U.S. patent number 3,913,962 [Application Number 04/664,764] was granted by the patent office on 1975-10-21 for portable door lock.
Invention is credited to Kenneth H. Briggs.
United States Patent |
3,913,962 |
Briggs |
October 21, 1975 |
Portable door lock
Abstract
A plate having projecting tabs for engaging a latch recess in a
door frame and a bolt which slidably engages an angled slot in the
plate which permits the bolt to be wedged against the door.
Inventors: |
Briggs; Kenneth H. (Berkeley,
CA) |
Family
ID: |
24667348 |
Appl.
No.: |
04/664,764 |
Filed: |
August 31, 1967 |
Current U.S.
Class: |
292/292 |
Current CPC
Class: |
E05C
19/182 (20130101); Y10T 292/379 (20150401) |
Current International
Class: |
E05C
19/00 (20060101); E05C 19/18 (20060101); E05C
019/18 () |
Field of
Search: |
;292/288,289,290,292,295,296,297,298,265,266,267,268,269,270,271,272,273,274 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Moore; Richard E.
Attorney, Agent or Firm: Bruce & McCoy
Claims
I claim:
1. A portable door lock for use in a door assembly having a door
hinged at one vertical edge for unidirectional opening, a door jamb
adjacent the other vertical edge, and a latch recess in said jamb,
the securer comprising
a relatively thin metal base plate for fitting between the edge of
the door and the adjacent jamb when the door is closed, said plate
having first and second ends,
a tongue projecting at approximately right angles from each end of
said plate in spaced relation thereto for fitting in and engaging
the side of the latch recess in said jamb,
a pair of elongated slots having serrated edges formed in said base
plate, said slots angled with respect to each other and forming an
inverted "V" and having an enlarged opening at their common
ends,
a bolt having an annular groove around one end thereof for mating
with the serrated edges of either of said slots in positively
engaged and selective sliding relation for adjustment therealong
and wedging against said door when it is closed, and
the ends of said plates adjacent said tongues forming stabilizing
projections on both sides of said tongues, said projections spaced
to permit a spring latch deadlock to fit therebetween.
2. A portable door lock comprising
a relatively thin plate for fitting between the edge of a door and
its jamb,
at least one tongue extending relatively perpendicular from said
plate proximate one end thereof, but spaced therefrom, for engaging
a latch recess in the door jamb,
an elongated serrated edged slot having an enlarged opening and
formed at an angle with respect to said tongue, and
a bolt formed with an annular groove around one end thereof for
mating with the edges of said slot in positively engaged and
selective sliding relation for adjustment therealong into wedged
abutting relation with the face of the door.
3. A portable door lock comprising
a relatively thin plate for fitting between the edge of a door and
its jamb,
at least one tongue extending relatively perpendicular from said
plate proximate one end thereof, but spaced therefrom, for engaging
a latch recess in the door jamb,
an elongated serrated edged slot formed at an angle with respect to
said tongue, and
a bolt formed for positively engaged sliding relation in said slot
for adjustment therealong into wedged abutting relation with the
face of the door, said bolt being secured to said base plate by a
flexible connecting means.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to door locks and more particularly
to a portable safety door lock which can be used to secure a door
from the inside without the use of tools or keys.
2. Description of the Prior Art
There are many occasions when it is desirable to have a portable
lock which can be used on interior doors of a building or house
where they are not provided, or on doors which have defective or
broken locks. It is also often desirable to double lock doors which
are operable by a skeleton key or a jimmying material, such as a
thin piece of celluloid. In order to avoid the expense and time
required to install locks on these doors, a portable door lock is
required which is of a simple construction and can be installed and
removed without marring the paint or injuring the surface of the
door or surrounding woodwork.
Where it is desirable to secure a door temporarily for short
periods of time, such as during a stay at a motel, hotel, or other
public accommodations, the inconvenience of installing a lock on
such a door usually prevents such additional locks from being used.
As a result of these circumstances, a portable lock is required
which can be easily and quickly installed and released and which
permits reasonably unimpeded use of the door.
Many travelers and people living in apartments, dormitories, and
rooming houses prefer to utilize a safety lock for additional
protection of their personal property and safety. Such a lock must
be small, lightweight, inexpensive, simple to install and release,
and most of all it must be an effective lock. In order to meet
these requirements, many different types of devices have been made,
but in general most of these devices have one or more
characteristics which make them unsuitable for universal
application in all of the situations here considered. They
generally have too many parts for simple assembly, or they dig into
or injure the woodwork, or they are not adaptable to doors with
different thicknesses, or most importantly they are simply
ineffective as a door lock.
It is therefore an important object of the present invention to
provide a portable door lock which is universally adaptable to
various types and thicknesses of doors.
It is another object of the present invention to provide a door
securer which effectively locks a door without injuring the
woodwork of the door or the door jamb.
It is a further object of the present invention to provide a
portable door lock which utilizes only two coacting parts.
It is still another object of the present invention to provide a
portable door lock which can be readily installed and removed.
And yet a further object of the present invention is to provide a
portable door lock which is lightweight, small, and relatively
inexpensive to manufacture.
SUMMARY OF THE INVENTION
The present invention meets all of the requirements heretofore
stated. It comprises a relatively thin plate for fitting between
the edge of a door and its jamb. The plate has a projecting means
for engaging a latch recess in the jamb. A track means on the plate
is inclined with respect to the plane of the door when the plate is
disposed in operating position between the door and its jamb. A
bolt means is provided which is selectively engagable with the
track means and extends across at least a portion of the face of
the door when the door is closed and when the bolt means is
engaging the track means and when the projecting means is engaging
the latch recess in the door jamb. When the bolt means is moved
along the track toward the door, it will abut and restrain the door
in its closed position.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the portable door lock of the
present invention;
FIG. 2 is a bottom plan view of the present invention;
FIG. 3 is a top plan view of the present invention;
FIG. 4 is an end view of the present invention;
FIG. 5 is a cross section of a closed door and door jamb showing
the present invention in operating position; and
FIG. 6 is a side elevation of the bolt of the present
invention.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Reference is made to the drawings for the details of a specific
embodiment of the present invention. There shown is a stamped base
plate 11 for fitting between the end of a door 13 and its jamb 15.
It is made of a relatively thin but strong material, such as nickel
plated steel, in order to withstand bending stresses when a force
is applied to the door to force it open.
The two edges of the plate have been stamped into an offset
configuration 17 to provide additional strength to the plate along
those edges.
In the preferred embodiment, the base plate is constructed
symmetrical about a center line A--A, in order to accommodate doors
hinged from either vertical edge or doors opening in either
direction. Each half of the plate around centerline A--A is a
mirror image of the other half.
The device shown has a projecting means 19 for engaging a latch
recess 21 of the jamb. In the present invention, the projecting
means comprises a tongue 19 which projects or extends relatively
perpendicular from the plate proximate one end thereof, but spaced
therefrom. In other words, the tongue is disposed in spaced
relation to the end of the plate. This tongue engages the latch
well or latch recess of the typical striker plate 23 which is
secured to the face of a door jamb. The tongue can be split into
parallel projections to accommodate a deadlock bolt.
The tongue is disposed at a position removed from the end of the
plate in order to provide the stabilizing projections 25 which
surround or extend across the latch well in abutting relation to
the striker plate. The stabilizing projections effect a secure
positioning of the base plate against the striker plate and
engaging of the tongue in the latch well. The stabilizing
projections are spaced laterally from the tongue to keep them
seated on the striker plate of the door jamb rather than projecting
across the latch recess. The stabilizers could be formed with a
cross bar at their ends for further rigidity.
A track means 27 is formed on the plate and is inclined with
respect to the plane of the door when the plate is disposed in
operating position between the door and its jamb. In the present
invention, the track means comprises a "V" shaped slot having
serrated edges 29. Each leg of the slot is inclined at an angle
with respect to the plane of the tongues which parallel the plane
of the door. The slot has an enlarged opening 31 at the common ends
of the two legs thereof. As an alternative, the track could be
milled out of the base plate or otherwise formed thereon without
departing from the contemplated invention. Likewise, the slot could
comprise individual channels, each having enlarged portions at one
of their ends.
A bolt means 33 is provided which is selectively engagable with the
track means of the plate. The bolt means extends across at least a
portion of the face of the door when the door is closed and when
the bolt means is engaging the track means and the projecting means
is engaging a latch recess in the door jamb. When the bolt means is
moved along the track toward the door, it comes into contact with
and abuts the door whereby it restrains the door in its closed
position.
The bolt means is formed with an annular groove 35 which engages
the serrated edges of the slot for selective positive engagement
therealong. Selective positive engagement means that the bolt means
can be moved to any position along the track, which is defined as a
selective position, and it will remain in that position as a result
of the serrated edges and will not move back along the track. This
latter feature provides the definition of positive engagement
therealong.
The bolt means 33 is secured to the base plate 11 by a flexible
connecting means 37, such as a small length of metal chain. The
chain passes through a hole 39 in the bolt and a stamped loop 41 on
the base plate. The connecting means prevents the plate and bolt
from becoming separated or one of them from being lost.
The slotted plate and bolt can be engaged to coact by inserting the
annular grooved end of the bolt through the enlarged hole of the
slot and aligning the annular groove with the serrated edges and
then sliding the bolt along the slot with the serrated edges
engaged within the annular groove on the bolt. The bolt and plate
coact to effect a positive sliding engagement whereby the bolt
cannot be pulled out of the slot except through the enlarged
opening. The bolt can be slid along the slot, which is angled with
respect to the door, and thereby wedged into abutting relation
against the face of the door. The angle and the serrated edges of
the slot prevent an outside opening force on the door from sliding
the bolt and opening the door. If the slot angle is too great,
pressure on the door will slide the bolt along the slot, and if the
angle is too small, the door securer will be severely limited in
its adaptability to various thicknesses of doors unless it is made
wider so the slot can be longer.
The head or end of the bolt which contains the annular groove must
be made thick enough to withstand considerable bending force on the
bolt in order to keep the door locked. Likewise, the thickness of
the width of the annular groove must be only slightly greater than
the thickness of the plate in order to provide a relatively close
tolerance fit of the bolt in the slot to prevent undue looseness in
the sliding action. This prevents the door securer from being
worked loose by repeated jiggling of the secured door. As the force
of gravity inherently tends to keep the bolt in the lower narrow
portion of the inclined track, the effectiveness of the
relationship is apparent.
There are numerous advantages of the present invention. The door
securer can be made reasonably inexpensively because the base plate
can be formed by simply a punching operation and the bolt by a
screw machine. The fact that the device has only two basic parts
which fit together make it simple to install and remove. It is a
relatively small, lightweight device which can be easily carried in
a pocket and ready for immediate use.
The present invention lacks many of the disadvantages of the prior
art, such as being made up of multiple separate pieces which are
difficult to assemble, any one of which can be easily lost or
dropped in the dark. The invention does not injure the door or its
jamb and it does not require tools or keys for its use.
It will be apparent from the foregoing description of the
invention, in its prefered form, that it will fulfill all the
objects attributable thereto. While the invention has been
illustrated and described in considerable detail, the protection is
not to be limited to such details as have been set forth.
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