Electrical connector

An electrical connector (1) comprising a first conenctor section (3) for connection to an electricity conducting means, and a second connector section (2) communicating with the first connector section (3), the second connector section (2) including at least two arms (5, 6) extending therefrom, each of the arms have a transverse engagement surface (8), the transverse engagement surface (8) of one of the arms being substantially parallel to the trasverse engagement surface (8) of the other of the arms and defining a contact surface for engagement with an electrical terminal.

The invention relates to electrical connectors in particular the type 
adapted for connection of leads to spark plugs, coils and distributor caps 
of internal combustion engines. 
Traditionally, connection of a lead to a spark plug or coil has comprised a 
cylindrical connector which fits over and surrounds a spark plug or coil 
terminal. Such connectors are usually encased in elastomeric material to 
allow limited movement of the connector whilst maintaining a substantially 
water-tight seal about the spark plug or coil terminal. Therefore, it is 
necessary to accurately locate the terminal within the cylinder. This has 
been difficult to achieve where the connector is recessed well within the 
elastomeric material. 
The cylindrical connector is usually encircled by a partial cylindrical 
spring clip which serves to reinforce the connection of the cylinder to 
the terminal. One example of this type of connector is disclosed in 
Australian patent 502,552 which comprises additional semi-cylindrical 
spring material with locating lugs to ensure positive engagement about the 
terminal of a spark plug. Spark plugs in current engines are commonly 
recessed and in view of the limited finger space it is not possible for 
disconnection to be accomplished by pulling about the end of the 
connector. 
Thus to disengage the conventional electric connector assembly, one needs 
to pull upon the elastomeric boot or lead and, therefore, cause tension 
between the connector and the lead where they join. Consequently the 
connection between the connector and the lead can deteriorate causing 
intermittant electrical transfer with well-known consequences upon the 
ignition of the engine. 
It is proposed according to a first aspect of the invention that the 
connector section need be neither cylindrical nor require close axial 
engagement of the connector and terminal. 
Accordingly there is provided an electrical connector comprising a first 
connector section for connection to an electricity conducting means, and a 
second connector section communicating with the first connector section, 
the second connector section including at least two arms extending 
therefrom, each of the arms have a transverse engagement surface, the 
transverse engagement surface of one of the arms being substantially 
parallel to the transverse engagement surface of the other of the arms and 
defining a contact surface for engagement with an electrical terminal. To 
enable firm location of the terminal by the transverse engagement 
surfaces, they are preferably separated by a distance less than the 
transverse dimension of the terminal. 
Preferably the engagement surfaces lie in a common plane normal to the arms 
and are pressed down and about the terminal. In view of the substantially 
parallel nature of the engagement surfaces the terminal may be located at 
any point therebetween avoiding the precise connection techniques 
characteristic of cylindrical connectors. As the terminal is not totally 
encircled by the connector there is no need for accurate alignment with 
the centre line of the surrounding boot of elastomeric material. This 
arrangement also assists disengagement of the connector from the terminal 
by angular motion minimizing the tension exerted upon the connection 
between the terminal and the lead. 
Typically the oppositely disposed engagement surfaces are ribs or ridges. 
Overall in the second connector section the arms may project normal to the 
base to form a channel of general U-shaped appearance. The base of the 
second connector section may also serve as a positive limit to the 
terminal to prevent it being over inserted and to give the user a positive 
feel when the terminal is totally engaged. 
The orientation of the engagement surfaces relative to the remaining 
portion of the connector may be varied for convenient lead connection, the 
important requirement being that those surfaces in use present traversely 
of the terminal. Similarly the actual shape of the surfaces can be varied 
providing they can firmly engage the terminal. 
In a second aspect of the invention an improvement is provided in the known 
conventional connector of the type described above and illustrated in 
Australian patent 502,552. Accordingly an electrical connector is provided 
comprising a first connector section for connection to an electricity 
conducting means and a second connector section comprising a base section 
and a pair of arms extending from the base section, the base section and 
pair of arms defining a generally cylindrical shaped surface for engaging 
an electrical terminal, the base section including an open ended slot 
extending longitudinally of the base section. 
Preferably, a reinforcement means substantially surrounds the second 
connector section and biases the pair of arms towards one another and 
holds the terminal tightly when inserted within the connector. To enhance 
this, the reinforcement means may be fabricated to resilient material such 
as spring material. 
It has been found that the provision of this longitudinal open ended slot 
allows additional flexing about the terminal and reduces stress in the 
connector when a terminal is engaged or disengaged. 
This additional flexing allows accommodation of both the J.I.S. and 
S.A.E./ISO standard terminals and permits easier axial engagement of the 
terminal thereby minimizing the risk of damage to the terminal and 
insulation elastomeric boot surrounding it during the engagement and 
disengagement operation. 
In a third aspect of the invention there is provided an electrical 
connector comprising a first connector section for connection to an 
electricity conducting means, a second connector section for connection to 
an electrical terminal and stop means interposed between the first 
connector section and second connector section, the stop means defining a 
limit to which the electricity conducting means is locatable in the first 
connector section towards the second connector section. 
Conventionally, connection to the lead is achieved by placing the 
electricity conducting means, e.g. a lead, within a pair of flanged arms 
provided on the first connector section. After location of the lead these 
arms are crimped together to positively engage the connector to the lead. 
As indicated the improvement comprises the formation of a stop means 
interposed between the first connector section and the second connector 
section. This defines the end surface to which the lead can be inserted 
between the arms. It has been found the provision of such a stop means 
protects the electricity conducting means from physical damage, 
cross-arcing damage, increases the interface between the electricity 
conducting means and the terminal and also assists in the control of 
assembly lengths of cable in which form the electricity conducting means 
is usually available. 
The stop means may be integrally formed from the connector by punching part 
of the material to be upstanding. This is easily achieved by a stamping 
operation where the terminal is of metallic material. 
The stop means may be incorporated into conventional connector assemblies 
or to be used in combination with either of the first and second aspects 
of the invention described above.

Referring to FIGS. 1 through 6 a connector assembly 1 is provided 
comprising a terminal connector end 2 and a lead receiving end 3. 
Terminal connector end 2 is of approximately U-shape as shown in FIG. 5 and 
has a base 4 and arms 5 and 6. In base 4 is an upstanding lug 7. Arms 5 
and 6 each have an inward bent section 8 forming a channel way 9. Bent 
sections 8 run approximately parallel to one another. 
Lead receiving end 3, as shown in FIG. 3, comprises a pair of arms 10 and 
11 having corrugations 12 running thereon. Stop 13 is formed from the 
assembly 1 and is approximately 90.degree. to the longitudinal axis of 
assembly 1. 
In use, a lead (not shown) is inserted between arms 10 and 11. The lead 
abuts lug 13. Thereafter arms 10 and 11 are crimped towards one another 
securely locating the lead therebetween. 
Whilst also not shown the terminal connector end 2 is encased in 
elastomeric material with channel way 9 communicating with an aperture 
formed in the elastomeric material. 
When connecting this connector assembly to a spark plug, the terminal of 
the spark plug is inserted in the aperture in the elastomeric material and 
the terminal presented to channel way 9 approximately normal to the bent 
sections 8. The length of bent sections 8 is large compared with the 
cross-section dimension of the terminal giving a large insertion area. 
Thus avoids the tight axial alignment characteristic of prior art 
terminals. As the terminal is of cross-sectional dimension greater than 
the distance between bent sections 8, pushing the terminal connector end 
down the terminal passes it through channel way 9 towards base 4. Lug 7 
ensures the terminal is located in its optimum position. Bent sections 8 
in the fully inserted terminal position locate upon ridges formed in the 
terminal thereby securing it into position. To disengage the terminal from 
the connector assembly it is not necessary to pull the connector assembly. 
Rather by angular deflection of the connector relative to the terminal, 
the terminal forces bent sections 8 to open outwardly allowing 
disengagement. 
The second aspect of the invention is illustrated in FIGS. 7 to 10 in which 
like features to those shown in FIGS. 1 to 6 are given like numbers. 
Further it entails the same lead connection to assembly 14 as in FIGS. 1 
to 6. 
Terminal connector end 15 is provided with a cylindrical portion 16 and a 
surrounding tension clip 17 surrounding. Cylindrical portion 16 has an 
opening 18 along its entire length and a longitudinal slot 19 oppositely 
disposed to opening 18. A pair of dimples 20 impose into the terminal 
receiving cavity 21. 
In use the terminal (not shown) is aligned with cylindrical portion 16 and 
inserted into terminal receiving cavity 21. The initial dimension of the 
terminal is larger than that of the cylindrical portion 16, and as it is 
inserted, cylindrical portion 16 flexes outward expanding slot 19, opening 
18 and clip 17. The terminal is inserted until dimples 20 locate in a 
corresponding recess on the terminal. 
The provision of longitudinal slot 19 relieves stress in cylindrical 
portion 16 which increases the durability of the connector assembly and 
gives a minimal change in terminal entry and withdrawal force for given 
change in terminal diameter.