Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
CA 02232266 1998-03-17
A SYSTEM FOR LOCKING FILLER CAPS
Field of the Invention
The present invention refers to a lock system for the
filling caps of closed tanks, especially those tanks
containing inflammable liquids such as the fuel tanks
of service (gas) stations.
Backaround of the Inven~ion
Fuel supply to service stations takes place upon the
arrival of the transporting tanker truck, when each
tank of said service stations is opened.
The filling is achieved by removing the filling cap at
the feeding nozzle of the fuel tank, which opens
toward the surface of the service station and through
which a suitable conducting element, such as a hose,
is introduced, providing a temporary fluid
communication between the reservoir of the tanker
truck and the tank of the service station. The removal
of the filling cap is achieved by the easy opening of
a conventional padlock, which hinders the movement of
the cap lock arms and retains the cap against the
nozzle of the tank.
Due to the easy access to the inside of the service
station tanks, resulting from the precarious closing
system thereof, the contents of said reservoirs are
. liable to composition adulterations, such
adulterations being difficult to prove.
One solution for this problem is to provide the tank
filling caps with closing and locking systems which
are electrically activated at well determined time
- periods. Nevertheless, said solution cannot be applied
to fuel tanks, due to the danger of explosion caused
by electrical sparks, which may occur in this type of
lock systems.
Moreover, even though the electrically activated
systems present the most elaborate closures in the
~ S~
~ - CA 02232266 1998-03-17
' ' ' ;
state of the art _he~.~ are 5~ill easily ac=:---= by
conventional elec~rl~ sonnectors, which lea--e ..c =~ace
of having had the tank cap removed at times x~ . are
not solely for the purpose of supplying the tan~
Disclosure of the Invention
Thus, it is an object of the present in e.l~ic~. to
provide a lock system for the filling caps o_ c osed
tanks which can deny access to the inside o said
tanks between supply periods of time.
Another object of the present invention is _o p- -- de
a lock system such as that cited above, which ;~o-s not
pose risks, as for example explosions, _o those
environments in which said reservoirs to be loc~e~ are
located.
These and other objectives are reached throuGh a lock
system for the filling caps of closed tar.ks,
especially those tanks containing inflammable iicuids,
said cap comprising: a body seated over the respec_ive
tank nozzle and articulating at least one lock arm,
bearing a respective lock which can be displaced
between the locking and releasing positions in
relation to the nozzle, when there is a corresponding
angular movement of the lock arm, said system fur~ner
comprising an arm activating assembly- provided in the
cap body and including a drive shaft, mountea a~:ially
on the cap body in a freely rotating manner and ha~ing
an end which is accessible on the outside of the cap
and to which a torque tool is selectively applied: at
least one impelling piston, mounted axially through
the cap body, so that one outer end may be coupled to
the lock arm and the opposite inner end to the filling
cap, each impelling piston being axially d apl a-ed
between a first position corresponding to the lock arm
locking position and a second position corresDond~ng
to the lock arm releasing position; at leas~ one
electromagnetic clutch, mounted to the cap body a~ as
,0
CA 02232266 1998-03-17
3 .,~' .
.
to cause the selective axial displacement of the
impelling piston between the first and second
operational limit positions thereof when the drive
shaft rotates, said clutch comprising a coupling
means, which is displaced between an engaging
position, in which the rotation of the drive shaft
causes the axial displacement of the impelling piston
and a disengaging position, in which the drive shaft
rotates freely upon torque application; at least one
coil means coupled to the cap body, so as to cause,
when energized, the displacement of the coupling means
toward the engaging position; an electronic switch
provided with a transformer primary (L1) energized at
low power and coupled to a transformer secondar- (L2)
mounted on the cap body, so as to induce in the
transformer secondary (L2) enough current to
operationally energize the coil means of the
electromagnetic clutch.
Brief Description of the Drawinas
The invention will be described below, based on the
attached drawings, in which:
Fig. 1 schematically illustrates a filling cap
according to the present invention, which is mounted
onto the tank nozzle in the closed cap position and in
the open cap position (dashed lines);
Fig. 2 schematically illustrates the cap of figure 1
in an open state and provided with the lock system of
the present inventioni
Fig. 3 is a schematic top plan view of the filling cap
of the present invention;
Fig. 4 schematically illustrates a lock pin provided
in the cap body;
Fig. 5 is a block diagram of the closure system of the
present inventioni
Fig. 6 illustrates an electronic circuit associated to
0
CA 02232266 1998-03-17
the block diagram of figur- 5 and proviced -n ~he
filling cap; and
Fig. 7 illustrates an electronic circuit associat-d to
the block diagram of figure 5 and provided -~-ith an
electronic switch.
Best Mode for CarrYinq Out the Invention
According to the figures presented, the lock system of
the present invention comprises a filling cap 10 for
the closure of a feed nozzle 20, which is disposed at
an upper wall portion of a tank (not illust_ate~) and
which is constructed under the surface of a service
station. Said feed nozzle 20 presents an access end
20a facing said surface and an opposite end (not
illustrated), facing the inside of the reser-~oir. ~he
access end 20a is in the form of a body, -~hich
projects from a recessed portion of said surface and
which is concentric to said nozzle, the profile of
which being defined so as to receive and retain the
filling cap lO. The height of the projecting portion
of said access end 20a over the lower surface of said
recess is such that, in the tank closed position, the
filling cap 10 is substantially coplanar ~-ith the
surface of the service station.
The filling cap 10 is "T" shaped, having a cap bod~ 11
of the closed and substantially cylindrical type and
bearing, at one end, a head portion 12, from -~hich
peripheral edge there is downwardly projected a
peripheral skirt 13 wllereto there is mounted, in a
suitable manner, such as by tempered pins P, at least
one, but preferably a pair of lock arms 14, -~-hich are
diametrically opposite to each other and mounted to
the peripheral skirt 13, by means of the respective
articulated end 14a. The opposite end 14b or each of
said lock arms 14 is mounted to a corresponding
impelling piston 15 of an arm activating ass~mbly,
which is axially displaced through the inside o_ the
~ CA 02232266 1998-03-17
~ , . . .
cap body 11 between a first position corresponding to
the lock arm locking position and achieved by the
~ engagement of a locking portion of each lock arm 14 to
the tank feed nozzle, and a second position
corresponding to the lock arm releasing position. In
the preferred construction, lock arms 14 may also be
in a partially open state. The assembly of the
opposite end 14b of each lock arm 14 to the respective
impelling piston 15 takes place by the sliding fit of
a guide pin 16, which is provided at a free end 15a of
each said impelling piston 15 and which projects from
a side wall of said piston, orthogonally to the axis
thereof~ Said guide pin 16 is engaged in a lateral
slot 14c, preferably a through slot, which is axially
defined at the opposite end 14b of each said lock arm
14 and through which each said guide pin 16 slides
when there is an opening or a closing movement of
filling cap 10.
In the illustrated construction, the cap body 11 is
closed at one of the ends thereof, by a bottom cap 17
supporting in its face internal to said cap body 11 a
supporting base 18 of the lock system of the present
invention, to be described later~
When in the locking position, an enga-ging portion 14d
at the articulated end 14a of each lock arm 14 fits
into a restricted annular region 21 of the pro~ecting
end of the feed nozzle 20, until the opening of the
filling cap 10 has been commanded, when the movement
of each impelling piston 15 withdraws said engaging
portions 14d, unlocking said filling cap 10 from the
feed nozzle 20.
Each impelling piston 15 further presents an opposite
end 15b, which is internal to the cap body 11 and
which is affixed by a pinion 30 internally screwed on
and which acts in the opening and closing movements of
the filling cap 10~ ,~
- ' CA 02232266 1998-03-17
.-, . ;;;
According to the present ~..--ention, the arm ~ ing
assembly further includes, mounted on the -ns ~e of
cap body 11, an electrcmagnetic clutch 'A'h'~'l, -.ihen
activated by an electronic activating s..-irch 40
mounted on a tanker truck, nOt illustrated, -aus-s the
selective axial ~isplacement of the impell nc piston
15, between the first and second operational pcsi~ions
thereof and allows for the opening and closins of said
filling cap 10. The electronic switch 40 is -o~ered by
the tanker tank battery by means of suitable cables C
and connected to the filling cap 10 in an enaaaing
portion 10a thereof and upon the openinc of s2id
fillirlg cap 10 is maintained in this s.a~e of
connection until the closure of said fillinc cap 10
has been effected. The electronic switch 40 is
programmed, so that after a determined a-~e~aae ime
interval for the filling operation has elapsed, it de-
energizes the filling cap 10, avoiding the replace~ment
thereof in the reservoir nozzle. In this sta~e, onl- a
technician can reinstate normal use conditions. Said
electronic activating switch 40 comprises a
transformer primary L1 energizable at low ?o-,:er; at
least one manual activating button 42, by -..hich the
operator can command the end of the open or closed
states of the filling cap 10 when, for any reason, the
electronic switch 40 detects the filling cap 10 to be
in a partially open state; and at least one audio
visual signal 43, which indicates to the operator the
end of the opening or closing operations of Ihe
filling cap 10, obtained by a command from Ihe
electronic switch 40 or when its coupling =~ said
filling cap 10 has not been accomplisnec. The
electronic activating switch 40 includes at leas_ one
electromagnetic communicating element, pre~erab'~,- a
first optic transmitter Tl and a first optic ~ecepror
Rl, which communicate respectively with a seccnc o~-_ic -i
;;' ' ''
~ CA 02232266 1998-03-17
~ ~ .....
.
7 . ' . .,.~
.
receptor R2 and a second optic transmitter T2 provided
in the engaging portion lOa.
The arm activating assembly further comprises a drive
shaft 51, which is axially disposed through the inside
of the cap body 11 and concentric to the filling cap
axis, having an end 51a mounted on the supporting base
18 and an opposite end 51b engaged, by means of key
52, to an activating element 53, which receives on a
face external to the filling cap lO a torque tool,
such as a manual crank (not illustrated), by which the
user selectively moves said filling cap when it has
been released from the action of the electromagnetic
clutch.
The electromagnetic clutch further comprises a
coupling means displaceable between an engaging
position in which a turn of the drive shaft causes the
axial displacement of the impelling piston, and a
disengaging position, in which the drive shaft rotates
freely when there is torque application thereon, this
coupling means including a transmitting means having
an endless means in the form of an endless screw
tubular element 54, and a pinion 30, which involves
the drive shaft 51, so as to enable it to present only
rotational movement and whose external threaded
surface permits the axial movement of pinion 30
between a cap closed position defined when said pinion
30 is located near the supporting base 18, and an open
cap position, when said pinion 30 is ad~acent to the
end portion of the cap body 11, opposite to the
supporting base 18. The filling cap 10 of the present
invention is provided in the inner portion of cap body
11 thereof, with at least one first and one second
position sensors S1, S2, arranged axially removed one
from the other in order to sense the presence of
pinion 30 in the closed cap and open cap positions. In
the preferred illustrated construction, these sensors
~ 0~
' CA 02232266 1998-03-17
are electronic senso~~s of _n~ "Hall" type -~-h~ ect
the presence of a corresponding emitter S3 o- =nis
system, provided in an external wall portion ol ~_n-on
30 and adjacent to said sensors.
The coupling means further includes adjacen~ ~c each
end of the drive shaft 51, a respective coil mears 60
which, when energized, causes the magnetic coup ing
between the drive shaft 51 and the endless sc~ew
tubular element 54, to permit the axial disp'a~ement
of pinion 30 through the inside of cap body 11 and
consequently the movement of lock arms 14 betwe-r. ~he
open and closed cap positions.
Each coil means 60 comprises a preferably cylin~-'cal
tubular sleeve 61, which concentrically inTol-.-e2 a
respective end portion of drive shaft 51 and _he
adjacent end of the endless screw element 5', ~nd
which is spaced from said parts and supported on an
appropriate supporting base mounted on the cap -ody
11 .
External to the tubular sleeve 61 there is arranqed a
coil 62, which is energized upon the couplinc o~ the
switch element 40 to the filling cap 10, so as to
originate a magnetic field which induces the cou~ling
and retention of tubular sleeve 61 to said coil 62,
impeding the rotational movement of tubular sle-~e 61
in relation to the drive shaft 51, when the turninc of
the latter is caused by the action of the ma-.ual
crank.
The intensity o~ the coupling force should be at l-ast
sufficient to cause an angular phase displac~m_nt
between the turn of the drive shaft 51 and =he
eventual sliding of the tubular sleeve 61 by th~ coil
62, while the clutch is axially displaced bet.:een =he
open and closed filling cap positions.
The tubular sleeve 61 bears, internally, a he~ al
spring element 63, having one end affiYed ~c sc_d
' - CA 02232266 1998-03-17
:;
g . ;,
.
tubular sleeve 61 and the opposite end affixed to the
drive shaft 51, said spring element 63 having a
sufficient axial length to involve the adjacent end
portions of the drive shaft 51 and endless screw
element 54.
The usage of two assemblies of coil means 60 in the
preferred solution is due to having spring torque in
only one turning direction. The spring does not
"adhere" in the opposite direction.
When coupling the electronic switch 40 to the filling
cap 10, first transmitter T1 of the electronic switch
40 informs the second receptor R2 of the filling cap
that the coupling between said parts has been
accomplished and the first optic receptor R1 of said
electronic switch 40 then receives the information
regarding the characteristics and conditions of the
coupled filling cap 10 by means of the second
transmitter T2 thereof. These features will be
compared with the characteristics and conditions,
which are expected for this cap and which have been
previously informed to a central processing unit
(described later on) provided in the electronic switch
40, before said unit commands the unlocking operation
for opening the filling cap 10. If all information is
in agreement, the electronic switch 40 begins to
unlock the electromagnetic lock mechanism, releasing
the cap 10 so that it may be opened manually.
In order to release cap 10 from the electromagnetic
lock, the primary L1 of transformer 41 in the
electronic switch 40 is energized, producing a
magnetic field which induces a current in a
transformer secondary L2 provided in filling cap 10.
This current energizes coil 62, originating a magnetic
field which retains tubular sleeve 61 against the
surface of said coil, avoiding the rotational movement
~ of ~ai~ -e ~r~n ~ ho-~t-~ti-~n ~r Lhc d~ ~f~
' - CA 02232266 1998-03-17
of said sleeve upon the rotation of the drive shart 51.
While in the locking condition, the torque to the drive
shaft 51 causes the free rotation of the tubular sleeve
61 through the coupling thereof to said drive shaft 51
by the spring element 63.
When the coil 62 retains the tubular sleeve 61, the
turning of the drive shaft 51 causes torsion on spring
element 63 which, as it decreases the diameter of the
coils thereof, conducts the contact and the adhesion of
said spring element 63 to the adjacent ends of the drive
shaft 51 and endless screw 54, permitting the transfer
of rotational movement from said drive shaft 51 to said
screw element.
The rotation of the endless screw 54 is then transmitted
to pinion 30 as a linear movement, in order to allow the
axial displacement thereof and of the impelling pistons
15, in order to open filling cap 10. During the opening
movement of filling cap 10, pinion 30 is induced to make
contact, on the front surface thereof, with the first
end of a lock pin 55 mounted on the inside of cap body
11, the second end being opposite to the first end and
projecting from the cap outer surface, preferably
.-~ parallely to the drive shaft 51 of said cap 10 and being
fitted into a housing in the form of a slot pro~7ided at
a coupling end 40a of the electronic switch 40, in order
to lock said switch to the filling cap 10 during the
opening movement of the latter, until said filling cap
10 is once again closed, avoiding a possible changing of
the reservoir cap.
Lock pin 55 is surrounded by a return spring 56, which
is located in the cap body 11 and which is elastically
deformed between a first compression condition, achieved
when cap 10 is opened, defining a maximum spring
compression situation, and a second compression
condition, achieved when cap 10 is in a closed state,
defining a minimum compression situation.
AMEN~~D SHEET
~ CA 02232266 1998-03-17
', ' 11
The maximum or minimum compression conditions are
reached respectively by pinion 30 getting close to or
moving away from the open cap position.
When the clutch reaches the open cap position,
~ 5 electronic switch 40 commands coil 62 of the opening
coil means to deenergize.
Tubular sleeve 61 is released and the endless screw 54
returns to a free rotation state, avoiding any change in
the open state of pinion 30 and consequently the removal
of the electronic switch 40 from the filling cap 10.
These conditions will remain until the closing operation
of said filling cap 10 has begun. -~
After the seating of filling cap 10 onto the feed nozzle
of the reservoir, the electronic switch 40 is
activated and transmitter T1 and receptor R1 elements
communicate with corresponding receptor R2 and
transmitter T2 elements provided in said filling cap 10,
verifying the open state thereof before commanding the
energization of coil 62 of the cap closing coil means
which, as in the opening operation, causes tubular
sleeve 61 to brake, permitting the transmission of the
rotational movement of drive shaft 51 to the endless
screw 54 and the consequent axial movement of pinion 30
from the open condition to the closed condition of said
filling cap 10.
With this movement, lock pin 55 is once again placed in
an inoperative condition, retracted to the inside of cap
body 11 and releasing the electronic switch 40 from the
coupling with filling cap 10. When the closed cap
position is reached, the second position sensor S2
informs said state to electronic switch 40, which
commands that coil 62 no longer be energized, releasing
tubular sleeve 61 to rotate freely.
The opening and closing conditions are communicated to
the operator by means of an audio and/or visual signal
of a defined duration.
AMEND~D SHEET
CA 02232266 l99X ~3-l7
Electronic switch ~0 automatically commands the opening
and closing of filling cap 10, when the exchange of
information between the two indicates that said filling
cap 10 is in one of the closing or opening limit
~ 5 positions. If filling cap 10 is in a position between
said limit positions, electronic switch 40 will inform
the operator, who will decide, by manually acti~.~ating
button 43, the operation to be commanded by electronic
switch 40. When filling cap 10 is closed, a cap
protecting element 19 is mounted against the engaging
portion 16a of said filling cap 10.
In addition to the information regarding the closure of
filling cap 10, the optic communication between said cap
and the activating electronic switch 40 further informs
the latter about the identification of the filling cap
10, the quantity of fuel o~ the tank on which said cap
has been mounted, the date of the last opening thereof,
etc.
Electronic switch 40 may be previously programmed to
identify a number N of caps per trip of the tanker truck
and to store information obtained from these caps for
transmission to an information center.
The transmission of energy and the exchange of
information between filling cap 10 and the
transportation vehicle, in order to cause the locking
and unlocking of said filling cap 10, uses electronic
circuits, which will be described ahead.
Filling cap lO is provided with an electronic system of
energization including a cap feed circuit 100,
presenting the transformer secondary L2 and a first
outlet lOOa, sending electric current, resulting from
the energization of said secondary L2, to a first
microprocessor circuit 110, provided in filling cap 10,
by means of a first inlet llOa thereof.
The first microprocessor circuit llO further presents a
second and a third inlet 110~, llOc, communicating
A,~ DC~: ~' L'--E-
CA 02232266 1998-03-17
13
information from the position detecting circuit 120,
which informs the first microprocessor circuit 110 of
the open state of filling cap 10.
The transformer of the electronic switch 40 is
~ 5 preferably a high frequency oscillator of a power
oscillating circuit 200 of said electronic switch 40 and
~ which presents a first inlet 200a communicating said
oscillating circuit 200 with a second microprocessor
circuit 210 provided in said electronic switch 40, which
receives information to command the opening or closing
of filling cap 10, when optic communication between the
latter and said electronic switch 40 identifies said cap
as being correct and whether it is in a closed or open
state.
The first microprocessor circuit 110 presents as well a
fourth inlet llOd to receive information from the first
optic transmitter T1 of the electronic activating switch
40 through the second optic receptor R2 provided in the
filling cap 10 and electrically connected to the feed
circuit 100 thereof and which commands the start up of
the cap opening and closing operations. The second
transmitter T2 of the filling cap 10 communicates to the
first optic receptor Rl of the electronic switch 40 the
identification data from filling cap 10, when electronic
switch 40 engages filling cap 10, and the data referring
to the end of the operations commanded by said
activating switch 40. These data are sent to the second
optic transmitter T2 of filling cap 10 by a first outlet
llOe of the first microprocessor circuit 110 thereof
which further presents second and third outlets llOf,
llOg communicating respectively with inlet 130a of a
protecting activating element 130 of the cap opening
clutch assembly 140 and an inlet 150a of a protecting
activating element 150 of the cap closing clutch
assembly 160.
AMENI~D SHEE~
- CA 02232266 1998-03-17
14
The communication of each protecting activating element
130, 150 to the respective clutch assembly 140, 160 is
made by connecting each corresponding inlet 140a, 160a
of said activating elements with the respective outlets
130b, 150b of said protecting activating elements 130,
150.
The first microprocessor circuit 210 of electronic
switch 40 presents a first inlet 210a receiving signal
from the outlet 220a of a tension regulating circuit
220; a second inlet 210b, receiving information from
filling cap 10, by means of first optic receptor R2 of
electronic switch 40; a third inlet 210c recei~ing
instructions from activating button 43; a first outlet
210d in communication with first inlet 200a of the power
oscillating circuit 200; a second outlet 210e carrying
instructions to first optic transmitter Tl of electronic
switch 40 to be sent to the electronic circuit of the
filling cap 10; a pair of third outlets 210f, activating
the visual device 43 which informs about the opening or
closing conditions of the filling cap and a fourth
outlet 210g for activating the sound alarm device 43.
The electronic switch 40 also includes a timer which
-~ automatically interrupts the supply of energy to the
oscillator if the operations to be achieved do not occur
within the average time interval, which has been
determined and informed to the second microprocessor 210
circuit of the electronic switch 40, preventing the
system from being inadvertently left on.
AMEN~ED S~FET
