[0001] The present invention relates to panic-opening systems for doors of the type comprising
a control bar, which is applied transversely to the door and which can be displaced
by application of a thrust in order to release at least one spring latch, said spring
latch being able to oscillate between an extracted position, in which it engages a
stationary blocking striker, and a retracted position to enable push-opening of the
door. For oscillation of the spring latch between the extracted position and the retracted
position there is provided a slide, which can be translated, from an advanced condition
to a retracted condition as a result of the displacement of said control bar.
[0002] Opening systems of this sort are exposed to the risk of intrusion, which can be perpetrated
by introducing, from outside the door, some kind of tool designed to cause oscillation
of the spring latch towards the retracted position, obviously without any need to
operate the control bar from the inside.
[0003] The purpose of the present invention is to overcome the aforesaid drawback and to
provide a panic-opening system of the type defined above designed to create an effective
obstacle to any attempt at intrusion.
[0004] According to the invention, this purpose is achieved thanks to the fact that the
panic-opening system comprises an anti-intrusion security device designed to block
oscillation of the spring latch towards the retracted position when the slide is set
in the advanced condition.
[0005] According to a preferred embodiment of the invention, the security device includes
a jamming pin, which can be displaced from an operative position to an inoperative
position as a result of the translation of the slide from the advanced position to
the retracted position, and a striker carried by the spring latch and designed to
interact with the jamming pin in the extracted position of the spring latch, where
it engages the stationary striker.
[0006] The said jamming pin is conveniently mounted in a sliding way within a slot opening
of the slide according to two directions, one parallel to and the other transverse
to the direction of translation of the slide. In this case, the striker is made up
of a rocker lever supported in a rotatable way by the spring latch about an axis parallel
to the axis of oscillation of the spring latch and subjected to the action of an elastic
member, which tends to press it in the direction of a first angular position, where
it does not interfere with the jamming pin, the rocker lever assuming a second angular
position, where it is able to interfere with the jamming pin against the action of
the elastic member when the spring latch is set engaging the stationary blocking striker.
[0007] The invention will now be described in detail with reference to the attached drawings,
which are provided purely by way of non-limiting example and in which:
- Figure 1 is a schematic elevation of a door provided with a panic-opening system according
to the invention;
- Figure 2 is vertical cross-sectional view at an enlarged scale according to the line II-II
of Figure 1, in a first condition of the opening system;
- Figure 3 is a front view according to the arrow III of Figure 2;
- Figure 4 is a view similar to the one of Figure 2 in a second condition of the opening system;
and
- Figure 5 is a front view according to the arrow V of Figure 4.
[0008] With initial reference to Figure 1, the number 1 designates a door equipped with
a panic-opening system including, in a way of itself generally known, a control bar
2, which can be operated by application of a thrust (in translation or in rotation)
so as to actuate opening of one or more spring latches. The ensuing description relates,
in particular, to a spring latch 3 set in a position corresponding to the bottom part
of the door 1: it should, however, be noted that the invention can be identically
applied to possible' spring latches located in other positions, for instance, in a
position corresponding to the top part of the door 1.
[0009] The spring latch 3, which is illustrated in greater detail in Figures 2 to 5, usually
co-operates with a stationary blocking striker 4 provided underneath the door 1 on
the inside 5. By means of an actuating tie-rod 6, which can be displaced vertically,
as a result of the movement of the control bar 2, from the lowered position illustrated
in Figures 2 and 3 to the raised position illustrated in Figures 4 and 5, the spring
latch 3 is able to oscillate between an extracted position, in which it engages the
stationary striker 4 (Figures 2 and 3), and a retracted position (Figures 4 and 5),
in which the mechanism for push-opening of the door 1 is released.
[0010] In a generally known way, the spring latch 3 is able to oscillate about a horizontal
transverse pin 7 carried by the side flaps 8 of a supporting element 9, which is in
turn fixed, by means of a base plate 10, to the lower area of the inside edge of the
door 1. A pin spring 11 tends to keep the spring latch 3 in the extracted position
illustrated in Figures 2 and 3, and its rotation towards the retracted position illustrated
in Figures 4 and 5 is obtained as a result of the upward translation of a slide member
12, which is able to slide in a guided way along the supporting element 9 and has
a yoke 13, to which the bottom end of the actuating tie-rod 6 is anchored. The slide
member 12 has on one side, or on each of its sides, a cradle part 14, in which, or
in each of which, a side pin 15 of the spring latch 3 slidably engages. A tension
spring 16 tends to keep the supporting member 9 in the lowered position (represented
in Figures 2 and 3), to which, as has been said, there corresponds the extracted position
of the spring latch 3. When the control bar 2 is actuated by application of a thrust,
bringing about raising of the actuating tie-rod 6, the slide 9 moves upwards against
the action of the spring 16, bringing about, thanks to the interaction between the
side pin or pins 15 and the cradle or cradles 14, rotation of the spring latch 3 about
the axis of the pin 7 towards the raised position (represented in Figures 4 and 5),
thus enabling push-opening of the door 1.
[0011] Provided according to the invention is an anti-intrusion security device for preventing
oscillation of the spring latch 3 towards its retracted position by operating from
outside with some tool so as to cause lifting of the spring latch 3 without the control
bar 2 being actuated. The said security device basically comprises a mobile jamming
pin 17 and a mobile striker 18 carried by the spring latch 3.
[0012] The jamming pin 17 is made with one internal end 19 slidably inserted within a curvilinear
guide slit 20, shaped in the way appearing in Figures 3 and 5, for guiding the supporting
element 9. The internal end 19 of the pin 17 is followed by an annular collar 21 set
between the supporting element 9 and the slide member 12 and by an intermediate portion
22 inserted within a slot 23 of said slide member 12, the said intermediate portion
22 being basically L-shaped, as again may be seen from Figures 3 and 5. The pin 17
terminates with an end bar 30 having a double diameter and projecting outwards above
the spring latch 3.
[0013] The striker 18 consists of a rocker lever supported in a rotatable way by the spring
latch 3 about a substantially central pin 24 parallel to the oscillation pin 7 of
said spring latch 3. The rocker lever 18 is mounted on the pin 24 by means of a slot
25, and its bottom branch 26 is subjected to the action of a thrust spring 27 projecting
from a seat 28 of the latch spring 3. The top branch of the lever 18, designated by
29, is designed to co-operate with the jamming pin 17 according to the procedure described
in detail in what follows.
[0014] In the extracted position of the spring latch 3 (represented in Figures 2 and 3)
corresponding to blocking of the door 1, the jamming pin 17 is set in a lowered operative
position shifted towards the right, as viewed in Figure 3. In this position, the pin
17 is located immediately above the top branch 29 of the oscillating lever 18, the
bottom branch 26 of which pushes against the stationary striker 4. As a result of
this contrast, the oscillating lever 18 is set in an angular position where it is
rotated in a clockwise direction, as viewed in Figure 2, against the action of the
spring 28, with its top branch 29 directed towards the jamming pin 17. In this condition,
any possible attempt at intrusion performed from outside the door 1 in order to cause
lifting of the spring latch 3 would be inevitably prevented by the contrast between
the top of the upper branch 29 of the striker lever 18 and the jamming pin 17. For
the pin 17 to be translated it would have to be displaced also laterally. This, however,
is prevented by the L shape of the slot 23.
[0015] The only possibility for bringing about raising of the spring latch 3 consequently
consists in actuating the control bar 2. In this case, by means of the tie-rod 6,
raising of the slide member 12 is produced against the action of the spring 16. As
a result of this raising, the jamming pin 17 is displaced upwards and, at the same
time, made to translate towards the left along the slot 23 up to the position represented
in Figure 4, as a result of the interaction between its internal end 19 and the guide
slit 20 of the supporting element 9. Following upon this movement, the jamming pin
17 enables free displacement upwards and in a counterclockwise direction of the rocker
lever 18 under the action of the spring 27, whilst the spring latch 3 rotates towards
the retracted position in order to enable push-opening of the door 1 in the way illustrated
in Figure 5.
[0016] Upon subsequent reclosing of the door 1, the spring latch 3 will be able to oscillate
freely from the extracted position to the retracted position in order to overcome
the blocking striker 4, then setting itself once again in the extracted position of
engagement of said striker 4 thanks to the presence of the spring 27, which holds
the oscillating lever 18 in the position in which it is rotated in the counterclockwise
direction represented by a dashed line in Figure 2, where the top branch 29 does not
interfere with the pin 17. After the rocker lever 18 has overcome the stationary striker
4, and the spring latch 3 has returned into its extracted position, the rocker lever
18 will set itself again in the position represented by the solid line in Figure 2.
In this position, the top branch 29 is ready to interact with the jamming pin 17 as
a result of the contrast of its bottom branch 26 against the stationary striker 4.
During this step, the top branch 29 of the rocker lever 18 does not give rise to situations
of interference with the pin 17 thanks to the possibility of the fulcrum 24 translating
along the slot 25 present on the spring latch 3.
[0017] From the foregoing description, it emerges clearly that the panic-opening system
according to the invention enables assurance of a high degree of security against
attempts at fraudulent opening of the door from outside, with a relatively simple
but at the same time particularly effective and functional device.
[0018] Of course, the details of construction and the embodiments may vary widely with respect
to what is described and illustrated herein, without thereby departing from the scope
of the present invention as defined in the ensuing claims.
1. A panic-opening system for doors, comprising a control bar (2), which is applied transversely
to the door (1) and can be displaced by application of a thrust in order to release
at least one spring latch (3), said spring latch (3) being able to oscillate between
an extracted position, in which it engages a stationary blocking striker (4), and
a retracted position to enable push-opening of the door (1), wherein for oscillation
of said spring latch (3) from said extracted position to said retracted position there
is provided a slide (12), which can be translated from an advanced condition to a
retracted condition as a result of the displacement of said control bar (2), said
panic-opening system being characterized in that it comprises an anti-intrusion security device (17, 18) designed for blocking oscillation
of said spring latch (3) towards said retracted position in the advanced condition
of said slide (12).
2. The system according to Claim 1, characterized in that said security device comprises a jamming pin (17), which can be displaced from an
operative position to an inoperative position, as a result of the translation of said
slide (12) from the advanced position to the retracted position, and a striker (18)
carried by said spring latch (3) and designed to interact with said jamming pin (17)
in the extracted position of said spring latch (3), in which it engages said stationary
blocking striker (4).
3. The system according to Claim 2, characterized in that said jamming pin (17) is slidably mounted within a slot opening (23) of said slide
(12) according to two directions, one parallel to and the other transverse to the
direction of translation of said slide (12).
4. The system according to Claim 2, characterized in that said striker is made up of a rocker lever (18) supported in a rotatable way by said
spring latch (3) about an axis (24) parallel to the axis of oscillation (7) of the
spring latch and subjected to the action of an elastic member (27), which tends to
press said rocker lever in the direction of a first angular position, where it does
not interfere with said jamming pin (17), said rocker lever (18) assuming a second
angular position, where it is able to interfere with said jamming pin (17) against
the action of said elastic member (27), when said spring latch (3) is set engaging
said stationary blocking striker (4).