure that the contact 14 may not be separated from the sleeve 30. The contact 14 further includes a conductor engaging end 90 interconnected to the body 82 by a transition region 92. The conductor engaging portion 90 of the contact 14 is a crimp contact which includes a conductor engaging crimp 94 and a strain relief crimp 96 for reliably engaging and retaining the wire 16. With the sleeve 30 shown herein, the length of the sleeve is constructed such that when the contact 14 is seated therein the rear end 52 does not extend over the conductor engaging portion 90 so that the sleeve 30 could be placed upon the contact 14 prior to the contact 14 terminating the wire 16. This would enable the sleeve 30 to be attached while the contact 14 is still upon a carrier strip (not shown) advantageously using handling.
In addition, with reference now to figure 7 and figure 8, an alternative cartridge is shown generally at 136. The cartridge 136 comprises a contact 114 that is similar to the contact described above, but includes a resilient locking lance 101 for retaining the contact within the sleeve 130. The sleeve 130 is also generally configured as described above, but is slightly longer in length. The sleeve includes a first retention opening 103 and a second retention opening 105 that are constructed to cooperate with the retention lance 101 to establish a first and second position (figure 7 and figure 8 respectively). In the first position of figure 7, the conductor engaging portion 190 of the contact 114 is exposed from the sleeve 130. This enables the conductor (not shown) to be terminated while the sleeve 130 is still attached to the contact 114. Once the conductor has been terminated, the contact 114 is moved into the second position of figure 8 and the sleeve 130 fully overlies the contact including the conductor engaging end 190. This configuration may be particularly advantageous where such conductor engaging technology as insulation displacement contact is used.
With reference now to figure 1, the cartridge 36 is first constructed as shown in figure 6. The contact 14 has been inserted into the sleeve 30 and is retained therein by cooperation of the shoulder 88 on the contact 14 and the retention shoulder 62 on the latch 60 of the sleeve 30. The connector body 4 includes the seal member 18 positioned therein. The cartridge 36 is then inserted into the connector body 4 from the rear wire receiving end 12 such that the cartridge passes through the seal 18. As the cartridge 36 acts as a sheath over the corner edges 86 and the nose 84 of the contact 14 the inside sealing surface 22 is protected from damage. While the sleeve 30 does add to the effective cross section of the cartridge 36 this is accommodated by the resiliency of the sealing member 18. Once the cartridge has been asserted past the seal 18 and the resilient arms 38 the abutment surface 40 and the rear surface 52 of the sleeve 30 cooperate to retain the cartridge 36. Once fully seated, a secondary locking member 42 may be placed into the connector body 4 to further assure the contacts do not push back from their seated position. If the cartridge 36 were not fully inserted, the resilient latches 38 would not return to their normal position and it could be configured such that the secondary locking member 42 could not be inserted into the connector housing 4 as the passage way therefore would be blocked.
With reference now to figure 9 an alternative construction is shown. In this construction a cartridge 236 is formed that comprises a contact 214 having a protective sheath 230 formed upon the front portion at the contact 214. This protective sheath 230 is deposited directly upon the contact 214 by spraying, dipping or other procedures and is made of an epoxy or rubber-like compound, whereby the sharp edges are rounded thereby affording protection to the seal.
Advantageously then, an electrical connector is provided where the sealing member that forms a seal between the connector and the trailing wires is protected from damage by forming a cartridge having an outer protective sheath about the contact prior to inserting the cartridge through the seal. The sheath could be formed as a sleeve meter of insulating material that is fitted to the contact prior to insertion through the seal or an overcoating of an epoxy-like material that hardens in such a manner that smooths the edges of the contact so that a smoothed surface is provided.

Claims

An electrical connector (2) for terminating a wire (16), the connector comprising:
a connector body (4) having a forward mating end (10) and a rear wire receiving end (12) with a contact receiving passage way extending therebetween;

a contact (14) positioned and retained in the contact receiving passage way where said contact (14) includes a forward contact portion (32) accessible from the mating end (10) of the connector body (4) and a rearward conductor engaging end (90) disposed toward the rear wire receiving end (12) of the connector body (4) for engaging the wire (16) such that the wire (16) trails outward of the connector (2) beyond the wire receiving (12) when terminated to the contact (14) and;

a seal (18) disposed within the connector body (4) having an outer sealing surface (20) forming a seal with the connector body (4) and an inner sealing surface (22) for forming a seal with a trailing wire (14);

characterized in that a smoothed surface contact sheath (30,230) is provided about the contact (14) where said sheath (30) and the contact (14) form a cartridge (36) that is insertable into the connector body (4) past the seal (18) along the inner sealing surface (22) where it is then retained within the connector body (4).
The electrical connector of claim 1, further characterized in that the sheath (30) is a plastic sleeve that includes at least a portion of the passageway and an outer surface having smoothly blended transitions.
The electrical connector (2) of claim 2, further characterized in that the sheath (30) extends over the forward contact portion (32) of the contact (14).
The electrical connector (2) of claim 3, further characterized in that the sleeve extends over the conductor engaging end (90).
The electrical connector (2) of any one of claims 1-4 further characterized in that a secondary locking member is provided.
The electrical connector (2) of any one of claims 1-5, further characterized in that the electrical connector includes multiple contacts individually received in separate cartridges and the seal is a family seal having multiple inner sealing surfaces corresponding to each of the wires trailing from the multiple contacts.
The electrical connector of claim 1, further characterized in that the sheath is an overcoating of epoxy-like material.