U.S. patent number 3,699,788 [Application Number 05/114,991] was granted by the patent office on 1972-10-24 for latch construction including assembly, anti-violation and dead bolt features.
This patent grant is currently assigned to Emhart Corporation. Invention is credited to John R. Gerlach, Clarence B. Morrensen.
United States Patent |
3,699,788 |
Gerlach , et al. |
October 24, 1972 |
LATCH CONSTRUCTION INCLUDING ASSEMBLY, ANTI-VIOLATION AND DEAD BOLT
FEATURES
Abstract
A bolt is moved by a driving lever pivoted on the bolt and
through a transverse pin to a slotted rotatable driving member, the
driving lever pin being guided in movement in the driving member
slot by extension thereof transversely through an inverted U-shaped
guide slot in the latch frame. The forward downward end portion of
the guide slot is rearwardly undercut in its downward extension.
The operating lever is rotatable through a transverse driving shaft
transversely slidably engaged therewith, the driving shaft being,
in turn, rotated through a key operated lock cylinder connected to
the shaft through a usual lost motion arrangement. The driving
shaft is D-shaped cross section engageable in a D-shaped cross
section opening of the driving member. Anti-violation plates of
unique form are positioned beneath usual rosette and cover plates
resisting shearing of the lock cylinder frame.
Inventors: |
Gerlach; John R. (Monterey
Park, CA), Morrensen; Clarence B. (Orange, CA) |
Assignee: |
Emhart Corporation (Bloomfield,
CT)
|
Family
ID: |
22358685 |
Appl.
No.: |
05/114,991 |
Filed: |
February 12, 1971 |
Current U.S.
Class: |
70/134; 70/381;
292/139; 70/417 |
Current CPC
Class: |
E05B
63/0017 (20130101); Y10T 70/7723 (20150401); Y10T
70/5341 (20150401); Y10T 70/7921 (20150401); Y10T
292/1015 (20150401) |
Current International
Class: |
E05B
63/00 (20060101); E05b 009/04 (); E05c
001/06 () |
Field of
Search: |
;70/129,134,379,380,381,471,DIG.42
;292/26,36,48,82,97,123,139,158,167,196,223,233 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
Primary Examiner: Craig, Jr.; Albert G.
Claims
We claim:
1. In a latch construction of the type having a longitudinally
slidable reciprocal bolt movable forwardly and rearwardly into
extended and retracted positions by a generally longitudinally
extending driving lever, a forward end of said driving lever being
pivotally connected to said bolt pivotal upwardly and downwardly
about a transverse axis, a driving member rotatable about a
transverse axis having a generally radially extending and
transversely opening driving slot formed therein, a transverse
driving pin through a rearward end of said driving lever and
through said driving member driving slot slidable along said
driving slot, said driving pin also extending through and being
slidable along a guide slot formed in and opening transversely of a
latch frame member, said guide slot having a longitudinally
extending portion terminating at least forwardly in a generally
downwardly projecting end, said driving pin sliding along said
guide slot longitudinally extending portion during reciprocal
movement of said bolt by rotation of said driving member and moving
downwardly into said guide slot forward end when said bolt is moved
fully into its extended position; the improvements in combination
therewith: said guide slot forward end including a rear wall
undercut rearwardly from connection of said guide slot
longitudinally extending portion dimensioned and located at least
partially receiving said driving pin when said bolt is moved fully
into its extended position resisting movement of said driving pin
upwardly out of said guide slot forward end and rearwardly along
said guide slot longitudinally extending portion when an outside
rearward force is applied to said bolt tending to urge said bolt
rearwardly from its fully extend position.
2. A latch construction as defined in claim 1 in which said rear
wall undercut of said guide slot forward end is formed by said rear
wall being rearwardly downwardly angled from said guide slot
longitudinally extending portion.
3. A latch construction as defined in claim 1 in which said guide
slot longitudinally extending portion terminates rearwardly in a
generally downwardly projecting rearward end receiving said driving
pin when said bolt is moved fully into its retracted position.
4. A latch construction as defined in claim 1 in which resilient
means is operably connected to said driving lever for constantly
resiliently urging said driving lever rearward end downwardly
tending to urge said driving pin downwardly into and retain said
driving pin in said guide slot forward end when said bolt is moved
into its fully extended position.
5. A latch construction as defined in claim 1 in which resilient
means is at said driving lever forward end effective spaced
rearwardly of said driving lever forward end pivotal connection to
said bolt for constantly resiliently urging said driving lever
rearward end downwardly tending to urge said driving pin downwardly
into and retain said driving pin in said guide slot forward end
when said bolt is moved into its fully extended position.
6. A latch construction as defined in claim 1 in which resilient
means overlies said driving lever forward end bearing downwardly
spaced rearwardly of said driving lever forward end pivotal
connection to said bolt for constantly resiliently urging said
driving lever rearward end downwardly tending to urge said driving
pin downwardly into and retain said driving pin in said guide slot
forward end when said bolt is moved into its fully extended
position.
7. A latch construction as defined in claim 1 in which a leaf
spring is mounted at said driving lever forward end extending
rearwardly along said driving lever, said leaf spring including a
transverse portion overlying said driving lever spaced rearwardly
of said driving lever forward end pivotal connection to said bolt,
said leaf spring at least through said transverse portion thereof
constantly resiliently urging said driving lever rearward end
downwardly tending to urge said driving pin downwardly into and
retain said driving pin in said guide slot forward end when said
bolt is moved into its fully extended position.
8. A latch construction as defined in claim 1 in which said rear
wall undercut of said guide slot forward end is formed by said rear
wall being rearwardly downwardly angled from said guide slot
longitudinally extending portion; and in which resilient means is
operably connected to said driving lever constantly resiliently
urging said driving lever rearward end downwardly tending to urge
said driving pin downwardly into and retain said driving pin in
said guide slot forwardly end within said undercut formed by said
rearwardly downwardly angling of said guide slot forward end when
said bolt is moved into its fully extended position.
9. A latch constrution as defined in claim 1 in which said rear
wall undercut of said guide slot forward end is formed by said rear
wall being rearwardly downwardly angled from said guide slot
longitudinally extending portion; in which said guide slot
longitudinally extending portion terminates rearwardly in a
generally downwardly projecting end receiving said driving pin when
said bolt is moved rearwardly to its fully retracted position; and
in which resilient means is operably connected to said driving
lever constantly resiliently urging said driving lever rearward end
downwardly tending to urge said driving pin downwardly into and
retain said driving pin in said guide slot forward end and within
said undercut formed by said rearwardly downwardly angling of said
rear wall of said guide slot forward end when said bolt is moved
into its fully extended position, said resilient means through said
constant resilient urging of said driving lever rearward end
downwardly also tending to urge said driving pin downwardly into
and retain said driving pin in said guide slot rearward end when
said bolt is moved into its fully retracted position.
10. A latch construction as defined in claim 1 in which said rear
wall undercut of said guide slot forward end is formed by said rear
wall being rearwardly downwardly angled from said guide slot
longitudinally extending portion; and in which resilient means is
operably connected to said driving lever forward end effective
spaced rearwardly of said driving lever forward end pivotal
connection to said bolt for constantly resiliently urging said
driving lever rearward end downwardly tending to urge said driving
pin downwardly into and retain said driving pin in said guide slot
forward end received within said undercut formed by said rearwardly
downwardly angling of said rear wall of said guide slot forward end
when said bolt is moved into its fully extended position.
11. In a latch construction of the type having a longitudinally
slidable reciprocal bolt movable forwardly and rearwardly into
extended and retracted positions by a generally longitudinally
extending driving lever, a forward end of said driving lever being
pivotally connected to said bolt pivotal upwardly and downwardly
about a transverse axis, a driving member rotatable about a
transverse axis having a generally radially extending and
transversely opening driving slot formed therein, a transverse
driving pin through a rearward end of said driving lever and
through said driving member driving slot slidable along said
driving slot, said driving pin also extending through and being
slidable along a guide slot formed in an opening transversely of a
latch frame member, said guide slot having a longitudinally
extending portion terminating at least forwardly in a generally
downwardly projecting end, said driving pin sliding along said
guide slot longitudinally extending portion during reciprocal
movement of said bolt by rotation of said driving member and moving
downwardly into said guide slot forward end when said bolt is moved
fully into its extended position; the improvements in combination
therewith; resilient means at said driving lever forward end
effective spaced rearwardly of said driving lever forward end
pivotal connection to said bolt for constantly resiliently urging
said driving lever rearward end downwardly tending to urge said
driving pin downwardly into and retain said driving pin in said
guide slot forward end when said bolt is moved into its fully
extended position.
12. A latch construction as defined in claim 11 in which said
resilient means overlies and bears resiliently downwardly against
said driving lever forward end.
13. A latch construction as defined in claim 11 in which said
resilient means includes a leaf spring operably connected to said
bolt and extending rearwardly adjacent said driving lever forward
end, said leaf spring having at least a part thereof transversely
overlying said driving lever forward end engaging said driving
lever forward end spaced rearwardly of said driving lever forward
end pivotal connection to said bolt
14. A latch construction as defined in claim 11 in which said
resilient means includes a leaf spring operably connected to said
bolt having transversely spaced and longitudinally extending
portions extending rearwardly transversely adjacent said driving
lever, said leaf spring longitudinally extendingportions
terminating rearwardly in a transverse portion extending
therebetween and overlying said driving lever spaced rearwardly of
said driving lever forward end pivotal connection to said bolt.
15. A latch construction as defined in claim 11 in which said
resilient means is a leaf spring including a lower portion
underlying said driving lever forward end and extending forwardly
into said bolt, a forward portion forward of said driving lever
forward end and within said bolt, an upper portion extending
rearwardly from within said bolt adjacent said driving lever
forward end and having at least a part thereof overlying said
driving lever forward end spaced rearwardly of said driving lever
forward end pivotal connection to said bolt.
16. A latch construction as defined in claim 11 in which said
resilient means is a leaf spring including a lower portion
underlying said driving lever forward end and extending forwardly
into said bolt, a forward portion forward of said driving lever
forward end and within said bolt, an upper portion comprised of
transversely spaced and longitudinally extending parts extending
rearwardly from within said bolt transversely adjacent said driving
lever forward end, said upper portion parts terminating rearwardly
in a transversely extending part connected transversely
therebetween and overlying said driving lever forward end spaced
rearwardly of said driving lever forward end pivotal connection to
said bolt.
17. In a latch construction of the type for mounting in doors and
the like with a bolt extendable from a door edge, a latch driving
mechanism mounted within the door operably connected to said bolt
movable for moving said bolt between extended and retracted
positions, an exterior operator projecting outwardly from an
exterior door face including a lock frame mounting a lock cylinder
telescoped by a surrounding annular cover inwardly abutting said
exterior door face, an interior operator projecting outwardly from
an interior door face including an annular cover inwardly abutting
said interior door face, said exterior and interior operators being
operably connected to said latch driving mechanism for selectively
moving said latch driving mechanism, and fastening means engaged
between said lock frame of said exterior door operator and said
interior operator retaining assembly of said exterior and interior
operator with said latch driving mechanism and said door; the
improvements comprising: a thickened, hardened metal, annular guard
plate in said exterior operator telescoping said lock frame between
said lock frame and said cover totally exteriorly covered by said
cover, said guard plate inwardly abutting said door exterior face
and projecting inwardly of said door to spaced inwardly of said
door exterior face surrounding said lock frame and said fastening
means both inwardly and outwardly of said door exterior face, said
guard plate being free of connection to said lock frame and door
other than said telescoping and abutment, said guard plate through
said telescoping and abutment of said lock frame and door being
rotatable relative thereto.
18. A latch construction as defined in claim 17 in which said guard
plate extends outwardly substantially coextensive with said
exterior operator lock frame; and in which said exterior operator
cover is free of connection to said lock frame and door other than
said telescoping and abutment, said cover being rotatable relative
to all of said guard plate, lock frame and door.
19. A latch construction as defined in claim 17, in which a
thickened, annular guard plate is positioned in said interior
operator inwardly of said interior operator cover inwardly abutting
said interior door face, said interior operator guard plate
extending across between said door interior face and said fastening
means engagement with said interior operator to at least adjacent
said fastening means inwardly supporting said interior operator
cover and said fastening means at said interior operator.
20. A latch construction as defined in claim 17 in which said guard
plate extends outwardly substantially co-extensive with said
exterior operator lock frame; in which a thickened, annular guard
plate is positioned in said interior operator inwardly of said
interior operator cover inwardly abutting said interior door face,
said interior operator guard plate extending across between said
door interior face and said fastening means engagement with said
interior operator to at least adjacent said fastening means
inwardly supporting said interior operator cover and said fastening
means at said interior operator; and in which said exterior
operator cover is free of connection to said lock frame and door
other than said telescoping and abutment, said cover being
rotatable relative to all of said guard plate, lock frame and door.
Description
BACKGROUND OF THE INVENTION:
This invention relates to an improved latch construction including
assembly, anti-violation and dead bolt features, and more
particularly, to a latch construction having maximum relative
simplicity, yet which may include a novel dead bolt arrangement
positively assuring the retainment of the bolt in extended position
and against an exterior force being applied thereagainst in an
attempt to move the bolt toward retracted position, as well as
novel assembly and anti-violation arrangements which prevent
improper assembly of the latch construction when the latch is used
with a lock cylinder operating mechanism and prevent shearing in
violation attempts of the lock cylinder frame. In the latch
construction with the novel dead bolt arrangement, a normal, single
dead bolt is used, not requiring the additional auxiliary dogging
heretofore necessary, and the dogging is produced inherently in the
interior operating mechanism by relatively inexpensive additions.
Furthermore, certain of the internal latch operating mechanism
elements are of improved form and where the novel dead bolt feature
is included, will operate therewith to produce maximum dead bolt
dogging characteristics. Still further, the novel assembly
arrangement is also internally of the latch operating mechanism
assuring that important operational parts can only be assembled in
a proper relationship, but still requiring merely conventional
assembly procedures, and the anti-violation means resists shearing
and other attacks of the lock cylinder frame, common in violation
attempts.
Various prior latch constructions have been provided having dogging
mechanisms integrated therein. The most common form includes a main
reciprocal biased bolt retracted by operation of the latch
mechanism through various forms of lock cylinders and operating
knobs along with an auxiliary dogging lever positioned adjacent the
main bolt and normally reciprocal therewith, but additionally
independently reciprocal relative to the main bolt. The auxiliary
dogging lever is, in turn, connected to a main bolt locking
mechanism which either through direct main bolt engagement or latch
operating element engagement locks the main bolt in extended
position when the auxiliary dogging lever is in a retracted
position.
Still in this auxiliary dogging lever arrangement, the latch
construction is mounted properly positioned so that the auxiliary
dogging lever is at the side of the main bolt facing, say, the
interior side of a door in which the latch construction is
installed so that the auxiliary dogging lever is sheltered from
access from the exterior side of the door, particularly when the
main bolt is in extended position at the line of separation between
the door and the door jamb. The usual strike plate installed in the
door jamb has the usual bolt opening therein for receiving the main
bolt when the main bolt is biased outwardly to extended position
for retaining the door closed, and when the auxiliary dogging lever
form of latch construction is used, the strike plate bolt opening
remains the same size so as to receive the main bolt therein in
extended position in usual manner, but not receiving the auxiliary
dogging lever therein, placing it in a main bolt dogging position.
This usual form of main bolt dogging, although satisfactory, is
quite expensive to provide.
A still further problem encountered in the modern society is one
involved with the increase in attempts to illegally violate the
keyed exterior operators, the lock cylinders and lock cylinder
frames, of latch constructions in order to gain illegal entry to
areas guarded thereby. The more common methods applied are to exert
transverse pounding to the lock cylinder frames to destry the same
or shearing off the lock cylinder frame and lock cylinder by large
shearing means. In either case, the principal area of attack is in
a transverse plane directly between the latch construction exterior
rosette plate and the exterior surface of the door upon which the
latch construction is mounted. Thus increased rigidity and guarding
of this area of the latch constructions is vitally needed.
OBJECTS AND SUMMARY OF THE INVENTION:
It is, therefore, an object of this invention to provide an
improved latch construction including assembly, anti-violation and
dead bolt features wherein merely a conventional bolt is required,
yet with relatively minor, but novel, changes in the latch
operating mechanism improved dogging qualities are integrated
therein which assure that when the bolt is placed in extended
position, whether engaged with a door jamb strike plate or
otherwise, it cannot be moved toward disengaged position from an
exterior force without a virtual destruction of the latch operating
mechanism. In the improved latch construction of the present
invention, the latch operating mechanism includes an operating or
driving lever forwardly pivotally connected to the bolt and
rearwardly connected to a slotted, rotatable, operating or driving
member through a driving pin which also extends through a unique
guide slot of the latch stationary frame. During the main part of
the bolt movement by the latch operating mechanism, this driving
pin moves forwardly and rearwardly in the guide slot while
transferring the rotatable motion of the driving member to the
driving lever and bolt, but at either extremity of such forward and
rearward movement, the driving pin moves into an offset of the
guide slot positively finally positioning the bolt in its extended
and retracted positions.
Although the mere end extremity offsets of the guide slot do tend
to retain the bolt through the driving lever and driving pin in its
particular extended or retracted position until purposely moved
therefrom by the latch operating mechanism, true bolt dogging
features in the bolt extended position are not present if the
exterior force against the bolt tending to move it to retracted
position is of any magnitude, particularly of the impacting type.
The novel bolt dogging arrangement is, therefore, completed by
forming the end extremity offset of the guide slot receiving the
driving pin when the bolt is in extended position having an
undercut therein receiving the driving pin and retaining the same
therein unless purposely moved therefrom by the usual actuation of
the latch operating mechanism. Thus, with the bolt in extended
position and the driving pin within the undercut of the end
extremity offset in the guide slot, any outside force directly
against the extended bolt tending to move such bolt toward
retracted position will only tend to move the driving pin deeper
into the overhang and against movement from the end extremity
offset of the guide slot so as to provide dogging protection for
the bolt.
It is a further object of this invention to provide an improved
latch construction including assembly, anti-violation and dead bolt
features wherein a novel spring arrangement in the latch operating
mechanism combines with the previously described driving lever of
such latch operating mechanism to assure that proper and complete
bolt extension and retraction can take place whether or not the
latch construction includes the foregoing bolt dogging features,
but where the dead bolt improvements are included, this novel
spring arrangement additionally acts to greatly augment the
positive action of the bolt dogging improvements. In the preferred
embodiment of the present invention, the spring is arranged to
continuously resiliently urge the driving lever into proper sliding
surface contact with the guide slot and particularly resiliently
urging the driving pin into the end extremity offsets of the guide
slot when the bolt reaches either of its extended and retracted
positions. The spring, thereby, constantly resiliently urges
retention of the driving pin guide slot offset positioning and with
the bolt dogging feature will always assure that the driving pin is
received securely within the overhang of the guide slot extremity
when the bolt is in its extended position.
It is still a further object of this invention to provide an
improved latch construction including assembly, anti-violation and
dead bolt features in which, when the latch construction includes a
key actuated lock cylinder for operation thereof, a novel single
position, assembly connection between the lock cylinder connected
driving shaft and the driving member of the latch construction
assures that the latch construction can only be assembled during
installation thereof in a proper manner. As hereinbefore discussed,
with lock cylinders of the type wherein the operating keys thereof
are only removable in a neutral position, proper escapements in key
movements must be included by use of lost motion connections
between the lock cylinder and the latch operating or driving shaft.
The single position connection between the driving shaft and
driving member thereby prevents improper assembly since the driving
lever and driving member can only be assembled in the single
position proper relationship.
It is also an object of this invention to provide an improved latch
construction including assembly, anti-violation and dead bolt
features wherein specifically shaped, relatively shear resistant
and relatively rigid, anti-violation guards may be added to the
prior latch assemblies without other alteration thereto and will
resist the more common forms of illegal violation of latch
constructions. According to a preferred embodiment of the present
invention, a specifically formed, thick and rigid, guard plate is
positioned beneath the usual exterior latch rosette and lock
cylinder cover plates, telescoping the lock cylinder assembly and
projecting inwardly of the exterior latch mounting surface, usually
an exterior door surface. A specifically formed, thick and rigid,
guard plate is also installed beneath the interior rosette and
cover plates, particularly supporting the latch securing screws. As
a result, the exterior guard plate resists transverse shearing and
transverse impacts in attempts to sever the lock cylinder frame and
lock cylinder from the latch assembly, particularly guarding the
plane of the exterior latch mounting surface or exterior door
surface, while the interior guard plate resists latch construction
deformation around the latch supporting screws which could, in
turn, loosen the latch construction mounting and expose the lock
cylinder frame and lock cylinder at the plane of the exterior latch
mounting surface.
It is an additional object of this invention to provide an improved
latch construction including assembly, anti-violation and dead bolt
features which satisfies all of the foregoing objects in a
relatively simple manner adding the described new and novel
advantageous improvements, yet at only nominal added cost over
similar latch constructions not including such improvements. In the
case of the bolt dogging features, the greater security of the
relatively expensive bolt dogging type of latch constructions is
provided, yet at a minimum increase cost over latch constructions
not including any bolt dogging features. Furthermore, the assembly
features provide greater assembly convenience absolutely demanding
correct assembly of the latch construction, but yet the assembly
may take place still using conventional assembly procedures and
without any increased assembly labor costs. As to the
anti-violation features, the same are simply shaped, added parts
interfitting in the previous assemblies without alteration thereto,
again minimizing manufacturing costs.
Other objects and advantages of the invention will be apparent from
the following specification and the accompanying drawings which are
for the purpose of illustration only.
BRIEF DESCRIPTION OF THE DRAWINGS:
FIG. 1 is a horizontal sectional view of a first embodiment of the
latch construction of the present invention installed in a door,
the door being shown in fragmentary horizontal section, and the
latch construction being shown with the bolt thereof in retracted
position;
FIG. 2 is a side elevational view of the latch construction of FIG.
1 removed from the door, the bolt thereof in the full line showing
being in retracted position within the latch frame and the lock
cylinder key being in neutral position, phantom lines showing the
bolt extended with the relative rotative position of the key, all
looking in the direction of the arrows 2--2 in FIG. 1;
FIG. 3 is a view similar to FIG. 2, but with the full line showing
of the bolt in extended position with the key in neutral position,
phantom lines showing the bolt approaching retracted position and
the relative key positioning;
FIG. 4 is a vertical sectional view looking in the direction of the
arrows 4--4 in FIG. 1, but with the latch construction again
removed from the door;
FIG. 5 is a fragmentary, vertical sectional view similar to FIG. 4,
with the bolt in extended position and parts removed for more
clearly showing various operating elements of the latch
construction;
FIG. 6 is a fragmentary top plan view of the latch construction as
shown in FIG. 5;
FIG. 7 is a view similar to FIG. 5, but with the bolt in an
intermediate position between extended and retracted positions;
FIG. 8 is an enlarged, vertical sectional view looking in the
direction of the arrows 8--8 in FIG. 7;
FIG. 9 is an enlarged, fragmentary, horizontal sectional view
looking in the direction of the arrows 9--9 in FIG. 7;
FIG. 10 is an enlarged, fragmentary, horizontal sectional view
looking in the direction of the arrows 10--10 in FIG. 7;
FIG. 11 is a horizontal sectional view similar to FIG. 1 of a
second embodiment of the latch construction of the present
invention;
FIG. 12 is a vertical sectional view of the latch construction of
FIG. 11 looking in the direction of the arrows 12--12 in FIG. 11;
and
FIG. 13 is a vertical sectional view looking in the direction of
the arrows 13--13 in FIG. 11.
DESCRIPTION OF THE BEST EMBODIMENT CONTEMPLATED:
Referring to the drawings, a first embodiment of the improved latch
construction of the present invention is shown therein, in FIG. 1
as mounted in operative position in a door and in FIGS. 2 through
10 in the assembled position, but removed from the door. The latch
construction illustrated may be formed of usual material and by
usual manufacturing procedures. Furthermore, the particular
construction of latch illustrated is broadly of a usual type
constructed for exterior key operation and interior hand
operation.
More particularly, the first embodiment latch construction includes
a stationary latch frame generally indicated at 20 mounting a
forwardly and rearwardly reciprocal bolt 22 movable forwardly to an
extended position as shown, for instance, in FIGS. 3, 5 and 6, and
movable rearwardly to a retracted position as shown, for instance,
in FIGS. 1, 2 and 4. The forward and rearward movement of the bolt
22 toward and to its extended position and toward and to its
retracted position in the longitudinally reciprocal movement is
provided by a latch operating or driving mechanism generally
indicated at 24 partially contained transversely between
transversely spaced rearward extensions 26 of the latch frame 20
and partially extending transversely through said rearward
extensions, the driving movement of the latch operating mechanism
being supplied by a keyed exterior operator generally indicated at
28 and a hand interior operator generally indicated at 30. The
latch construction is mounted in usual manner in a conventional
door generally indicated at 32 with the keyed exterior operator at
an exterior side 34 of the door, and hand interior operator 30 at
an interior side 36 of the door and the bolt 22 longitudinally
extendable through an edge 38 of the door into a usual strike plate
(not shown) of a usual door jamb (not shown).
As can be clearly seen in FIGS. 4, 5, and 7 through 10, the bolt 22
is formed at the rearward end thereof with transversely opposed and
opening recesses 40 which also open rearwardly to provide a
connecting lug 42 therebetween. The bolt recesses 40 are generally
rectangular in side elevation as shown in FIGS. 5, and 7, although
being slightly upwardly angularly relieved at rearward ends thereof
for a purpose to be hereinafter pointed out. Thus, the rearward
portion of the bolt 22 both underlies and overlies the recesses 40
despite the transverse and rearward opening of such recesses.
The latch operating or driving mechanism 24 includes a pair of
transversely spaced and longitudinally forwardly and rearwardly
extending operator or driving levers 44 having the forward ends
thereof projecting forwardly into the bolt recesses 40 at opposite
sides of the bolt connecting lug 42 and upwardly and downwardly
pivotly connected to the bolt connecting lug by a pivot pin 46. A
unique, generally C-shaped, leaf-type spring 48 is slidably
forwardly received within the bolt recesses 40 having generally
C-shaped side portions 50 lying transversely adjacent the forward
ends of the driving levers 44 with said side portions being joined
transversely beneath the forward ends of the driving levers 44 by a
lower bar portion 52 and being joined above the driving lever
forward ends by an overlying upper bar portion 54. Both of the
spring lower and upper bar portions 52 and 54 are spaced rearwardly
of the bolt connecting lug 42 with the spring side portions 50
lying against the walls of the bolt recesses 40 except at the
previously mentioned angular relief of the recesses. The spring
upper bar portion 54 bears resiliently downwardly against the
forward ends of the driving levers 44 spaced rearwardly of the
connecting pivot pin 46 so as to normally urge the driving levers
44 to pivot downwardly but permitting upward movement thereof
within the confines of said recess angular relief.
The driving levers 44 of the latch driving mechanism 24 project
longitudinally rearwardly transversely spaced apart and
transversely between the rearward extensions 26 of the latch frame
20 with the driving lever rearward ends terminating rearwardly
oppositely transversely adjacent a radial projection 56 of a
transversely extending and rotatable operating or driving member
58. The radial projection 56 of the driving member 58 has a
radially extending driving slot formed transversely therethrough
receiving a transverse driving pin 60 radially slidable, as well as
relatively pivotal, therein. The driving pin 60 extends oppositely
transversely through the rearward extremities of the driving levers
44 and continues oppositely transversely through guide slots 62
formed transversely through the opposite rearward extensions 26 of
the latch frame 20.
The guide slots 62 of the latch frame rearward extensions 26 are,
of course, transversely aligned receiving the driving pin 60
pivotal therein and slidable therealong. Furthermore, these guide
slots 62 include main longitudinally extending portions 64
extending generally straight forwardly and rearwardly terminating
rearwardly in generally downwardly projecting rearward ends 66 and
terminating forwardly in generally downwardly projecting forward
ends 68. Particularly important to certain of the principles of the
present invention is the fact that rear walls 70 of the guide slot
forward ends 68 are downwardly rearwardly angled in the downward
progression of the guide slot forward ends so that these rear walls
70 downwardly progressively underlie the guide slot longitudinal
portions 64 thereby forming forward end undercuts or overhangs as
particularly shown in FIGS. 4, 5 and 7. At the same time, it will
be noted that the guide slot rearward and forward ends 66 and 68
project sufficiently downwardly from the guide slot longitudinal
portions 64 so that the driving pin 60 may be received fully
downwardly therein when the bolt 22 and the driving levers 44 are
at either of their forward and rearward extremities of
movement.
The driving member 58 of the latch driving mechanism 24 extends
transversely through and between the latch frame rearward
extensions 26 being rotatably mounted thereby and projects
transversely oppositely outwardly of the latch frame rearward
extensions. Furthermore, the driving member 58 has a D-shaped cross
section opening 72 formed transversely therethrough, in the
particularly relative relationships shown, this D-shaped opening
showing an upright D-shape when the bolt 22 is in retracted
position and an upwardly projecting D-shape when the bolt is in
extended position as shown in FIGS. 4 and 5, respectively. Still
further, the D-shaped opening 72 of the driving member 58
transversely slidably receives a mating D-shaped cross section,
transversely extending driving shaft 74 therethrough during
assembly of the latch driving mechanism 24 thereby providing the
driving member 58 and the D-shaped driving shaft 74 exactly
rotatably engaged in one predetermined relative relationship,
important to certain of the principles of the present invention as
will be hereinafter explained. Spaced transversely from the driving
member 58, the driving shaft 74 is particularly engaged at the one
side with the keyed exterior operator 28 and at the other side with
the hand interior operator 30.
Referring particularly to FIG. 1, the keyed exterior operator 28
and the hand interior operator 30 are secured at the exterior and
interior sides 34 and 36 of the door 32 transversely oppositely
against similar rosette plates or covers 76 by threaded studs 78
projecting transversely from the keyed exterior operator and
through the latch frame rearward extensions 26 free of interference
with the driving levers 44 engaged by securing screws 80 from the
hand interior operator 30. The keyed exterior operator 28 is
generally of usual, well-known construction including an outer lock
cylinder cover 82 telescoping a stationary lock cylinder frame 84
which, in turn, rotatably mounts a keyed lock cylinder 86. The lock
cylinder 86, again, is of usual form having a diametrical key slot
88 receiving a particularly formed key 90 arranged for rotating the
lock cylinder relative to the lock cylinder frame 84 in the usual
manner, and the lock cylinder is further formed so that the key is
captive in the key slot and cannot be removed therefrom in all
rotative positions of the lock cylinder except a neutral position
shown in full lines in FIGS. 2 and 3 wherein the key slot is
exactly vertical. It should be pointed out that this vertical
position of the key slot 88 in which the key 90 may be removed is a
single vertical position and when the key slot is rotated
180.degree. to be vertical, but upended, the key is still retained
captive, only being removable in the single position.
The keyed lock cylinder 86 through a well-known construction
thereof is connected to the D-shaped driving shaft 74 by a
particular lost motion connection such that when the key 90 is in
the neutral position, the key and lock cylinder must be moved a
certain degree of rotation in either direction before rotating the
D-shaped driving shaft 74 of the latch driving mechanism 24, the
purpose thereof being to provide escapement for the key. This can
be more clearly understood by first observing the particular
positions of the D-shaped driving shaft 74 shown in FIGS. 4 and 5,
it being noted that movement of the D-shaped driving shaft for, in
turn, moving the bolt 22 from the retracted position of FIG. 4 to
the extended position of FIG. 5 is essentially one-quarter turn.
Now referring to FIG. 2, it is seen that the key 90 first moves
approximately one-eighth turn counter-clockwise in lost motion and
then the one-quarter turn to move the bolt from retracted to
extended positions as shown in phantom lines. Referring to FIG. 3,
the key 90, with the bolt in extended position, must be moved from
its neutral position first one-quarter turn in lost motion and then
one-quarter turn rotating the D-shaped driving shaft 74 to fully
retract the bolt, the bolt being shown partially retraced in
phantom lines with the corresponding relative position of the key
in phantom lines although final full bolt retraction will position
the key rotated a full one-half turn.
The purpose of this lost motion connection between the lock
cylinder 86 and the D-shaped driving shaft 74 is so that the bolt
22 may be moved fully between its extended and retracted positions,
yet at the end of such bolt movement by the key, the key may be
returned to its neutral position for removal from the lock
cylinder. As shown in FIG. 2, after the key 90 has moved
approximately three-eighths turn counter-clockwise to fully extend
the bolt 22, the key must be freely movable back to its neutral
position shown in full lines without disturbing the bolt
positioning so that the key can be removed with the bolt remaining
in its extended position. Likewise, as shown in FIG. 3, when the
bolt 22 is moved from extended to fully retracted position by
moving the key 90 one-half turn clockwise, the key must be movable
back to its neutral position shown in full lines without disturbing
the bolt positioning to permit removal of the key with the bolt in
fully retracted position. This obviously requires a minimum
180.degree. escapement for the key 90 which is the required
movement of the key during the bolt retraction operation as shown
in FIG. 3.
Although this lost motion connection between the lock cylinder 86
and the driving shaft 74 providing the minimum 180.degree.
escapement for the key 90 is old in the art, it has presented a
major difficulty during the mounting and the assembly of the prior
latch constructions which difficulty is eliminated by the improved
D-shaped driving shaft 74 engaged with the D-shaped opening 72 of
the driving member 58 of the present invention. With this lost
motion connection between the lock cylinder 86 and the driving
shaft 74, unless the driving shaft 74 is confined to only a single
assembly position with the driving member 58, it is possible to
wrongfully assemble the driving shaft with the driving member in
view of the required minimum 180.degree. escapement. In other
words, with the minimum 180.degree. escapement, the driving shaft
74 could be assembled 180.degree. wrongfully rotably positioned
with the driving member 58 requiring the latch construction to be
disassembled after original assembly to correct such error. The
D-shaped driving shaft 74 of the present invention, however, can
only be assembled with the D-shaped opening 72 of the driving
member 58 in a single correct position so that such construction
constitutes a single position assembly and eliminates the
difficulties of the prior construction.
To complete the description of the first embodiment of the latch
construction herein illustrated and described, the hand interior
operator 30 at the interior side 36 of the door 32 includes a
mounting plate or cover 92 which outwardly partially telescopes the
rosette plate or cover 76 and centrally rotably mounts a hand knob
94 projecting transversely therethrough. The hand knob 94 has an
interiorly opening, transversely extending, D-shaped cross section
recess 96 formed therein receiving a free end of the D-shaped
driving shaft 74 as such shaft passes from the D-shaped opening 72
of the driving member 58. Thus, by rotation of the hand knob 94,
the latch driving mechanism 24 may be properly moved to, in turn,
move the bolt 22 between its extended and retracted positions.
In overall operation of the first embodiment of latch construction
including the improvements of the present invention, assume that
the bolt 22 is in its fully retracted position shown in FIGS. 1, 2
and 4. In the retracted position of the bolt 22, the radial
projection 56 of the driving member 58 is rearwardly angled with
the driving pin 60 fully downwardly within the guide slot rearward
ends 66 as urged by the spring 48 through the driving levers 44.
Upon insertion and proper movement of the key 90, or the proper
movement of the hand knob 94, the driving member 58 is moved
through the driving shaft 74 to, in turn, move the radial
projection 56 of the driving member forwardly along the guide slots
62, first moving the driving pin 60 upwardly from the guide slot
rearward ends 66 flexing the spring 48 upwardly through upward
movement of the rearward extremities of the driving levers 44. As
the driving member radial projection 56 continues its forward
movement, the driving pin 60 is moved along the longitudinal
portions 64 of the guide slots 62 moving the driving levers 44 and
the bolt 22 forwardly until the bolt ultimately reaches fully
extended position at which, the driving pin 60 is forced downwardly
fully within the guide slot forward ends 68 by the downward
resilient urging of the spring 48 against the driving levers
44.
The retraction of the bolt 22 from the fully extended position as
shown in FIGS. 3, 5 and 6 to the fully retracted position as shown
in FIGS. 1, 3 and 5 is just the opposite of that hereinbefore
described. Furthermore, it will be noted that throughout the bolt
22 movement, as well as the extended and retracted stationary
positioning thereof, the spring 48 always exerts resilient pressure
downwardly agains the driving levers 44 so that the driving pin 60
is always forced to exactly follow the contours of the identical
guide slots 62. Most important, this constant downward resilient
urging of the spring 48 against the driving levers 44 insures that
the driving pin 60 will always be fully received within the guide
slot rearward and forward ends 66 and 68 at the termination of the
movements of the bolt 22. The straight downward extension of the
rearward ends 66 of the guide slot 62 tend to retain the driving
pin 60 therein and against forward movement of the driving levers
44 and the bolt 22, this holding force being augmented by the
downward resilient pressure exerted by the spring 48, thereby
positively retaining the bolt 22 in its retracted position. The
same conditions exist when the bolt 22 is fully extended with the
driving levers 44 fully forward and the driving pin 60 engaged
fully downwardly in the forward ends 68 of the guide slots 62 and
even if the guide slot forward ends 68 extended straight downwardly
similar to the guide slot rearward ends 66, a certain amount of
bolt dogging protection would be provided, that is, resistance
against rearward urging of the bolt 22 from an exterior force
directed rearwardly on the bolt itself. It has been found, however,
that if the forward ends 68 of the guide slot 62 are merely formed
straight downwardly similar to the guide slot rearward ends 66,
exteriorly applied impact blows against the bolt 22 can cause the
driving pin 60 to jump upwardly out of the guide slot forward ends
and thereby permit rearward driving of the bolt from such exterior
force.
With the uniquely formed forward ends 68 of the guide slots 62
including the downwardly rearwardly angling of the rear walls 70
thereof as previously described forming the undercuts, any force
against the bolt 22 tending to move the bolt rearwardly from its
extended position, whether impact forces or otherwise, will only
tend to force the driving pin 60 more deeply rearwardly into such
undercut. Thus, complete bolt dogging protection for the bolt 22 is
provided according to the improvements of the present invention and
this bolt dogging protection is even further augmented by the
downward resilient urging of the spring 48 against the driving
levers 44 retaining the driving pin 60 within the forward ends 68
of the guide slots 62 and within the undercuts formed by the guide
slot forward ends.
A second embodiment of the latch construction of the present
invention is shown in FIGS. 11, 12 and 13, and is identical to the
first embodiment latch construction of FIGS. 1 through 10, both as
to construction and operation thereof, with the further addition of
anti-violation means for resisting violation of the latch
construction by either the usual form of attempted shearing or
impact blows applied to exterior portions of the latch
construction, all of which will be hereinafter explained more in
detail. Thus, this second embodiment latch construction likewise
includes the latch frame generally indicated at 20 reciprocally
mounting the bolt (not shown) movable by the latch operating or
driving mechanism generally indicated at 24, which is, in turn,
selectively movable by the keyed exterior operator generally
indicated at 28 or the hand interior operator generally indicated
at 30, all operable in the same manner and for the same purposes as
hereinbefore discussed.
Furthermore, the latch construction is mounted in the door
generally indicated at 32 with the bolt (not shown) projectable
from the door edge 38, the keyed exterior operator 28 extending
outwardly from the door exterior side or face 34 and the hand
interior operator 30 extending outwardly from the door interior
side or face 36.
Still further as previously described, the keyed exterior operator
28 includes the annular rosette plate or cover 76 inwardly abutting
the door exterior face 34 and the annular lock cylinder cover 82
inwardly abutting the rosette cover 76, both of which are circular
in vertical cross-section, as shown in FIG. 13, and in combination
telescope and substantially totally exteriorly surround the lock
cylinder frame 84 and the keyed lock cylinder 86. Also, the hand
interior operator 30 includes the annular rosette plate or cover 76
inwardly abutting the door interior face 36 and the annular
mounting plate or cover 92 edgewise outwardly overlying the rosette
cover 76 rotatably mounting the hand knob 94. The exterior and
interior operators 28 and 30 are retained assembled with the latch
construction and the latch construction is retained assembled in
the door 32 by the threaded studs 78 of the exterior operator lock
cylinder frame 84 projecting inwardly through the latch driving
mechanism 24 and being threadably engaged by the securing screws 80
engaged inwardly through the interior operator mounting cover 92,
all as well shown in FIG. 11.
More particularly to the additions of this second embodiment latch
construction, a thickened, annular guard plate generally indicated
at 96 is assembled in the exterior operator 28 telescoping and
substantially totally surrounding the lock cylinder frame 84 and
the keyed lock cylinder 86 between the lock cylinder frame and the
combined cover formed by the rosette cover 76 and the lock cylinder
cover 82. This exterior operator guard plate 96 which, like the
lock cylinder cover 82, is circular in vertical cross section, as
shown in FIG. 13, and is thickened in the respect that it is many
times the thickness of the combined cover formed by the rosette
cover 76 and the lock cylinder cover 82, and the guard plate 96 may
be formed of steel and may be of hardened steel where shear
resistance and impact resistance dictate. Furthermore, in addition
to the guard plate 96 projecting outwardly substantially the entire
distance of the lock cylinder frame 84 relatively closely
surrounding this lock cylinder frame, this guard plate is of one
piece including the exterior lip 98 inwardly abutting the door
exterior side 34 and the increased thickness portion 100 projecting
inwardly spaced inwardly of the door exterior side.
Still further, it is again pointed out as hereinbefore described
and clearly shown in FIGS. 11, 12 and 13, that the exterior and
interior operators 28 and 30 are retained assembled with the latch
construction and the latch construction is retained assembled in
the door 32 by the threaded studs 78 of the exterior operator lock
cylinder frame 84 being threadably engaged by the securing screws
80 from the interior operator mounting cover 92 so that all of the
rosette plate or cover 76, the lock cylinder cover 82 and the guard
plate 96 are retained in the assembly of the keyed exterior
operator 28 solely through their respective telescoping and
abutments as described. Thus, with the circular cross-sections of
these covers 76 and 82 and the guard plate 96, each of these cover
and guard plate elements is rotatable relative to the lock cylinder
84 which they surround, that is, as clearly shown, except for the
various telescoping and abutments, these covers 76 and 82 and the
guard plate 96 are free to rotate relative to the door 32 and the
lock cylinder frame 84 if a relatively slight rotative force is
applied thereto which overcomes the friction of abutment of these
elements in the overall exterior operator assembly.
As hereinbefore discussed, the principle means of attempted
violation of latch constructions of the type herein involved is
either by attempted shearing across the exterior operator 28 at the
plane of the door exterior side 34, that is, along the door
exterior side 34 inwardly of the abutment of the rosette cover 76
and across the lock cylinder frame 84, or by impact blows against
the lock cylinder cover 82 and the lock cylinder frame 84, in
either case to remove the exterior operator 28 from the remainder
of the latch construction. Thus, as long as the guard plate 96
remains in place as described, the plane of the door exterior side
34 is securely guarded by the guard plate and particularly the
inwardly projecting increased thickness portion 100, so that
shearing can not take place at this point and the lock cylinder
frame 84 will remain intact. Furthermore, with the outward
projection of the guard plate 96 co-extensive with the lock
cylinder frame 84, extreme rigidity and impact resistance is added
to the lock cylinder frame and it is impossible to violate the
latch construction by impact blows against this outer latch
construction portion.
As hereinbefore indicated, for this shearing protection and impact
protection of the latch construction by the guard plate 96, it is
important that the same remains in place and that there is no
loosening of the exterior operator 28 which could provide access
along the plane of the door exterior side 34 inwardly of the guard
plate 96. To further guard against this loosening of the exterior
operator 28, which could only be caused by an inward deformation of
the interior operator 30 in view of the lock cylinder frame studs
78 and the interior operator securing screws 80, a thickened,
annular guard plate generally indicated at 102 is positioned in the
interior operator 30 within the cover formed by the rosette plate
or cover 76 and the mounting plate or cover 92. The interior
operator guard plate 102 at peripheral portions thereof inwardly
abuts the door interior side or face 36 closely outwardly
underlying the rosette cover 76 and terminates at minimum diameter
adjacent the interior operator securing screws 80 outwardly
abutting portions of the mounting cover 92 directly inwardly
underlying the securing screw head portions, thereby providing
complete rigidity to the interior operator 30 and the securing
screws 80 thereof to prevent any possibility of distortion which
could result in the loosening of the exterior operator 28.
Still in addition, and also important in the frustration of
attempted violations of latch constructions of the type herein
involved, is the fact that all of the rosette cover 76, the lock
cylinder cover 82 and the guard plate 96 are rotatable relative to
the lock cylinder frame 84, each being circular in cross-section
and each being unconnected to the lock cylinder frame 84 and door
32 other than by their respective telescoping and abutments. Not
only does the fact that these outer covers 76 and 82 and the
underlying guard plate 96 are rotatable as described aid in
frustrating shearing and impact attempts through the fact that
forces applied thereagainst tend to rotate the same rather than
properly transfer the forces as intended, but such rotation of the
these elements likewise frustrates attempts to apply twisting
violation forces and sawing violation forces. For instance, if a
twisting force is applied to the lock cylinder cover 82, this lock
cylinder cover will merely rotate with the twisting force and not
effect the underlying guard plate 96 or lock cylinder frame 84, and
if the lock cylinder cover 82 is gripped tightly enough to crush or
collapse the same, this cover merely collapses against the strong
guard plate 96 with the guard plate rotating from the twisting
force and producing the same result. A similar reaction takes place
when there is attempted sawing, since such sawing necessarily
requires that the outer covering elements, primarily the lock
cylinder cover 82 and inwardly thereof the guard plate 96, remain
stationary during such sawing and with these elements relatively
freely rotatable, sawing progress is greatly inhibited, if not
completely frustrated.
According to the principles of the present invention, therefore, a
latch construction is provided having maximum relative simplicity,
yet including the novel bolt dogging arrangement hereinbefore
described, eliminating the greater expense of the conventional
auxiliary dead bolt previously required for such protection in the
prior constructions. Also according to the present invention, the
novel spring 48 constantly resiliently downwardly engaging the
driving levers 44 assures that proper operation of the latch
construction will always take place and particularly augments the
foregoing dead bolt arrangement to assure an even greater security
thereof. Still further according to the present invention, the
latch construction includes single position engageable driving
member 58 and driving shaft 74 which can only be assembled in a
proper relationship so as to eliminate the problems with assembly
encountered with the prior constructions as hereinbefore discussed.
Also, anti-violation guard plates 96 and 102 strengthen the
exterior and interior operators 28 and 30 to prevent the shearing
and impact forms of attempted violations of this or similar forms
of latch constructions.
* * * * *