Technical field
[0001] The present invention is applicable in the sector of electric strikes for doors or
closures, and more specifically of strikes provided with monitoring systems for monitoring
the open/closed state of the door and the state of the internal mechanism of the strike.
Prior state of the art
[0002] Monitoring systems allow controlling the state of the different security systems
integrated in an installation, and in the case of electric strikes, manufacturers
have two types of different monitoring systems:
- Monitoring the state of the door: This refers to the positioning of the door. This
system controls whether the door is open or closed by means of the actual movement
of the door leaf, or whether or not the latch of the door is in contact with the strike,
and therefore whether the door is open or closed, without the door leaf having been
moved.
- Monitoring the state of the internal mechanism of the strike: This refers to the positioning
of the internal mechanisms (levers or cams) which allow locking or unlocking the latch
of the strike. This monitoring system allows knowing whether the strike is locked
or unlocked.
[0003] A monitoring system for monitoring the state of the door or the state of the strike
consists generally of two parts:
- Sensors in the strike.
- External monitoring/indication devices.
[0004] The electric strike alone cannot indicate the open or closed state of the door or
the locked or unlocked state of the internal mechanism of the strike in a manner readily
noticeable for the user. External monitoring/indication devices are required for interpreting
the signal received by the sensors incorporated in the strike.
[0005] The two types of monitoring mentioned above are available in electric strike models
existing on the market. Within this division of monitoring systems, two other types
can furthermore be distinguished based on whether:
- The sensor or the monitoring assembly is arranged on the outside of the box of the
strike.
- The sensor or the monitoring assembly is arranged in the interior, or partially in
the interior, with respect to the box of the strike.
[0006] Monitoring systems arranged on the outside of the box of the strike are made with
a microswitch assembly which is actuated by means of a cam assembled on the front
face of the strike and actuates a mechanical sensor assembled on one of the side faces.
[0007] This sensor is independent of the box of the strike and remains assembled by means
of a plastic box which in turn acts as protection for the sensor and also as a housing
for the connecting strip of the monitoring system.
[0008] This monitoring system allows knowing whether the door, and more specifically whether
the latch of the door, is open or closed. When it receives pressure from the latch
of the door, the cam assembled in the front of the latch of the strike rotates about
a lower shaft, pressing on the sensor which can be formed by a normally open microswitch.
[0009] Said shaft can rotate without coming out as a result of a cavity formed between the
box of the strike, consisting of a base and a cover, and the cam support part. The
sensor causes the signal to reach the upper monitoring system through the strip of
the microswitch.
[0010] The microswitch assembly is formed by a microswitch and a strip, housed in a plastic
box the base of which has lugs which are assembled in holes of the side face of the
strike.
[0011] Unlike the preceding case, monitoring systems arranged in the interior or partially
in the interior allow monitoring the state of the internal mechanism of the strike,
in addition to monitoring the state of the door as mentioned above.
[0012] Since they do not have access to the internal components of the strike, external
monitoring systems do not allow the possibility of knowing the locked or unlocked
state of the internal mechanism of the strike.
[0013] One example of an electric strike with an internal monitoring system is the Series
4 model from Openers & Closers, proprietor of the present invention. This double monitoring
strike furthermore allows the possibility of combining the monitoring of the state
of the door with the monitoring of the levers making up the mechanical locking system.
[0014] The monitoring systems are placed in the rear area with respect to the latch and
below the levers of the mechanical locking system.
[0015] The components intervening in a double monitoring strike, the state of the door,
and the state of the internal mechanism, can also use only one of the systems, by
way of simple monitoring. The operation of the two monitoring systems is explained
below.
[0016] In an installation with an electric strike provided with a monitoring system for
monitoring the state of the door, when the door is closed, the latch of the door presses
on a sliding part which in turn moves the contact of a microswitch indicating the
state of the door; this microswitch can have a normally open (NO) contact or a normally
closed (NC) contact. The signal emitted by this microswitch is received by an upper
monitoring device which converts the signal of the microswitch into a signal that
the user can interpret according to device specifications.
[0017] In the case of an electric strike with a monitoring system for monitoring the state
of the internal mechanism of the strike (locked or unlocked), the sensor interacts
with the very levers of the mechanism, either directly or by means of other complementary
parts intended for such purpose. The sensor can contact any of the levers intervening
in the operation of the locking/unlocking mechanism of the strike.
[0018] Electric strikes in which the short lever of the internal mechanism contacts the
sensor by means of a sliding part guided by the box of the strike are also known.
Again, the sensor can be normally open (NO) or normally closed (NC) and is actuated
by the movement of the aforementioned parts causing the interaction with the coil
or with the return spring of the lever.
[0019] The technical problem being considered relates to the development of an electric
strike with technical features which allow improving the assembly process and reducing
the number of components added when assembling the electric strike.
Description of the invention
[0020] The electric strike of this invention is of the type described in the preamble of
claim 1 and comprising: a box, a swivelling latch swivelling between a retention position
for retaining the latch of a door in a closed position and a release position for
releasing the latch of the door, an internal locking and unlocking mechanism for locking
and unlocking the latch, which can be actuated by the core of a coil, and comprising
a long lever and a short lever which are assembled on respective shafts, a PCB circuit,
two PCB connecting strips, and a monitoring system for monitoring the state of the
internal mechanism of the strike.
[0021] According to the invention, this monitoring system for monitoring the state of the
internal mechanism of the strike comprises an internal microswitch assembly arranged
in the area after the coil, and provided with a sensor connected to a PCB circuit
of the strike; said microswitch assembly is actuated by the core of the coil when
said coil is electrically powered and moves the core towards the short lever of the
strike, so as to unlock the internal mechanism of the strike.
[0022] Once the core has been moved as a result of the action of the coil, said core returns
to the initial position as a result of the action of a spring.
[0023] The sensor can be normally open (NO) or normally closed (NC), according to the desired
function.
[0024] In one embodiment of the invention, this strike has a double monitoring system: the
aforementioned monitoring system for monitoring the state of the internal mechanism
of the strike, and a monitoring system, arranged in the interior or partially in the
interior, for monitoring the state (open or closed) of a door provided with a latch
interacting with the latch of the strike in the closed position of the door.
[0025] This monitoring system for monitoring the state of the door, arranged in the interior
or partially in the interior with respect to the box of the strike, consists of an
actuation lever located in the latch of the strike, and enables the rotation between:
a protruding position in which it is maintained as a result of the action of a spring
when the door is open, and a withdrawn position when the door is closed and the latch
of the door moves it to said withdrawn position.
[0026] In the protruding position, the actuation lever actuates a sensor of the microswitch
assembly of the monitoring system for monitoring the state of the door, indicating
the open position of the door through the PCB circuit and the connecting strip.
[0027] When the door is closed and the actuation lever is in the withdrawn position, said
actuation lever no longer acts on the sensor, providing an indicative signal indicating
that the door is closed.
Brief description of the contents of the drawings
[0028] As a complement to the description provided herein, and for the purpose of helping
to make the features of the invention more readily understandable, the present specification
is accompanied by a set of drawings which, by way of illustration and not limitation,
represent the following:
- Figure 1a shows a front perspective view of an exemplary embodiment of the strike
of the invention, with a monitoring system for monitoring the state of the internal
mechanism, without the cover of the box and the latch of the strike.
- Figure 1b shows a view similar to Figure 1a, in which the levers of the internal mechanism
have been eliminated, and the monitoring system for monitoring the internal mechanism
which can be actuated by the core of the coil can be seen.
- Figure 2 shows a view similar to Figure 1b, with the monitoring system for monitoring
the internal mechanism in an exploded view.
- Figure 3 shows a perspective view of the internal microswitch assembly of the monitoring
system for monitoring the mechanism of the strike.
- Figure 4 shows a rear, perspective, transparency view of the strike of the preceding
figures assembled and non-actuated.
- Figures 5a and 5b correspond to respective elevational and plan transparency views
of Figure 1 with the internal mechanism locked.
- Figure 6 shows a rear perspective view of the strike of the preceding figures with
the internal mechanism actuated by the core of the coil and unlocked.
- Figures 7a and 7b show respective elevational and plan views of the strike with the
internal mechanism in the unlocked position of Figure 6.
- Figures 8 and 9 show respective front perspective views of a variant embodiment of
the strike without the cover and provided with a monitoring system for monitoring
the state of the door.
- Figures 10a and 10b show respective rear, perspective, transparency views of the strike
of Figures 8 and 9, with the actuation lever of the monitoring system for monitoring
the door in a position corresponding to the open position of the door, and acting
on the microswitch assembly of said monitoring system for monitoring the state of
the door.
- Figure 11 shows a front view of the strike with the actuation lever in a position
corresponding to the closed position of the door, moved towards the rear area of the
latch of the strike.
- Figure 12 shows a rear, perspective, transparency view of the strike with the monitoring
system for monitoring the state of the door in the same position as Figure 11, and
with the actuation lever not in contact with the sensor of the microswitch assembly
of the monitoring system for monitoring the state of the door.
Detailed description of embodiments of the invention
[0029] Figures 1 to 7 correspond to an embodiment of the electric strike provided with a
monitoring system for monitoring the state of the internal mechanism of the strike,
which is activated by the core of the coil.
[0030] This strike comprises a series of elements typical of electric strikes, such as:
- a box (1) with a removable cover, - a latch (2), - an internal locking and unlocking
mechanism for locking and unlocking the latch (2) made up of a long lever (4) and
a short lever (7) which are assembled on the respective shafts (5, 6);- a coil (8)
provided with a spring (9), a core (10) and a pin (15); a PCB circuit (13), and two
PCB connecting strips (11).
[0031] When the coil (8) is electrically activated, the core (10) acts on the short lever
(7), moving it to a position for unlocking the long lever (4), and accordingly the
latch (2) of the strike.
[0032] In this first embodiment, the electric strike comprises a monitoring system for monitoring
the state of the internal mechanism of the strike provided with an internal microswitch
assembly (14) connected to the PCB circuit (13) of the strike. Said internal microswitch
assembly (14) is located in the part after the coil (8) and provided with a sensor
which contacts the core (10) of the coil.
[0033] The sensor of the microswitch assembly (14) can be normally open (NO) or normally
closed (NC), according to the desired function.
[0034] In this strike, the core (10) of the coil remains in contact with the sensor of the
microswitch assembly (14) until the coil (8) receives electric current. In that moment,
the core (10) is subjected to a magnetic force induced by the coil (8) and moves towards
the short lever (7). The short lever (7) rotates about its shaft (6) as a result of
the action of the core of the coil (10) and unlocks the internal mechanical system
of the strike, releasing the long lever (4) and allowing the opening of the door when
the latch of the strike (2) rotates as a result of the latch of the door being pulled
in an opening direction. In this situation, the sensor of the microswitch assembly
(14) is in the normally open (NO) state.
[0035] As can be seen in Figures 1a, 4, and 5a, 5b, the internal mechanism of the strike
remains locked. The short lever (7) and the long lever (4) contact one another and
the core (10) of the coil is pressing on the sensor of the microswitch assembly (14)
of the monitoring system and in this situation said sensor is in the normally closed
(NC) position.
[0036] As shown in Figures 6 and 7, when the coil (8) is electrically actuated, the core
(10) moves and acts on the short lever (7) of the internal mechanism of the strike,
causing the movement thereof to a release position for releasing the long lever (4).
At this precise moment, the core (10) of the coil is not in contact with the sensor
of the microswitch assembly (14) of the monitoring system for monitoring the internal
mechanism and said internal mechanism for mechanically locking the latch (2) has been
released, allowing the movement of the latch (2) to an open position of the strike.
[0037] This internal microswitch assembly (14) provides the PCB circuit (13) of the strike
with an indicative signal indicating the locked/unlocked state of the internal mechanism
of the strike.
[0038] In a second embodiment of the invention shown in Figures 8 to 12, the electric strike
further comprises a system, arranged in the interior or partially in the interior,
for monitoring the open/closed state of a door provided with a latch which is retained
by the latch (2) of the strike when the door is in the closed position.
[0039] This monitoring system for monitoring the state of the door comprises a microswitch
assembly (12) connected to the PCB circuit (13) of the strike and provided with a
sensor which can be actuated by an actuation lever (3) located in the latch (2) of
the strike.
[0040] In Figures 8 to 10 corresponding to an open position of the door, the actuation lever
(3) is maintained in a protruding position as a result of the action of a spring (not
depicted) pressing on the sensor of the microswitch assembly (12) indicating the open
state of the door.
[0041] In Figures 11 and 12 corresponding to a closed position of the door, the actuation
lever (3) is moved by the latch of the door to a subsequent position in which it releases
the sensor of the microswitch assembly (12) indicating the closed state of the door.
[0042] The signal produced by the sensor is transmitted to the external monitoring systems
through the PCB circuit (13) and the strip (11) of the strike.
[0043] This strike is easy to assemble and disassemble, and the microswitch assemblies (12,
14) can be welded to the PCB circuit (13) bearing the two PCB connecting strips (11)
which are arranged on opposite sides of the strike or coupled to said PCB circuit
(13) by means of connectors.
[0044] Having sufficiently described the nature of the invention, in addition to a preferred
exemplary embodiment, it is hereby stated for the relevant purposes that the materials,
shape, size and layout of the described elements may be modified, provided that it
does not imply altering the essential features of the invention claimed below.