U.S. patent number 3,884,056 [Application Number 05/403,930] was granted by the patent office on 1975-05-20 for lock for sliding doors.
Invention is credited to Ora V. East, Vern A. East.
United States Patent |
3,884,056 |
East , et al. |
May 20, 1975 |
Lock for sliding doors
Abstract
This lock device consist primarily of a body portion having a
lever arm which engages a latch plate, the lever arm serving to
prevent disengagement of the latch plate when the device is in lock
position.
Inventors: |
East; Vern A. (Scottsdale,
AZ), East; Ora V. (Scottsdale, AZ) |
Family
ID: |
23597467 |
Appl.
No.: |
05/403,930 |
Filed: |
October 5, 1973 |
Current U.S.
Class: |
70/100; 292/98;
292/210; 70/DIG.52; 292/197 |
Current CPC
Class: |
E05B
65/0811 (20130101); Y10S 70/52 (20130101); Y10T
292/1092 (20150401); Y10T 292/0947 (20150401); Y10T
292/1077 (20150401); Y10T 70/5195 (20150401) |
Current International
Class: |
E05B
65/08 (20060101); E05b 065/08 () |
Field of
Search: |
;70/100,136,137,142,DIG.52
;292/96,98,100,110,124,126,129,197,200,210,224,226,229,DIG.49 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Craig, Jr.; Albert G.
Claims
What I now claim is:
1. A latch mechanism for a slidable door comprising: a hollow body,
a latch plate having lip means adapted to releasably grasp a
keeper, first pivot means pivotally supporting said latch plate
within said body, a lever arm, second pivot means pivotally
supporting said lever arm within said body, the axes of the two
pivot means being spaced and substantially parallel, said latch
plate being defined in part by a peripheral recess generally facing
toward said second pivot means and receiving the distal end of said
lever arm, said peripheral recess being shaped in such a manner as
to form a cam and follower relationship with said distal end of the
lever arm so that pivotal movement of said lever arm will cause
pivotal movement of said latch plate between a keeper grasping, or
latching, position and an unlatching position, said peripheral
recess also being shaped such that when the latch plate is in its
latching position the lever arm will be in contact with a planar
portion thereof, the planar portion lying in a plane containing the
axis of said first pivot means and being perpendicular to a second
plane containing the axis of said second pivot means and the point
of contact of the lever arm with said planar portion, so that all
external pressure applied directly to said latch plate in an
attempt to pivot it toward its unlatching position will be applied
through said lever arm directly to said second pivot means,
manually accessible means for pivoting said lever arm, and stop
means fixedly carried within said body and limiting pivotal
movement of said lever arm in one direction to that position
wherein the distal end thereof abuts said planar portion of said
peripheral recess of said latch plate.
2. A latch mechanism as defined in claim 1 wherein said first pivot
means includes a pin secured within said hollow body and snugly
passing through the only opening through said latch plate.
3. A latch mechanism as defined in claim 1 wherein said second
pivot means includes a cylinder fixedly secured to said lever arm
with opposite ends thereof extending through opposed walls of said
hollow body and said manually accessible means includes a key
operated cylinder lock interconnected with one end of said
cylinder.
4. A latch mechanism as defined in claim 3 wherein said manually
accessible means further includes a thumb turn type of knob
interconnected with the other end of said cylinder.
5. A latch mechanism as defined in claim 1 wherein said stop means
is in the nature of a pin extend across said hollow body and
secured to opposed walls thereof.
6. A latch mechanism as defined in claim 1 wherein said hollow body
is adapted to be supported within a mortise in an edge of a stile
of a slidable door.
Description
This invention relates to door locks, and more particularly to a
lock for sliding doors.
It is therefore the principal object of this invention to provide a
lock for sliding doors which will be of such structure, so as to
prevent disengagement of the lock with a rhythmic motion of a bar
on to the door a practice common in the unauthorized opening of
sliding doors leading to a patio or balcony.
Another object of this invention is to provide a lock which will
have spring loaded lever arm means which will prevent the
disengagement of a latch plate when the door is locked.
A further object of this invention is to provide a lock of the type
described, of which the lever arm will serve as a prop for the
latch plate when the door is locked, the lock body including a stop
pin so as to prevent overthrow of the lever arm.
A further object of this invention is to provide a two component
latching device, the components being kept in proper relation to
each other by an open recess in one component, namely the latch
plate, receiving an end of the other component, namely the lever
arm.
A further object of this invention is to provide a latching device
including two independently pivotally mounted components, one being
a latch plate with a conventional lip for engagement with a keeper
or strike plate and the other being a lever arm serving as a prop
for the latch plate when in the latching position.
A further object of this invention is to provide a latching device
including two main components independently mounted with no
mechanical linkage tying the two components together, one component
being a lever arm, and further including a stop pin to limit travel
of the lever arm to its latching position and a conventional
overcenter loading spring to exert pressure on the lever arm
against the stop pin.
A further object is to provide a latching device including two
pivotally supported components whose pivot points and point of
mutual contact form a 90.degree. angle that is not altered by any
means other than key or thumb turn operation, the bearing point not
being altered by wear.
A further object is to provide a latching device including a latch
plate and a lever arm, the latch plate being of solid construction,
not being sliced, drilled or mutilated in any way by removal of
metal for a mechanical tie with the lever arm thus maintaining
sufficient strength to eliminate the necessity of any type of
reinforcing device to save the structure from damage.
Other objects of the invention are to provide a lock which has a
minimum number of parts, is simple in design, inexpensive to
manufacture, rugged in construction, of such size and strength as
to prevent damage by shock in use or misuse, easy to use and
efficient inoperation.
These and other objects will be readily evident upon a study of the
following specification and the accompanying drawing, wherein:
FIG. 1 is a cross-sectional view taken along the line 1--1 of FIG.
3;
FIG. 2 is similar to FIG. 1, but shows the device in open
position;
FIG. 3 is a rear end view of the device;
FIG. 4 is a fragmentary end view of a door showing the device
installed thereon.
According to this invention, a lock 10 is shown to have a body 11
with spacers 12 having openings 13 the openings 13 provide for the
entrance of threaded bolt fasteners that will hold the inside and
outside handles of the lock 10, together.
A pivotable latch plate 14 is carried upon pin 15. Latch plate 14
includes a lip 14a defined by a recess 16 and the opposite end of
latch plate 14 includes a lip 17 defined by recess 18. The lip 14a
of latch plate 14, serves to engage the keeper or strike plate 15a
mounted to the door jamb 15b. A pivotable lever arm 19 is secured
fixedly to member 20 of the lock cylinder, and member 20 includes a
retangular slot 20a. A pin 21 through member 20, carries a rod 22
which is encompassed by means of a coiled spring 23, the rod 22
also extending through pin 24.
Looking now at FIGS. 1 and 2 of the drawing, it will be seen that
body 11 of lock 10, is provided with a stop pin 25 against which
lever arm 19 abuts when lock 10 is closed.
The lock cylinder (not shown) has a stem engaging lever arm 19 by
means of the slot 20a, the stem also connecting with thumb turn
type of knob or handle 26.
It will be seen that the spring 23 serves as means for adding
pressure to the end of lever arm 19 in both, the open and closed
positions.
It shall be noted that the particularly lock design herein
described, makes possible for the shortest opening in the door
stile in which the lock 10 is inserted.
Referring again to FIG. 1 of the drawing, it will be seen that one
end of lever arm 19 engages the periphery of the recess 18, thus
preventing the rotation of latch plate 14 and the disengagement of
the lip 14a from the keeper or strike plate 15a secured to the door
jamb 15b.
It shall also be noted that lock 10 is adaptable to various types
of existing handles, by making small variations in the design of
the components herein described, however, the principal of
operation remains the same.
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