Note: Descriptions are shown in the official language in which they were submitted.
CA 02345410 2007-07-23
-1-
TITLE OF THE INVENTION
ANTI-THEFT DEVICE FOR LAP TOP COMPUTER
BACKGROUND OF THE INVENTION
The present invention relates to an anti-theft device for securing a lap top
computer to a support member such as a desk top.
A variety of techniques and apparatus have been developed over the
years to prevent the unauthorized removal of computer equipment. A number of
anti-theft devices have been developed specifically for tower style and desk
top
computers, as depicted in U.S. patent No. 5,085,395 issued February 4, 1992 to
Fater et al, and U.S. patent No. 4,585,202 issued April 29, 1986 to Parsekin.
Such devices are not designed to be used with clam shell style lap top
computers which are most often the targets of computer theft.
Anti-theft devices which use flexible cables to secure either lap top
computers or tower and desk top style computers are also known. However,
such devices offer iimited security as the cables can often be cut relatively
easily.
There is a need for an anti-theft device that can be used to secure a lap
top computer to a work surface or support member, and which provides an
increased level of security over traditional cable devices.
It is also desirable to provide a lap top computer anti-theft device which
allows for the easy authorized removal of a lap top computer and is cost-
CA 02345410 2001-04-27
-2-
effective to manufacture. It is also desirable to provide an anti-theft device
that
can be used to secure a lap top computer in both the open and closed
positions.
SUMMARY OF THE INVENTION
Accordingly, the present invention provides an anti-theft device for
securing a lap top computer to a support member, the lap top computer having a
first portion and a second portion pivotally connected together for movement
between an open position in which the first portion extends at an angle from
the
second portion, and a closed position in which the first portion and second
portion are substantially parallel to and adjacent to each other. The device
includes a rigid securing member having back, side and front restraining
members defining an elongate opening dimensioned to slidably receive the first
portion therethrough. The device further includes a locking assembly having a
first part rigidly coupled to the securing member and a second part adapted to
be anchored to the support member, the first and second parts being movable
together into a securing position, and apart into a release position. When a
lap
top computer is positioned on the support member in an open position with the
first portion extending through the elongate opening and the locking assembly
is
moved to the securing position, the second portion is confined between .the
securing member and the support member and the first portion is confined
within
the elongate opening to prevent removal of the lap top from the support
member. When the locking assembly is moved to the release position, the
securing member is moved away from the support member a distance which
allows the lap top computer to be removed from the support member.
CA 02345410 2001-04-27 -
-3-
The anti-theft device may include a further rigid securing member
adapted to interlock with and be positioned generally transversely to said
rigid
securing member to secure a lap top in the closed position to a support
member.
BRIEF DESCRIPTION OF THE DRAWINGS
For a better understanding of the invention, and to show how it may be
carried into effect, reference will now be made, by way of example, to the
accompanying drawings, in which:
Figure 1 is an isometric view of an anti-theft device in accordance with a
first preferred embodiment of the invention;
Figure 2 is an isometric view of the anti-theft device of Figure 1 shown in
use securing a lap top computer in the open position to a desk top;
Figure 3 is a front view of the anti-theft device of Figure 1 shown in use
securing the open lap top computer to the desk top;
Figure 4 is an isometric view showing the anti-theft device of Figure 1 in
use securing the lap'top computer in the closed position to the desk top;
Figure 5 is an enlarged partial cross-sectional view taken generally along
line V-V of Figure 1 showing a locking assembly of the device being actuated
to
bring the locking assembly into a securing position;
Figure 6 is a view similar to the view of Figure 5, showing the locking
assembly being moved to a release position;
Figure 7 is an enlarged cross-sectional view of the locking assembly
taken along line VII VII of Figure 3;
Figure 8 is an isometric view of a second preferred embodiment of an
CA 02345410 2001-04-27
-4-
anti-theft device in accordance with the present invention;
Figure 9 is an isometric exploded view of an anti-theft device according to
a third preferred embodiment of the invention for use in securing an open lap
top to a desk top; and
Figure 10 is a view similar to the view of Figure 9 showing an alternative
method of securing a locking leg of the anti-theft device of Figure 9 to the
desk
top.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to Figures 1 and 2, an anti-theft device, indicated generally by
reference numeral number 10, for securing a lap top computer 12 to a support
member such as a desk top 14, is shown. The lap top 12 has a first portion in
the form of a monitor portion 16 and a second portion in the form of a
keyboard
portion 18 pivotally connected to the monitor portion 16 for movement about a
hinge 19 between an open position (shown in Figures 2 and 3) in which the
monitor portion 16 extends at an angle from the keyboard portion 18, and a
closed position (shown in Figure 4) in which the monitor portion 16 and
keyboard portion 18 are substantially parallel to and adjacent to each other.
The device 10 includes a rigid securing member designated generally by
reference numeral 20 made of hardened tubular steel provided with a vinyl
coating. The securing member 20 has an elongate back restraining member 22
and a pair of U-shaped side restraining members 24, 26 extending from
respective opposite ends of the back restraining member 22. The securing
member 20 also has a pair of front restraining members 28, 30 extending
CA 02345410 2001-04-27
-5-
inwardly from the front ends of the respective side restraining members 24,26
in
generally parallel relationship to the back restraining member 22. The
securing
member 20 is dimensioned to define an elongate opening 32 (Figure 1) which
can slidably receive the monitor portion 16 therethrough.
The device 10 also includes a locking assembly indicated generally by
numeral 34 in Figure 1 having a first part in the form of a first leg 36 made
of a
hardened tubular steel rod rigidly attached to and extending downwardly from
the side restraining member 24 of the securing member 20. The locking
assembly also has a second part in the form of a locking device 38 which is
telescopically engageable with and securable to the first leg 36 at a selected
one of a plurality of locations along the length of the leg 36, as will be
described
in more detail below.
In this embodiment, the anti-theft device 10 also has a second leg 40
rigidly attached to and extending downwardly from the other side restraining
member 26. The second leg 40 has a smooth outer exterior, and extends
parallel to and is spaced from the first leg 36 a distance such that the legs
36,
40 can straddle the width of the lap top computer 12. As can best be seen with
reference to Figure 3, to use the device 10, the lap top 12 is placed on an
upper
surface 42 of the desk top 14 between a pair of spaced apart predetermined
holes 44, 46 extending through the desk top 14 from the upper surface 42
through to a lower surface 48 thereof. The holes 44, 46 are reinforced by
plastic tubular plugs 50, 52 which have been inserted into the holes 44, 46
and
which also facilitate the insertion and removal of the device 10 in and from
the
holes 44, 46. The securing member 20 is then slid over the monitor portion 16
CA 02345410 2001-04-27
-6-
so that the monitor portion 16 is received within the elongate opening 32. At
the
same time, the first and second legs 36, 40 are inserted in the tubular plugs
50,
52, respectively, and moved downwardly to extend partly below the desk top 14
until the securing member 20 engages the top of the keyboard portion 18. The
first leg 36 and the locking device 38 are moveable together into a securing
position by telescoping the locking device 38 upwardly and locking it to the
first
leg 36 below the desk top 14 to clamp the keyboard portion 18 and desk top 14
together between the securing member 20 and locking device 38. When so
clamped, the monitor portion 16 is confined within the elongate opening 32.
Thus, forward and upward motion of the lap top 12 are restricted by the front
restraining members 28, 30. The back restraining member 22 restrains
rearward motion. Sideways motion is similarly restricted by the side
restraining
members 24, 26. Removal of the lap top 12 is thus prevented. Clearly, for the
device 10 to work, the tocking.device 38 must be dimensioned to be larger than
the hole 44 with the tubular plug 50 mounted therein so that an attempt to
remove the securing member 20 from the desktop14 would be prevented by the
locking device 38 engaging the lower surface 48 of the desk top 14, thereby
restricting further upward motion of the securing member 20. It will be
appreciated that when the locking device 38 is secured to the first leg 36,
the
locking device 38 is effectively anchored to the desk top 14, thereby
anchoring
other portions of the device 10 to which the locking device 38 is secured.
When it is desired to remove or transport the lap top 12, the locking
device 38 is disengaged from the first leg 36 and the securing member 20 is
moved to a release position by lifting it upwardly and away from the desk top
14
CA 02345410 2001-04-27
-7-
a distance which would allow the lap top computer 12 to be removed. Of
course, the securing member 20 may be removed completely and set aside
when not in use.
The locking assembly 34 will now be described in detail with reference to
Figures 5 to 7. As seen in Figures 5 and 6, the first leg 36 includes a
plurality
of ratchet teeth 54 spaced along the length thereof. The locking device 38 has
a hardened steel lock housing 55 having a blind hole 57 in which is situated a
spring-loaded pawl 56. The spring-loaded pawl 56 is normally biased into a
locked position (shown in Figures 5 and 7) under the influence of a spring 58.
In this position, the spring 58 biases the pawl 56 part way into a passageway
60
of the locking device 38 for receiving the first leg 36 therethrough. The pawl
56
presents an inclined surface 62 (labelled only in Figure 5) for meeting a
frusto-
conical surface 63 of the ratchet teeth 54. Such allows the first leg 36 to be
advanced within the passageway 60 relative to the locking device 38 in the
direction of arrow 64 shown in Figure 5. When moved in this direction the pawl
56 is pushed into the blind hole 57, by each ratchet tooth 54 passing the pawl
56. As each ratchet tooth 54 passes the pawl 56, the spring 58 urges the pawl
56 back into an annular space 67 between adjacent ratchet teeth 54. When the
pawl 56 is positioned in the annular space 67, movement of the first leg 36 in
a
direction opposite to the direction shown by arrow 64, relative to the locking
device 38, is blocked by the engagement of a transversely-extending planar
lower surface 68 of the pawl 56 with a portion of a planar annular surface 70
of
a subject ratchet tooth 54 (as shown in Figure 6). Thus, the spring-loaded
pawl
56 permits the locking device 38 to be telescoped onto the first leg 36 while
CA 02345410 2001-04-27
-8-
preventing the locking device 38 from being removed therefrom when the
locking device 38 is in the locked position.
To unlock the device 38, a key 72 (shown in Figures 1 and 3) is inserted
into a key hole in a.key lock cylinder 74 which is seated and retained in a
key
lock cylinder hole 75 by a locking pin 88. The key lock cylinder hole 75
extends
at a right angle to the blind hole 57. The key lock cylinder 74 has a torque
blade 76 which extends into a groove 78 formed in the pawl 56 to bear against
a
torque blade surface 80 of the pawl 56. Rotating the key 72 clockwise, causes
the torque blade 76 to rotate and displace pawl 56 into the blind hole 57, to
compress the spring 58, and away from the passageway 60 (as shown in Figure
6). In this position, the locking device 38 is unlocked and the first leg 36
may be
removed from the steel lock housing 55 as shown by arrows 84, 86 in Figure 6.
Releasing the key 72 causes the pawl 56 to enter the passageway 60 under the
influence of the spring 58.
Referring now to Figures 1 and 4, it will be seen that the device 10 has a
second rigid securing member 90 for use in securing the lap top computer 12 in
a closed position. The second securing member 90 includes an elongate
intermediate member or bar 92 with first and second stop members 94, 96
located at opposite ends thereof. In the embodiment shown, the first and
second
stop members 94, 96 are each downwardly arcuate bars. The second securing
member 90 and first securing member 20 are each configured such that they
interlock with each other. In particular, in the illustrated embodiment, the
back
restraining member 22 has a raised central portion 98 under which the
intermediate bar 92 can pass. An arcuate member 100 is provided on the upper
CA 02345410 2001-04-27
-9-
side of the intermediate bar 92 and together they define an opening 102
through which the back restraining member 22 passes.
With reference to Figure 4, the closed lap top 12 is positioned between
the holes 44, 46 such that it can be straddled by the first and second legs 36
and 40 when the legs are inserted through the holes 44, 46. Prior to mounting
the first securing member 20 to the desk top 14, the first and second securing
members 20 and 90 are interlocked by threading one of the legs 36, 40 through
the opening 102 of the second securing member 90 until the intermediate bar 92
is located under the raised central portion 98 of the back restraining member
22.
The first and second securing members 20, 90 are then secured to the desk top
14 over the lap top computer 12 as illustrated by inserting the first and
second
legs 36, 40 through the holes 44, 46 in the desk top 14 until the securing
members 20, 90 contact an upper surface of the lap top computer 12. The
locking device 38 is then secured to the first leg 36 as discussed above.
The raised central portion 98 of the back restraining member 22 provides
clearance for the intermediate bar 92 to pass underneath the back restraining
member 22. The first and second arcuate stop members 94 and.96 each '_ ;._ .
preferably include a pair of feet 104, 106 which rest on the desk top.14.
Once the first and second securing members 20, 90 are secured to the--
desk top 14 over the closed lap top computer 12, the first and second legs 36;
;.
40 restrain sideways movement of the computer 12, and the first and second -
stop members 94, 96 restrain forward and backward movement. Upward
movement is restrained by the intermediate bar 92, and the back and front
restraining members 22, 28 and 30.
CA 02345410 2001-04-27
-10-
The sizing of the first and second securing members 20 and 90 is
preferably such that the anti-theft device 10 can be used with different lap
top
computers falling within a predetermined range of conventional sizes.
With reference to Figure 8, a further possible embodiment of an anti-theft
device, indicated generally by reference numeral 110, is illustrated. The anti-
theft device 110, which is suitable for securing a lap top computer in the
open
position only, is identical in construction and operation to the anti-theft
device
described above, and similar reference numerals have been used to denote
similar parts. The device 110 differs from the device 10 only in that the
device
10 110 includes a single leg 36 for insertion through the desk top 14 and does
not
include a second securing member 90.
Figures 9 and 10 illustrate an anti-theft device 210 according to a third
preferred embodiment of the invention. This embodiment 210 is to be preferred
in situations where access to a locking assembly 234 above the desk top 14 is
desired. Similar to the anti-theft device 110 described above, the anti-theft
device 210 is for securing a lap top -computer 12 in the open position and
includes a rigid securing member 220 made of hardened tubular steel provided
with a vinyl coating. The securing member'220 has an elongate back
restraining member 222 and a pair of U-shaped side restraining members 224,
226 extending from respective opposite ends of the back restraining member
222. The securing member 220 alsQ has a pair of front restraining members
228, 230 extending inwardly from the front ends of the respective side
restraining members 224, 226 in generally parallel relationship to the back
restraining member 222. The securing member 220 is dimensioned to define an
CA 02345410 2001-04-27
-11-
elongate opening 232 which can slideably receive the monitor portion 16 of the
lap top 12 therethrough.
The device 210 also includes a locking assembly 234 having first and
second parts. The second part is in the form of a leg 236 made of a hardened
tubular steel rod rigidly attached to and extending upwardly from an anchor
member in the form of a circular base plate 239 provided with a plurality of
holes
241 for use in securing the base plate and hence leg 236 to the desk top 14
using bolts, washers and nuts 243, 245, 247. The first part is in the form of
a
locking device 238 rigidly attached to the side restraining member 224. The
locking device 238 is similar in construction and operation to the locking
device
38 and will thus not be described further except to point out that the locking
device 238 is configured to receive the leg 236 from below rather than from
above, as in the case of the locking device 38. Suitable modifications to the
locking device 238 to ensure its operation in this manner will become apparent
to the person skilled in the art. Thus, the locking device 238 is
telescopically
engageable with and securable to the leg 236 at a selected one of a plurality
of
locations along the length of the leg 236 in a similar manner as described
above
with respect to the first and second preferred embodiments.
The anti-theft device 210 can be used in one of two ways. Referring to
Figure 9, the first way is to bolt the base plate 239 to the upper surface 42
of the
desk top 14 with the leg 236 extending upwardly in a normal direction from the
base plate 239. The lap top 12 can then be positioned adjacent to the leg 236
in the open position and the securing member 220 slid down over the monitor
portion 16 with the monitor portion 16 received within the elongate opening
232.
CA 02345410 2001-04-27
-12-
At the same time, the locking device 238 is telescoped downwardly and locked
to the leg 236 to clamp the keyboard portion 18 to the desk top 14. When so
clamped, the monitor portion 16 is confined within the elongate opening 232.
Thus, forward and upward motion of the lap top 12 are restricted by the front
restraining members 238, 230. The back restraining member 222 restrains
rearward motion. Sideways motion is similarly restricted by the side
restraining
members 224, 226. Removal of the lap top 12 is thus prevented.
Referring to Figure 10, the anti-theft device 210 may be used in a second
way to secure the lap top 12 to a desk top 14 having a predetermined hole 44
extending between upper and lower surfaces thereof. The leg 236 may be
inserted through the hole 44 from below the desk top 14 so as to extend partly
above the desk top 14, and held in position using bolts 249 which affix the
circular base plate 239 to a lower surface of the desk top 14. The locking
device 238 may then be telescoped onto and locked to the leg 236 from above
the desk top 14, thereby clamping the keyboard portion 18 and desk top 14
between the securing member 220 and the base plate 239. As in the case of
the first and second preferred embodiments, a hollow tubular plastic plug 250
is
seated in the hole 44 to facilitate insertion and removal of the leg 236 as
well as
to reinforce the hole 44 against damage. In this case, however, the plug 250
has a widened annular flange 252 apertured to permit the flange 252 to be
secured to the upper surface 42 of the desk top 14 using screws 254.
It will be appreciated that the front restraining members 28, 30 or 228,
230 in the illustrated embodiments could be replaced with a single piece
extending between the two side restraining members 24, 26 or 224, 226.
CA 02345410 2001-04-27
-13-
However, the use of two separate front restraining members offers a benefit in
that it minimizes visual interference with the monitor portion 16. It will
also be
appreciated that the anti-theft devices 10, 110 and 210 need not include front
restraining members at all if they are only used to secure the lap top
computer
in the closed position.
It will be appreciated that a different locking means could be used to
secure the first leg 36, 236 other than that described above. For example, a
series of spaced holes could be provided along the length of first leg 36, 236
and used in conjunction with a padlock to secure the lap top computer to the
desktop.
As will be apparent to those skilled in the art in the light of the foregoing
disclosure, many alterations and modifications are possible in the practice of
this invention without departing from the spirit or scope thereof. The
foregoing
description is of the preferred embodiments and is by way of example only, and
is not to limit the scope of the invention.