Charger locking mechanism

A locking mechanism for locking a first member that is inserted into a second member into a first member, such as to secure an inductive coupler in a charge port while it is used to charge an electric vehicle. The locking mechanism prevents premature or malicious removal of the coupler before charging has been completed. The locking mechanism has logic that allows a user to set the lock in the charge port prior to insertion of the coupler. The locking mechanism has an actuator coupled to a rotatable link that is rotated thereby. A first pin is coupled to the rotatable link and a hole disposed in the first member that mates with the first pin to lock the inductive coupler in the charge port. A spring loaded release mechanism coupled to the first pin that permits the first pin to slide into the hole. Motion of the cable and the release mechanism releases and locks the first pin in the hole, or retracts the first pin from the hole, thus locking and unlocking the locking mechanism.

BACKGROUND 
The present invention relates generally to locking mechanisms, and more 
particularly, to a locking mechanism for use with an inductive charger. 
The assignee of the present invention designs and manufactures inductive 
charging systems for use in charging electric vehicles. The charging 
system employs a charge port into which an inductive coupler is inserted 
to charge the electric vehicle. It has been determined that there is a 
need for a locking mechanism that secures the inductive coupler in the 
charge port during the charging process. There is no known prior art for 
such a locking mechanism. 
Although there have not been any previous inductive coupled chargers built 
with a locking feature, there have been other designs developed by the 
assignee of the present invention that grabbed the coupler from the side 
at locations where tactile feel and EMI indents are located. This approach 
has tolerance problems, and does not solidly lock the coupler in place. 
Accordingly, it is an objective of the present invention to provide for a 
locking mechanism that locks a first member that is inserted into a second 
member. It is a further objective of the present invention to provide for 
a locking mechanism that secures an inductive coupler in a charge port of 
an inductive charger during charging. 
SUMMARY OF THE INVENTION 
To meet the above and other objectives, the present invention is a locking 
mechanism for locking a first member that is inserted into a second 
member. More particularly, the locking mechanism may be used to secure an 
inductive coupler in a charge port while it is used to charge an electric 
vehicle. The locking mechanism prevents premature or malicious removal of 
the coupler before charging has been completed. The locking mechanism has 
logic that allows a user to set the lock in the charge port prior to 
insertion of the coupler. This is accomplished with a simple push pull 
motion of a lock actuator. 
More particularly, the locking mechanism comprises a lock actuator that is 
coupled to a rotatable link by a cable that is used to rotate the 
rotatable link. A first pin is coupled to the rotatable link, and is 
caused to slide laterally as a result of motion of he rotatable link. A 
hole disposed in the first member is designed to mate with the first pin 
to lock the first member in the second member. A spring loaded release 
mechanism is coupled to the first pin that locks the pin in an "armed" 
position and then permits it to slide into the hole when it is disengaged. 
Motion of the cable and release mechanism thus releases and locks the 
first pin in the hole or retracts the first pin from the hole, thus 
locking and unlocking the locking mechanism. 
The lock actuator may be a motor or solenoid, for example. The locking 
mechanism may comprise a pin delay mechanism that cooperates with a 
compression spring, a fixed bracket or stop, and two cable stops to insert 
the first pin in and remove the first pin from the hole. The first pin 
comprises a groove, and the spring loaded release mechanism may comprise a 
torsion spring, a lever arm coupled to the torsion spring that has a slot 
that mates with the groove in the first pin, and a second pin extends from 
the lever arm and engages a slot a the first member and that pushes the 
second pin to rotate the lever arm out of the groove in the first pin, 
thus permitting the first pin to slide into the hole. The pin delay 
mechanism thus delays the motion of the first pin into the hole by locking 
it into a firing position prior to actuation of the release mechanism.

DETAILED DESCRIPTION 
Referring to the drawing figures, FIGS. 1a and 1b show top and side views, 
respectively, of a portion of an inductive charging system 10 employing a 
locking mechanism 20 in accordance with the principles of the present 
invention. In FIG. 1b, the charging coupler 12 is partially inserted into 
the charge port 11. FIGS. 2a and 2b show views of the locking mechanism 20 
wherein the charging coupler 12 is fully inserted into the charge port 11. 
FIGS. 3a and 3b show views of the locking mechanism 20 illustrating cable 
movement to unlock it. 
The inductive charging system 10 includes a charging coupler 12, coupler 
paddle 12, or first member 12 (shown in FIGS. 1b and 1c) that is inserted 
into a charge port 11, or second member 11 (shown in FIG. 1a), to initiate 
charging of an electric vehicle (not shown). FIG. 1c is a perspective view 
of the inductive coupler 12 used in the present invention. The charging 
coupler 12 forms a primary of a transformer while the charge port 11 forms 
the secondary thereof. Once the charging coupler 12 is inserted into the 
charge port 11, power is transferred from a power source (not shown) to 
propulsion batteries of the electric vehicle under control of a controller 
(not shown). 
Referring to FIG. 2, the inductive coupler 12 comprises a plastic housing 
12a that has two mating coupler halves 12b, 12c that are configured to 
provide a handle 12d. The inductive charging coupler 12 has a center 
ferrite puck 12e and a primary winding (not shown) disposed around the 
puck 12e. With reference to the present invention, the coupler 12 includes 
an opening 23a or holes 23a and coupler stops 23b that are employed to 
lock it into the charge port 11. Conductive plastic strips 12f are 
disposed along an exterior portion of the coupler 12 that engage 
metallized electromagnetic interference (EMI) fingers (not shown) on the 
charge port 11 when the coupler 12 is inserted into the charge port 11. 
The locking mechanism 20 has a first pin 21 that cooperates with one of the 
holes 23a in the coupler paddle 12 (depending upon its orientation during 
insertion) to lock it in the charge port 11. The first pin 21 is coupled 
to a rotatable link 26 that rotates about a fixed axis 26a in response to 
motion of a cable 24 and a spring loaded pin delay mechanism 40. The 
rotatable link 26 is coupled to one end of the pin delay mechanism 40, 
which is used to arm the first pin 21 prior to its release into the hole 
23a. The rotatable link 26 enables lateral motion of the first pin 21 
relative to the motion of the cable 24 and moves the pin 21 into an armed 
position. 
The spring loaded pin delay mechanism 40 comprises a small portion 24a of 
the cable 24 that is coupled at a first end to the rotatable link 26. The 
small portion 24a of the cable 24 is inserted through a hole in a fixed 
bracket 43a, and through the center of a compression spring 42, and is 
coupled to a cable end flange 43b formed as a cylindrical cup. The small 
portion 24a of the cable 24 has a first retaining member 44a or retaining 
clip 44a secured thereto adjacent its first end that prevents it from 
being pulled through the fixed bracket 43a. One end of a large portion of 
the cable 24 has an enlarged end or head 44b that forms a second cable 
stop 44b. The second cable stop 44b is captivated within the cable end 
flange 43b by a second retaining member 44c or retaining clip 43c that 
engages an internal groove of the cable end flange 43b. The second cable 
stop 44b and second retaining clip 43c keeps the cable 24 from pulling out 
of the cable end flange 43b. An opposite end of the large portion of the 
cable 24 is connected to a lock actuator 25 (FIG. 1a), which may be 
provided by a motor or solenoid, for example. The lock actuator 25 is used 
to pull or push the cable 24 to lock and unlock the locking coupler paddle 
12 in the charge port 11. 
The spring loaded pin delay mechanism 40 is used to arm the first pin 21 
prior to its insertion into the hole 23a in the coupler paddle 12, and to 
remove the first pin 21 from the hole 23a. Motion of the cable 24 and 
rotatable link 26 in one direction arms the first pin 21 which is 
subsequently released and inserted into the hole 23a upon operation of the 
spring loaded release mechanism 22 thus locking the locking mechanism 20. 
Motion of the cable 24 and rotatable link 26 in the opposite direction 
retracts the first pin 21 from the hole 23a, thus unlocking the locking 
mechanism 20. 
The spring loaded release mechanism 22 comprises a lever arm 28 that is 
spring loaded by a torsion spring 29, and the lever arm 28 has a slot 36 
therein (FIG. 2b) that mates with the groove 27 (FIG. 2a) in the first pin 
21 when the pin is armed. During arming, the compression spring 42 is 
compressed against the fixed bracket 43a by motion of the large portion of 
the cable 24 toward the rotatable link 26. The first pin 21 is moved 
laterally by this action until the slot 36 in the lever arm 28 mates with 
the groove 27 in the pin 21. A second pin 31 extends laterally from the 
lever arm 28 and engages the coupler stop 23b in the coupler paddle 12. 
When the coupler paddle 12 is fully inserted into the charge port 11, the 
coupler stop 23b pushes the second pin 31 which rotates the lever arm 28 
out of the groove 27 in the first pin 21, thus permitting the first pin 21 
to slide into the hole 23a. 
The hole 23a in the coupler paddle 12 secures the first pin 21 after the 
locking mechanism 20 is released. The first pin 21 is inserted in the hole 
23a so that the coupler paddle 12 is locked in the charge port 11 with 
left to fight symmetry. The coupler stop 23b is used to stop the movement 
of the coupler paddle 12 and is also cooperates with the release mechanism 
22 by moving the lever arm 28 out of the groove 27 in the first pin 21, 
which allows the first pin 21 to slide into the hole 23a. The hole 23a in 
the coupler paddle 12 are surrounded by overhangs 33, 34 (FIG. 1c) that 
limit the distance the coupler paddle 12 can be inserted in to the charge 
port 11. The coupler paddle 12 has left-to-right symmetry and the pin 21 
may be inserted into either hole 23a, depending upon the orientation of 
the coupler paddle 12. 
The locking mechanism 20 uses the overhang 34 on the second pin 31 to 
activate it when the coupler paddle 12 is inserted into the charging port 
11. The locking mechanism 20 is first set by pushing against the link 26. 
This action causes retraction of the first pin 21. The spring loaded lever 
arm 28 is connected to the torsion spring 29 and falls into the groove 27 
in the first pin 21 when the pin 21 is fully retracted. This retains the 
pin 21 so the coupler paddle 12 can be inserted without any interference. 
When the coupler paddle 12 reaches the bottom of the charging port 11, the 
lever arm 28 is pushed down on one side by the overhang 34 on the second 
pin 31 and slot 32 in the coupler paddle 12. This action releases the 
first pin 21 if the rotatable link 26 is allowed to move. This can only be 
done when the cable 24 or actuator 25 has been pulled (or pushed) to allow 
motion of the rotatable link 26. 
The logic associated with operation a reduced-to-practice embodiment of the 
locking mechanism 20 is that pushing the cable 24 or actuator 25 unlocks 
the first pin 21 and sets the locking mechanism 20; pulling the cable 24 
or actuator 25 allows the first pin 21 to lock the coupler paddle 12 upon 
insertion into the charging port 11 and actuation of the release mechanism 
22. The logic may be reversed by causing the rotatable link 26 to unlock 
when it is pulled and lock when it is pushed. 
Space constraints originally dictated the design of the preferred 
embodiment of the locking mechanism 20 in that it was not possible to use 
an actuator 25 that was located directly in line with the first pin 21, 
which would eliminate the rotatable link 26. 
Thus, a locking mechanism that secures the inductive coupler in the charge 
port during the charging process has been disclosed. It is to be 
understood that the above-described embodiment is merely illustrative of 
some of the many specific embodiments which represent applications of the 
principles of the present invention. Clearly, numerous and varied other 
arrangements may be readily devised by those skilled in the art without 
departing from the scope of the invention.