Adjustable locking door hinge

A locking hinge assembly includes two butt plates or hinge leaves each having a plurality of interlocking knuckles with an axially shiftable hinge pin mating with the knuckles. A locking mechanism carried by the top of the hinge pin includes pressure and sprocket plates, with one plate keyed to the hinge pin and spring devices adjustably compressible to apply varying degrees of biasing force against the movement of one hinge leaf relative the other hinge leaf. This is accomplished due to the juncture of one hinge leaf to the sprocket plate while the keyed pressure plate is fixed relative the other hinge plate.

FIELD OF THE INVENTION 
The present invention relates to improvements in a locking door hinge. More 
particularly the invention relates to a door hinge assembly which allows 
not only for the retention of a door at any desired open position but also 
permits adjustment of the amount of frictional resistance exhibited during 
opening and closing of the door. 
DESCRIPTION OF THE PRIOR ART 
Lockable hinge assemblies are generally well known in the art. U.S. Pat. 
No. 2,427,384 issued to Bushko discloses an adjustable door hinge wherein 
a cam mechanism actuates a locking mechanism to arrest the free motion of 
a door. U.S. Pat. No. 3,629,900 issued to Beerli, Jr. illustrates a 
locking hinge utilizing an axially shiftable hinge pin having a toothed 
portion engageable with a mating portion on one of the hinge leaves to 
secure a door in a desired open position. 
U.S. Pat. No. 3,744,085 issued to Griego discloses a further example of a 
hinge which can be locked in a selected angular position by means of an 
axially shiftable hinge pin. The locking is achieved by a hexagonal plug 
carried by the hinge pin and which cooperates with a mating socket within 
a hinge leaf knuckle. 
None of the above inventions and patents, taken either singly or in 
combination, is seen to suggest the instant invention as claimed herein. 
SUMMARY OF THE INVENTION 
It is often required to keep a door open for a variety of purposes; 
however, in some cases a physical door stop would be inconvenient. It may, 
for instance, obstruct free movement through the door or even cause 
injury. Also it is often required to keep a door partially open, or to 
change the amount of door opening as the situation changes. It would not 
be convenient to reset the door stop each time the requirement to change 
the amount of door opening changes. Additionally, it is advantageous to 
have ready means available to permit alternation of the frictional 
resistance as presented by a hung door and its hinges. In this manner, a 
user would be able to accommodate ambient drafts or an out of plumb 
installation wherein the door would have a tendency to self close or open. 
The present invention provides an easy to use locking hinge assembly which 
is readily adjustable without any tools to permit variation of the biasing 
force as exhibited by a hung door and which allows retention of the door 
in any desired pivotal position. This adjustment is accomplished by 
manipulation of an axially displaceable hinge pin between alternate 
positions. In a released position, the hinge leaves and attached door are 
freely connected. In the locked position, a sprocket mounted upon the 
hinge pin interlocks with catch means fixed relative one of the hinge 
leaves. The degree of biasing action between the two hinge leaves is 
regulated by the adjustment of a nut which controls the clamping force as 
applied by a slip clutch comprising yieldable washers disposed between the 
nut and a base element affixed to one of the hinge leaves. The hinge pin 
is precluded from independent rotary motion by means of a transverse pin 
carried thereby and disposed within an axial slot in the knuckle of one of 
the hinge leaves. Positive limits of travel of the shiftable hinge pin are 
defined by snap-action detent means on the hinge pin and one of the 
knuckles on the same hinge leaf as engaged by the above transverse pin. 
Engagement or disengagement of the biasing/locking device is achieved 
merely by pushing downwardly or upwardly upon a respective end of the 
hinge pin while alteration of the resistive force is easily made by 
tightening or loosening the nut member at the top of the hinge pin, 
usually when the pin is in its lowered, locked position. The exposed, 
working elements of the locking mechanism at the top of the pin are 
usually enshrouded by a protective cap or shield, with only the uppermost 
adjustable nut projecting therethrough. In this manner, the 
locking-unlocking action may be carried out at any time without exposing 
the various elements as contained within the cap. 
Accordingly, one of the objects of the present invention is to provide a 
locking hinge assembly which can be easily actuated to achieve varying 
degrees of frictional resistance between the pivotal motion of the hinge 
leaves. 
Another object of the present invention is to provide an improved lockable 
hinge assembly including an axially shiftable hinge pin nonrotatably fixed 
relative one hinge leaf and supporting a variably adjustable clutch 
mechanism at an end of the pin, together with sprocket and catch elements 
allowing of selective actuation of a biasing force between the two hinge 
leaves. 
A further object of the present invention is to provide an improved 
lockable hinge assembly including a catch element fixed relative one hinge 
leaf and which is engageable with a sprocket freely carried by the hinge 
pin, while a clutch mechanism is variably engageable with the sprocket to 
regulate the frictional resistance between the two hinge leaves. 
With these and other objects in view which will more readily appear as the 
nature of the invention is better understood, the invention consists in 
the novel construction, combination and assembly of parts hereinafter more 
fully described, illustrated and claimed with reference being made to the 
attached drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings, particularly FIG. 1, the locking hinge 
assembly 10 will be seen to be applied to a pair of conventional hinge 
butt plates or hinge leaves 12,14, each having a plurality of intermeshed 
knuckles 16a,16b,16c and, 18a,18b respectively. The leaves are maintained 
in the assembled condition by means of a hinge pin 20 comprising a unitary 
elongated element, the opposite ends of which define a length 
substantially greater than the height of the leaves 12,14. As shown most 
clearly in FIG. 2, the lower end 22 of the pin is provided with an 
enlarged end cap 24 and which may be affixed by any suitable means, such 
as the illustrated screw 26. Movement of the hinge pin 20 is restricted by 
means of a transverse dowel or roll pin 28 carried by the hinge pin and 
having its opposite ends captively located within diametrically opposed 
axially extending slots 30,30 formed in one of the knuckles 18a of one 
hinge leaf 14. 
The above construction will be understood to permit the free axial 
displacement of the hinge pin 20 between the limits of the locked position 
as shown in FIGS. 1 and 3 and the unlocked position of FIGS. 2 and 4. To 
provide means to positively retain the hinge pin in either of these two 
positions, snap means in the form of a spring-urged ball 32 is carried by 
the hinge pin 20, with the ball alternately cooperating with upper and 
lower bores forming detents 34,36 in the knuckle 18b which is part of the 
same hinge leaf 14 as that containing the knuckle 18a engaged by the dowel 
28. With this arrangement, as the hinge pin is axially shifted, it will at 
all times remain nonrotatably fixed relative the hinge leaf 14, regardless 
of its pivotal relationship to the other hinge leaf 12. 
Locking, or regulation of the biasing action between the two hinge leaves, 
is controlled by manipulation of the locking mechanism 38 surrounding the 
upper portion 40 of the hinge pin 20, as located above the top edge 42 of 
the hinge leaves. This mechanism includes a circular base element 44 
having an upper wall 46 and a central bore 48 through which the pin upper 
portion passes. The periphery of the base element 44 will be seen to be 
stepped so as to provide a shelf 50 for reasons which will become apparent 
hereinafter. This base element is secured against independent axial or 
arcuate displacement by being attached to the hinge leaf 12, as by the 
weld 52. With the foregoing in mind, it will be noted that the base 
element 44 is fixed relative the first hinge leaf 12 while the hinge pin 
20 is keyed to the second hinge leaf 14. This relationship will be of 
importance in supporting the operation of the device. 
The various other plurality of components of the locking mechanism all 
comprise circular elements mounted atop the base element 44 and 
surrounding the upstanding pin upper portion 40. A sprocket plate 54, 
bounded by top and bottom flat washers 56,58 revolves about the pin and is 
supported atop the shoulder 60 presented by the enlarged portion of the 
hinge pin. Immediately above the sprocket plate 54, the hinge pin is 
formed with a polygonal cross-section 62, to which is affixed a pressure 
plate 64. The remainder of the pin upper portion is threaded, as at 41 and 
freely accommodates a plurality of compressible washer members such as the 
illustrated Belleville washers 66. An actuating disc 68 having a threaded 
bore reposes above the washers 66 while the endmost element comprises a 
nut member 70. 
When the locking assembly 38 is in the elevated position of FIG. 4, the two 
hinge leaves 12,14 are free to pivot about the common hinge pin 20, 
without any biasing resistance being offered by the locking assembly. On 
the other hand, upon pushing down on the hinge pin 20, the entire locking 
assembly 30 is lowered. Since the sprocket plate 54 is substantially flush 
with the pin shoulder 60, it follows that the sprocket plate will be 
displaced to a position substantially juxtaposed the top wall 46 of the 
base element 44. During this latter movement, an interlocking occurs 
between the sprocket plate 54 and the first hinge leaf 12. This is 
provided by a catch or stud 72 projecting upwardly from the base element 
top wall 46 and which engages between a pair of adjacent teeth 74, 74 on 
the sprocket plate. As shown in FIG. 4, the bottom of these teeth are 
beveled to facilitate the admission of the catch 72 between two adjacent 
teeth as the pin 20 is pushed downwardly. 
When shifted to the lowered or locked position, the base element 44, 
sprocket plate 54 and first hinge leaf 16 become as one, while the hinge 
pin 20, pressure plate 64 and second hinge leaf 14 are all interlocked as 
another body. It thus follows that any frictional resistance brought to 
bear between these two sets of components will in turn, produce a 
resistance between the normal pivoting of the two hinge leaves. Such 
frictional resistance is regulated by the application of a compressive 
force upon the washers 66 and which is transmitted as a downward force 
urging the pressure plate 64 against the sprocket plate 54, the latter of 
which is bearing upon the shoulder 60 of the hinge pin 20. Since the 
pressure plate 64 is keyed relative the hinge pin 20, it will be 
appreciated that any drag imposed upon the pressure plate will be 
transmitted to the second hinge plate 14 by way of the dowel 28 whereby, a 
corresponding frictional resistance between the pivoting of the two hinge 
leaves 12, 14 is created. 
Variation of the biasing force is readily accomplished by advancing or 
retracting the actuating disc and jam nut 70 along the pin threads 41 so 
as to alter the compressive force being applied to the spring washers 66. 
Obviously, alternate numbers and sizes of Belleville springs or washers 
may be employed according to specific requirements and hinge sizes. 
When it is desired to release the locking mechanism 38, one merely pushes 
up upon the lower end cap 24, to position the components as in FIG. 4 
whereupon the sprocket plate 54 is elevated from its engagement with the 
catch 72 and the two leaves 12, 14 assume a natural pivoting about the 
common hinge pin 20. 
To protect the locking components and present a more pleasing appearance, a 
top cap 76 having a central opening 78 snapfits into the position shown in 
FIGS. 1 and 3. This fitting occurs due to a press fit between the cap 
skirt 80 and the base element shelf 50. 
From the foregoing it will be appreciated that an improved locking hinge 
assembly is provided allowing of ready variation of a biasing force 
between two hinge leaves and wherein this force may be selected to merely 
retard the free movement of a hung door or to more positively retain a 
door in a desired position. 
It is to be understood that the present invention is not limited to the 
sole embodiment described above, but encompasses any and all embodiments 
within the scope of the following claims.