BACKGROUND OF THE INVENTION
[0001] The present invention relates to a high safety lock for overhead doors, gates and
the like.
[0002] Prior locks for overhead or swinging doors, gates or the like, are made in several
different types depending on the application type and/or on the type of gate or door
to be provided with said locks.
[0003] Thus, it is possible to generally classify these prior locks into two classes: locks
provided with automatic means for automatically recovering the lock bolts to the closed
lock position, and locks provided with manual driving means for performing the two
opening and closing operations of the locks.
[0004] Both the above mentioned lock types are provided with driving means, usually controlled
from outside by a lock key and with a manually operated pin in the inside of the lock,
which pin will enable or prevent the operation of the handle by means of which the
lock is opened or closed.
[0005] In these prior locks, the lock handle is latched, in the closure condition of the
lock, so that said handle can not turn, being engaged by a tooth element or by a mechanical
gear assembly thereon the handle, on the contrary, operates, as it is disengaged,
by means of the key or of the pawl element, which can be accessed from the inside
side of the door.
[0006] Since the handle is constantly engaged, even in the closure condition, with the mechanical
system connecting the handle to the lock bolt, it is possible to attempt a tampering
of the latter by applying a comparatively great force on the handle, so as to compel
the latter to turn: this operation, anyhow, will damage the lock assembly, and can
cause the door to be opened in a comparatively easy manner.
SUMMARY OF THE INVENTION
[0007] Accordingly, the aim of the present invention is to overcome the above mentioned
problem, by providing a high safety lock, which can not be tampered even if, with
the lock in its closing condition, the handle is subjected to a comparatively effort.
[0008] Within the scope of the above mentioned aim, a main object of the present invention
is to provide such a lock which, while having a very simple construction, is very
safe in operation and can be provided either with a single or with a plurality of
lock bolts, depending on requirements, and which can be made at a very competitive
cost, much smaller than that of prior commercially available locks.
[0009] According to one aspect of the present invention, the above mentioned aim and objects,
as well as yet other objects, which will become more apparent hereinafter, are achieved
by a high safety lock for overhead doors, gates and the like, comprising a box-like
construction supporting a rotatable handle and at least a sliding bolt, projecting
from said box-like construction, characterized in that said lock comprises means for
connecting the handle to the bolt, as well as means for switching off said connecting
means, which can be controllably driven in order to cause said bolt to slide as the
handle is turned, during the opening or closing operation of the lock, and in order
to cause the handle to idly turn, upon closing of the lock.
BRIEF DESCRIPTION OF THE DRAWINGS
[0010] Further characteristics and advantages of the lock according to the present invention
will become more apparent from the following detailed disclosure of a preferred embodiment
thereof which is illustrated, by way of a merely indicative, but not limitative example,
in the figures of the accompanying drawing, where:
Figure 1 is a front view of the lock, showing only some component elements thereof;
Figure 2 is another front view of the subject lock, in its opening position, with
the bolts thereof in a not engaged condition;
Figure 3 is a further front view of the subject lock, in its closing position, with
the bolts thereof being engaged;
Figure 4 is a cross-sectional view, substantially taken along the section line IV-IV
of Figure 3; and
Figure 5 is a further cross-sectional view of the lock, substantially taken along
the section line V-V of Figure 2.
DESCRIPTION OF THE PREFERRED EMBODIMENT
[0011] With reference to the number references of the above mentioned figures, the lock
according to the present invention, which has been generally indicated by the reference
number 1, comprises a box-like construction 2, rotatably supporting, about an axis
3a, a driving handle 3 and at least a lock bolt 4, projecting from the box-like construction
2.
[0012] In the shown embodiment, are provided four bolts, indicated by the reference numbers
4, 5, 6 and 7, which project from suitable slots, formed through the sidewalls of
the box-like construction 2.
[0013] Between the handle 3 and the bolts are arranged connecting means, and are moreover
provided means for switching off or deactuating said connecting means.
[0014] More specifically, the switching off means can be controllably driven so as to cause
the lock bolt or bolts to slide, as the handle 3 is turned, during the opening or
closing operation of the lock, and so as to cause the handle 3 to idly turn, upon
closing the lock, so as to prevent any tampering attempts to operate the lock bolts
by forcing the handle 3.
[0015] More particularly, the means connecting the handle 3 to the mentioned bolts comprise
a nose element 8, supported by the box-like construction 2, so as to rotate about
its axis, which substantially coincides with the axis 3a of the handle 3.
[0016] The nose element 8 is centrally traversed by a polygonal cross-section hole 9, provided
for receiving the square-cross-section shaft connecting the portion of the handle
arranged outside the door with portion thereof arranged inside the door.
[0017] The connecting means comprise moreover a cam disc 10, which is provided with a central
hole 11 therethrough said nose element 8 is caused to pass.
[0018] More specifically the cam disc 10 is peripherally provided with a plurality of hollows
12, therewithin are engaged pins 13, rigid with said bolts 4, 5, 6 and 7, so that
a rotation of the cam disc 10 will cause the bolts to slide inwardly or outwardly
of the box-like construction 2.
[0019] As shown, the connecting means comprise furthermore a clutch-in device, which is
arranged between the nose element 8 and the cam disc 10, and which can be operated
both for coupling, during the rotary movement, the nose or noix element 8 to the cam
disc 10, and for disengaging, in the rotary movement, these two elements.
[0020] The clutch-in device comprises a sleeve 14 which coaxially extends about the nose
element 8 and is rigid with the latter in the rotary movement about the axis 3a, being
able of sliding in a direction parallel to the mentioned axis 3a.
[0021] The sleeve 14 is provided, at the end portion thereof facing the cam disc 10, with
teeth 15 which can be engaged or disengaged by causing said sleeve 14 to axially translate
with respect to seats or recesses 16 as provided on the cam disc 10.
[0022] The switching-off or disengaging means comprise a slide 17 which is slidably supported,
along a cross direction of the axis 3a, by the mentioned box-like construction 2.
[0023] The slide 17 engages in slots 18, provided on the outer shell of the sleeve 14, and
engages, by a portion 19 thereof, with a slanted surface or plane 20, constituted
by a tab 21 of the mentioned box-like construction 2, said tab being inwardly bent.
[0024] Thus, a displacement of the slide 17 transversely of the axis 3a, will cause, because
of the coupling with the slanted plane 20, a displacement of the slide 17 in a direction
parallel to the axis 3a, so as to disengage the teeth 15 from the seats 16.
[0025] This displacement is counter-biassed by a blade spring 22, arranged between the box-like
construction 2 and the sleeve 14, and operating on the sleeve 14 so as to cause the
teeth 15 to engage with the recesses 16.
[0026] The displacement of the slide 17 transversely of the axis 3a is obtained by a key
device 23, including a cam element 24 which can turn under the action of the key of
the device 23, operating against a shoulder 25 of the slide 17.
[0027] In particular, the slide 17 can also be driven or displaced by manually driving a
pawl 26, which is affixed to the slide 17 and which projects, through a suitable hole
27, from the side of the box-like construction 2 which will face the inside of the
room closed by the door.
[0028] The displacement of the slide 17 in that direction which would cause the clutch-in
device to be disengaged, is resiliently counter-biassed by a spring 28.
[0029] The lock according to the present invention is moreover provided with a further spring
29 which has an end portion thereof affixed inside the box-like construction 2 and
which operates, by the other end portion thereof, on the cam disc 10 so as to provide
a snap type of effect, as the cam disc 10 is brought to the position thereof actuating
the closure of the lock.
[0030] Moreover, the hollows 12 are laterally provided with a recess 30, which will cause
the bolts 4, 5, 6 and 7 to be locked in their closing position, so as to allow said
bolts to be moved in an opposite direction exclusively by rotating the cam disc 10.
[0031] The lock hereinabove disclosed operates as follows.
[0032] In its closing position, which is in particular shown in Figures 3 and 4, the clutch-in
device is deactuated.
[0033] Thus, the nose or noix element 8 and, accordingly, the door handle 3, can turn in
an idle manner, without affecting the cam disc 10.
[0034] Thus, possible tampering attempts on the handle 3, tending to turn the cam disc 10,
will be devoid of any effects.
[0035] In order to open the lock, it is necessary to displace, upwardly in the figures,
the slide 17, by rotating the key inside the key device 23 or by manually operating
the pawl 26.
[0036] This displacement, because of the coupling with the slanted plane 20 and because
of the resilient biassing of the spring 22, will cause the slide 17 to be displaced
in a direction substantially parallel to the axis 3a and, accordingly, the sleeve
14 will be caused to engage, by the teeth 15 thereof, in the recesses 16 of the cam
disc 10, so as to render the cam disc 10 rotatively rigid, about the axis 3a, with
the nose element 8 and, accordingly, with the handle 3.
[0037] Under this condition, a rotary displacement of the handle 3, either inside or outside,
will cause the cam disc 10 to turn and accordingly the bolts to be displaced in the
direction of the box like construction 2, with a consequent opening of the door.
[0038] Thus, in this condition, the door will be enabled for the movement of the bolts,
by operating the handle 3.
[0039] In order to switch-off or disengage this function, i.e. for making the handle and
bolts independent from one another, it will be sufficient to operate on the pin or
pawl 26 or on the key 23, in order to cause the slide 17 to be displaced so as to
disengage the bolts from the handle 3.
[0040] This disabling operation of the lock can be indifferently performed either with the
bolts in their engaged condition or with the bolts in their disengaged condition.
[0041] In this connection, it should be pointed out that, as the key is operated, the enabling
or disenabling conditions will be stable conditions.
[0042] As, on the contrary, the pawl 26 is operated, under the action of the spring 28,
exclusively the disabling condition will be a stable condition.
[0043] From the above disclosure and the observation of the figures of the accompanying
drawings, it should be apparent that the invention fully achieves the intended aim
and objects.
[0044] In particular, the fact is to be pointed out that a lock has been provided in which,
as the lock is in its disabled condition, the driving handle can freely turn without
exerting any effects on the lock bolt.
[0045] Thus, any tampering attempts will be prevented to force the lock to an opened condition
by forcibly turn the handle.
[0046] The invention, as disclosed, is susceptible to several variations and modifications,
all of which will come within the scope of the inventive idea.
[0047] Moreover, all the constructional details can be replaced by other technically equivalent
element.
[0048] In practicing the invention, the used materials, as well as the contingent size and
shapes, can be any, depending on requirements.
1. A high safety lock for overhead doors, gates and the like, comprising a box-like construction
supporting a rotatable handle and at least a sliding bolt, projecting from said box-like
construction, characterized in that said lock comprises means for connecting the handle
to the bolt, as well as means for switching off said connecting means, which can be
controllably driven in order to cause said bolt to slide as the handle is turned,
during the opening or closing operation of the lock, and in order to cause the handle
to idly turn, upon closing of the lock.
2. A lock according to Claim 1, characterized in that said connecting means comprise
a nose element, which is rotatably supported about a rotary axis thereof by said box-like
construction and is axially traversed by a polygonal hole, provided for receiving
the shaft of the handle and a cam disc, rotatably supported about a rotary axis thereof
by said box-like construction and operating on at least a bolt, between said nose
element and cam disc, a clutch-in device being furthermore provided for coupling rotatively
said nose element and cam disc, the switching-off means controllably operating on
said clutch-in device.
3. A lock according to one or more of the preceding claims, characterized in that said
clutch-in device comprises a sleeve, mounted about said nose element and rotatively
rigid therewith about the axis thereof, said sleeve being axially slidable along said
nose element and being provided, at one axial end portion thereof, facing said cam
disc, with engageable or disengageable teeth, under an axial displacement of said
sleeve, with/from recesses provided on said cam disc mounted about said nose element.
4. A lock according to one or more of the preceding claims, characterized in that said
switching off means comprise a slide, which can be displaced in a direction substantially
parallel to the axis of the nose element and engaging with the sleeve of the clutch-in
device, for disengaging it from said cam disc, as counter-biassed by return elastic
means.
5. A lock according to one or more of the preceding claims, characterized in that said
slide is movable transversely of the axis of said nose element, a slanted plane portion
being moreover provided on one of the inner sidewalls of said box-like construction,
engaging with said slide, as it is transversely displaced of the axis of said nose
element, in order to drive said sleeve also in a direction substantially parallel
to the axis of said nose element, in order to switch-on or switch-off said clutch-in
device.
6. A lock according to one or more of the preceding claims, characterized in that said
lock comprises moreover a key device for driving the slide in that direction which
will actuate or switch-on said clutch-in device, against the counter-biassing of said
resilient return means.
7. A lock according to one or more of the preceding claims, characterized in that said
slide is provided, on a side of said box-like body provided for facing the inside
of a room closed by said door, with a pawl for operating said slide in a direction
actuating said clutch-in device.
8. A lock according to one or more of the preceding claims, characterized in that said
cam disc is provided with the plurality of hollows for housing therein pin elements
rigid with said bolts.
9. A lock according to one or more of the preceding claims, characterized in that said
hollows are laterally provided with a recess for locking said bolts in a closing condition
thereof.