Door hinge

The invention relates to a door hinge comprising two hinge members one affixed to the door and the other to the door frame connected together by two jointing levers and a spring loaded roller engaging one of the levers, the mounting of the roller on the spring member symmetrically with respect to the longitudinal center line of the door hinge member to apply downward pressure on the hinge member of the door during closing when engaged by one of the levers.

The present invention relates to a door hinge with closure pressure device 
formed from at least two hinge members connected by means of joint levers 
and at least one pressure member loaded by the force of a spring arm which 
pressure member rolls or slides on the periphery of at least one joint 
lever. 
The problem of the invention is to improve the door hinge having a closure 
pressure device, which avoids any possible tilting of the pressure member, 
for example a roller due to an asymmetrical force of the pressure spring. 
The present invention has the further problem of further developing a door 
hinge such that the manufacturing costs can be lowered, in particular a 
slot for the guiding of the roller in the base of the stirrup of the 
stationary hinge member. The problem is solved so that the pressure member 
is mounted on a closed spring member of a spring which is mounted 
symmetrically to the longitudinal central axis of the hinge in the 
stationary hinge member. 
With this arrangement a substantial increase of the life with an 
improvement at the same time of the operating safety is obtained. It is 
essential that the pressure member (this may be a roller, a slide or a 
coil of the spring itself) is employed. With this feature it is achieved 
that the pressure member is applied absolutely symmetrical by the force of 
the spring. In this way a closing force is obtained acting exclusively 
perpendicularly to the rolling plane of the joint lever. Any tilting is 
prevented by the symmetrical construction of the spring and by the 
symmetrical bearing of the pressure member; the life and operating 
certainty are substantially increased. 
A further essential feature of the present invention is that the pressure 
member may, for example, be constructed as a roller. The displacement of 
the roller may be effected by suitable limitations imposed on the 
lengthened spring member on the spring. Such limitations on both sides of 
the roller may, for example, be produced by widening the closed spring 
member at these places in order to avoid the roller being capable of being 
removed. 
The certainty of movement of the roller may however be effected by a slot 
in the base of the stirrup of the stationary hinge member through which 
the periphery of the roller partially projects. 
Furthermore the closed spring member of the spring on which the pressure 
member is fixed may also be so formed that the spring coils themselves 
serve for the positioning of the pressure member. 
Finally the pressure members may also be a slide block, a roller which is 
placed on the closed spring member or be formed by the closed spring 
member itself.

In FIG. 1 is shown part of a door 20 movably connected to a stationary 
frame 25 through a door hinge having a top 21. The door hinge thus 
consists of the hinge top 21 inserted in the door and a stationary door 
frame hinge 26 which is fixed by means of a fixing screw 23 on a base 
plate 22 so that the base plate 22 is firmly secured on the frame 25 by 
fixing screws (not shown). The stationary frame hinge 26 contains the 
above described closing pressure device 6 which is described more 
precisely by the following description. 
The hinge top 21 is pivotally connected to the stationary frame hinge 26 
through two levers or link members 10 and 15. The link 15 is fixed to a 
bolt 14 on the hinge top 21 and to a bolt 13 on a stirrup 4 of the 
stationary frame hinge 26. 
The base of the stirrup 4 is provided in with a slot 7 through which the 
pressure member, shown in the embodiment of FIG. 1 as a roller 6, projects 
partly for the purpose of lateral guidance. The closing pressure device is 
essentially formed by a coil spring 30 which is mounted on a pin 2 on the 
stirrup 4 and is supported by the legs 27, 28 on the stirrup 4 and by a 
lengthened spring member 31, defining a light portion (see FIG. 2) on 
which the pressure member, in the preceeding embodiment described, a 
roller 6 is mounted. 
The representation of FIG. 1 shows the door hinge in the open position. In 
this position the roller 6 exerts a closing pressure on the hinge top 21 
because of the off-set of the axis 31 in relation to the axis 11 indicated 
by the dead-center line 9. The roller 6 rolls on a part of the periphery 
of the joint lever 10 and is in the closing position just behind the over 
dead centre 9 on the flank 8b of the cam lobe of the joint lever 10. Upon 
opening the hinge top 21 in the direction of rotation 18 the pressure 
member (roller 6) passes over the dead centre 9 and reaches the flank 8a 
of the joint lever 10 lying tangentially of the bolt 11. In this position 
(open position) no closing pressure is produced. FIG. 2 shows the 
essential features of the present invention. The spring 30 is designed 
symmetrically about the longitudinal central axis of the door hinge. The 
free legs 27, 28 are supported on the viccinity of the centre of the 
spring on the base of the strirrup 4 and by the U shaped portion 31 of the 
spring 31. By means of the arrangement of the pressure member on the U 
shaped spring member 31 of the spring 30 gives an absolutely symmetrical 
loading of the pressure member 6. A rocking of the pressure member 6 on 
the flanks 8a, 8b of the joint lever 10 is now prevented. The embodiment 
according to FIG. 2 has the further advantage that the pressure member is 
disposed so as not to be detachable from the spring member 31 of the 
spring 30. 
In FIG. 1 it is shown that the spring 30 is mounted on the pin 2 in the 
stationary hinge frame 26 (more accurately: in the stirrup 4). Another 
means of fixing is drawn in broken lines. The spring 30 may also be 
positioned on the periphery by lugs 16 pressed out of the stirrup 4 the 
pin 2 being then omitted. 
A further essential feature is that the free legs 27, 28 of the spring 30 
are supported on the stationary hinge frame (stirrup 4). In this way, as 
in the known arrangement in which the free legs are supported on the 
movable hinge and overcome the fact that in known arrangements the closing 
force varies during the opening of the door hinge. 
Another embodiment of the present invention provides for the free legs 27, 
28 to be unsupported directly on the base of the stirrup 4 but into 
contact with a threaded bolt (adjusting screw) and the adjusting screw is 
located in a threaded bore in the base of the stirrup 4. By the adjustment 
of the adjusting screw a variation in the closing force within certain 
limits can be made. 
A further embodiment of the pressure member is shown in FIG. 3. Thus it can 
be seen that the roller 6 according to the embodiment., FIGS. 1 and 2 may 
be omitted; as a pressure member the bent spring member or light portion 
31 of the spring 30 acts as a pressure member or can follower. This bent 
spring member 31 may for the reduction of friction also be coated with a 
plastic or have a sliding block which slides over the associated flanks 
8a, 8b of the lever 10. The bending portion of the spring member 31 of the 
spring 30 may thus be shaped according to the constructional requirements. 
A third embodiment of a spring is shown in FIGS. 4, 5 and 6. From the 
representations it can be seen that the closed spring members 41 on which 
the pressure member is mounted extends from the centre of the spring 40 
and the free legs 37, 38 are formed integrally with the springs 40. With 
this arrangement substantially advantages are achieved. First of all the 
pressure member (roller 6) is held so as not to be detachable from the 
closed spring member 41. Secondly the pressure member is centred by the 
side walls of the bent spring 41 so that a slot 7 according to the 
representation in FIG. 1 for centering the roller 6 on the part of the 
lever 10 can be omitted. This slot could also be omitted in the embodiment 
according to FIG. 3. In both cases the manufacturing costs of the door 
hinge according to the invention are reduced comparted with known 
arrangements. 
In the embodiment according to FIGS. 4, 5, and 6 the roller 6 can be 
replaced by a sliding block or be completely omitted; in the latter case 
the front side of the closed spring member 41 exercises the closing 
pressure on the flanks 8a, 8b of the lever 10. In FIG. 5 the side view of 
a relieved spring 40 according to FIG. 4 is shown. The numeral 32 
indicates the angle around which the closed spring member 41 is turned 
during the mounting in order to produce the necessary tension on the lever 
10 for producing the closing force. The numeral 33 indicates the working 
angle by which the pressure member on the closed spring member 41 is moved 
during the overcoming of the over dead centre point 9 from the flank 8b to 
the flank 8a. This arrangement makes it clear that with the springs 30, 40 
according to the invention, because of their symmetrical construction and 
high pretention provide a high closing force. 
Similarly from FIG. 6 there follows the completely symmetrical construction 
of the spring 40. Thus it is essential for the bent closed spring member 
41 is at the bottom in the direction of the flanks 8a, 8b of the joint 
lever 10 so that other parts of the spring 40 do not rub on the inwardly 
rotating joint lever 10.