[0001] This invention relates to a mounting arrangement for a lid or door lock and particularly
but not exclusively to a mounting arrangement for the lock of a luggage compartment
door or tailgate of a motor vehicle.
[0002] Accordingly the present invention will be described below with reference to motor
vehicles but it should be appreciated that the invention may be employed for a lock
on any lid or door which lock may be susceptible to being forcibly removed particularly
by pulling it out to gain access to an opening mechanism.
[0003] While the protection against theft of personal valuables carried in a motor vehicle
may often be improved by locking such items in the luggage or rear compartment of
the vehicle, such compartments are vulnerable to being broken into.
[0004] Common methods employed for breaking into such compartments include forcible removal
of the cylinder of the lock to gain access to the door release mechanism. This may
be done by applying high torque to the lock cylinder to wrench it out of its supporting
surfaces (sometimes referred to as "torquing out"). Alternatively, high pulling forces
may be applied to pull out the cylinder (sometimes referred to generally as "pulling
out"). Further, by applying high leverage forces to the cylinder the supporting surfaces
may be bent or distorted to permit cylinder removal or to otherwise gain access to
the release mechanism (sometimes referred to generally as "bending out").
[0005] While it has been proposed, for example, in US Patent Specification 4 041 741, to
apply a protective plate to the outside of the door to prevent the lock from being
pulled out, this is an aesthetically unattractive solution proposal. Further, the
proposal of this US Patent 4 041 741 requires additional holes to be produced through
the door skin, which adds to potential corrosion sites.
[0006] It is also known from US Patent Specification 3 868 836 to provide a bracket within
the door to support an inner end of a lock barrel. In this construction, a limited
resistance to twisting of the lock mechanism in the panel is achieved by engagement
of flats on the barrel with opposite legs of a spring clip.
[0007] According to the present invention, there is provided a mounting arrangement for
mounting a lock to a vehicle skin panel, the arrangement comprising a lock cylinder,
a hole in the skin panel for receiving the lock cylinder, a bracket which has a foot
portion fixed to the skin panel at a distance from the inner surface of the skin panel,
and an upstanding portion, characterised in that the arrangement includes a plate
mounted on the cylinder and fixed against rotation relative to the cylinder, the plate
locating behind the bracket so that engagement of the plate against the bracket resists
pull-out forces exerted on the cylinder, and wherein the upstanding portion is provided
with spaced holes and the plate has corresponding spigots which fit in the holes to
resist twisting forces exerted on the cylinder.
[0008] While the bracket, plate and lock barrel are preferably made of metal, other materials
having satisfactory strength may alternatively or additionally be employed.
[0009] In this latter context it is important that the bracket can be firmly welded or otherwise
fixed to the material of the skin of the enclosure. Accordingly, when the enclosure
comprises a compartment of a motor vehicle and having a skin of metal, a metal bracket
may be easily welded to the inner surface of the skin, by spot-welding for example,
during the process of vehicle manufacture. To this extent, subsequent finishing processes
applied to the skin may be applied also to the bracket. The bracket is shaped to permit
it to be bonded to the inner surface of the skin while presenting an upstanding portion
spaced from the inner skin and on which the plate of the mounting is directly or indirectly
locatable. Preferably, the bracket has a substantially planar foot portion that is
bonded to the skin and an upstanding substantially planar portion at right angles
thereto.
[0010] It is preferred that the plate has a non-circular hole, and the cylinder has a corresponding
non-circular part which fits through the hole so that the plate cannot rotate relative
to the cylinder. The arrangement preferably also includes a retaining clip adapted
to fit into a groove on the end of the cylinder to retain the plate on the cylinder.
[0011] The retaining clip can occupies the groove around at least 120° of arc, preferably
substantially 180° of arc.
[0012] The cylinder can have a radially extending flange at its key-receiving end, and a
tubular spacer sleeve can be fitted around the cylinder to space the plate from the
flange.
[0013] The plate is provided with locating spigots to closely locate into the holes in the
bracket with the plate in position and attached to the cylinder to thereby locate
the plate on the bracket. It will be seen that in such an arrangement, if a high torque
is applied to the cylinder and plate this will be resisted by the spigots.
[0014] It will be appreciated that the thickness and strength of the plate and bracket can
readily be tailored to levels necessary to prevent or at least impair pulling out
of the cylinder and, as may be desired, torquing out and bending out also. Bending
out is clearly resisted by the support given to the cylinder, at a distance spaced
from the skin panel by the plate and bracket for example via located spigots and through
any direct contact made between the cylinder and the upper edge of the bracket.
[0015] In a preferred embodiment the spacing of at least two of the spigots is preferably
such that lines drawn from the centre lines of the spigots to the longitudinal axis
of the cylinder and perpendicular thereto form an obtuse angle between one another.
[0016] It will be appreciated that in mounting the lock to for example, a motor vehicle
luggage compartment door or tailgate, the end flange on the cylinder may be backed
by a resilient seal. Such a seal enables the atmospheric elements to be excluded from
around the bezel or flange, provides protection for surrounding paintwork and some
resilience to allow for functional tolerances.
[0017] The spigots which may be provided on the plate are preferably of the same material
type as the plate and are preferably studs welded on or through the plate but alternatively
they may be for example threaded studs or bolts screwed through the plate.
[0018] The present invention will now be further described by way of example, with reference
to the accompanying drawings in which:
Figure 1 is a schematic view of the rear end of a motor vehicle indicating the position
of a lock mounting arrangement in accordance with the invention;
Figure 2 is a forward looking elevation of a mounting arrangement according to the
invention;
Figure 3 illustrates in side elevation and in part section the mounting shown in Figure
1 assembled with a lock cylinder inserted through a vehicle door skin;
Figure 4 illustrates in part section the manner of attachment of the plate to the
cylinder shown in Figure 2;
Figure 5 is a perspective view of part of the mounting; and
Figure 6 is an exploded view of a cylinder and spring clip.
[0019] In Figure 1, the position of a lock mounting arrangement according to this invention
is indicated by the dotted outline signified by X.
[0020] Figures 2 to 5 show a bracket 1 provided with strengthening ribs 2 which is spot
welded along the length of its substantially planar foot portion 3 to the inside of
a vehicle door skin 4. An upstanding substantially planar portion 5 of the bracket
1 is at right angles to the foot portion 3. The upstanding portion is provided with
two spaced holes 6 and 7.
[0021] The upstanding portion 5 is further provided with a recess 19 in its upper edge.
A lock cylinder 9 has a flange 17 at its key-receiving end. The cylinder is inserted
through an opening in the door skin 4 and is accommodated in the recess 19.
[0022] A plate 8 is attached to the lock cylinder 9 by a spring clip 10 which enters a peripheral
groove 20 situated near the cylinder end (shown in Figure 4 which is in part section
for this purpose and also shown in Figure 6). the groove 20 extends completely around
the cylinder 9, and the clip 10 occupies about 180° of arc when fitted in the groove
20. The plate is positioned relative to the flange 17 and to the skin panel 4 with
the aid of a tubular spacer sleeve 11. The plate 8 is illustrated having an extension
12 and a side plate 13 which serve to brace the plate 8 and also provide a convenient
housing for an electrical switch (not shown). The plate 8 is provided with two spigots
14 and 15 welded to the plate 8. The spigots are of such length and diameter as to
fit and extend through the holes 6 and 7 to thereby locate the plate 8 on the bracket
1.
[0023] The plate 8 is provided with a hole 16 having a shaped, non-circular edge in conformation
with the external non-circular shape of the lock cylinder 9. A similar hole is provided
through the vehicle door skin 4. A flange 17 is provided on the outward end of the
lock cylinder and a rubber seal 18 is shown in Figure 3 inserted between the flange
and the door skin.
[0024] In mounting the lock cylinder 9 within the door skin 4; with the bracket 1 welded
to the skin 4, the end of the lock cylinder is passed through the hole provided in
the skin 4 until the seal 18 provided under the flange 17 contacts the skin 4. The
tubular spacer sleeve 11 of suitable length is placed over the cylinder and the end
of the cylinder remote from the flange 17 is passed through the shaped hole in the
plate 8. The plate is pushed onto the cylinder until it contacts the end of the spacer
11 and the spigots 14 and 15 become aligned with and enter the holes 6 and 7 in the
bracket 1 to thereby establish location of the plate 8 on the bracket 1. With light
pressure being applied in opposing directions to the bezel end of the cylinder and
to the plate 8, the spring clip 10 is inserted in the groove 20 to thus attach the
plate 8 to the cylinder 9. The spring tangs 21 of the clip 10 press against an inner
surface of the groove 20 to retain the clip 10 in position and the fingers 22 of the
clip 10 extend beyond the groove 20 and the lateral edges of the hole in the plate
8 to prevent the cylinder 9 from being removed from the plate 8.
[0025] It will be seen that rotation of the cylinder 9 relative to the door skin 4 will
be resisted not only by the non-circular shape of the hole in the door skin 4 but
more importantly by the shape of the hole in the plate 8 which is itself supported
against rotation by the spigots 14 and 15 engaging in the holes 6 and 7. Thus, torquing
out of the cylinder will be strongly resisted. Bending out of the cylinder will clearly
be strongly resisted by the arrangement, support coming from the bracket 1 through
the spigots 14 and 15 to the plate 8; direct support from the bracket 1 is also available
in the event of direct contact between the cylinder 9 and the recess 19 at the edge
of the upstanding portion 5 of the bracket 1.
[0026] The mounting illustrated will also resist pulling out of the cylinder of the lock
because the plate 8 is locked to the cylinder by the clip 10, and axial movement of
the plate is blocked by the bracket 1.
1. A mounting arrangement for mounting a lock to a vehicle skin panel, the arrangement
comprising a lock cylinder (9), a hole in the skin panel (4) for receiving the lock
cylinder, a bracket (1) which has a foot portion (3) fixed to the skin panel (4) at
a distance from the inner surface of the skin panel, and an upstanding portion (5),
characterised in that the arrangement includes a plate (8) mounted on the cylinder
(9) and fixed against rotation relative to the cylinder, the plate locating behind
the bracket (1) so that engagement of the plate against the bracket resists pull-out
forces exerted on the cylinder, and wherein the upstanding portion (5) is provided
with spaced holes (6,7) and the plate (8) has corresponding spigots (14,15) which
fit in the holes to resist twisting forces exerted on the cylinder (9).
2. An arrangement as claimed in Claim 1, characterised in that the plate (8) has a non-circular
hole (16), and the cylinder (9) has a corresponding non-circular part which fits through
the hole so that the plate cannot rotate relative to the cylinder, the arrangement
also including a retaining clip (10) adapted to fit into a groove (20) on the end
of the cylinder to retain the plate on the cylinder.
3. An arrangement as claimed in Claim 2, characterised in that the retaining clip occupies
the groove around at least 120° of arc.
4. An arrangement as claimed in any preceding claim, characterised in that the cylinder
(9) has a radially extending flange (17) at its key-receiving end, and a tubular spacer
sleeve (11) is fitted around the cylinder to space the plate (8) from the flange.
5. A luggage compartment lid including a mounting arrangement as claimed in any preceding
claim.