[0001] The present invention relates to a closure device particularly for closing doors
in vans, containers freezer cars and the like, capable of giving to the doors maximum
stability in closure, regardless of the type and the direction of the stresses to
which said closure is subject during the movement of the vehicle.
[0002] Various mechanisms have long been known and used which are based on the use of clamps
to ensure the closure of the rear or lateral doors of vans and of containers in general.
Usually these mechanisms have one or more rods mounted vertically and rotatably on
the outer face of the door be it a single door or a door with two shutters with the
free sides partially overlapping in closure; at the opposite ends of each rotatable
rod, a fork-like (or eccentric) locking element is provided arranged at 90° with respect
to the longitudinal axis of the rotatable rod and engaging, in the final step of the
closure of the door, with a variously shaped coupler which is mounted rigidly associated
with the lintel of the opening and is variously shaped, for example as an inclined
plane, pins or lugs protruding from said lintel. The prongs of the forks thus engage
the respective coupler while the door is moved proximate to the closure and then "pull",
that is to say force the stable closure of said shutter during the final step of rotation
of the forkbearing rod.
[0003] These known types of clamps for the closure of doors of vans and the like, though
capable of ensuring a stable closure of shutter doors, in practice are unable to effectively
bear the stresses to which the clamps are subject both as a consequence of the load
being carried and due to the movement on the road. In fact, as is known, a clamp of
this type must be able to recover any of the always possible elastic deformations
of the assembly composed of the door-frame or lintel and of the related shutters and
to oppose as much as possible the onset of vertical and rebound stresses which occur
along the vertical axis of the clamps The closure device must also react to the interior
stresses created by the load bearing on the shutters during accelerations of the vehicle
and oppose the torsional stresses generated by pavement deformations.
[0004] In order to partially overcome these disadvantages and shortcommings, hook-like couplers
have already been proposed which provide a rib or protrusion, substantially in the
shape of a truncated cone, at the end opposite to the one which bears the coupling
forks and axially thereto. Once the coupling is effected, the rib accommodates in
a complementarily shaped seat provided in the coupler plate; this prevents the fork
in closure from moving transversely with respect to the rotatable rod and therefore
allows to oppose any stresses occurring transversely with respect to the shutters,
ensuring a stable closure in this direction. These known couplers, however, are not
capable of opposing all the other previously mentioned stresses to which the clamp
is subject during movement and which jeopardize the stability of the clamp itself.
[0005] Therefore, the aim of the present invention is to provide a closure device particularly
for closing doors in vans, containers, freezer cars and the like, capable to eliminate
the disadvantages and shortcomings of known devices, and most of all such as to be
capable, once the coupling has occurred, of recovering any elastic deformation of
the door-frame/shutter assembly and of opposing with maximum effectiveness the various
stresses to which the closure is normally subject during the movement of a vehicle
on the road, as, for example, of a ship during seafaring transportation.
[0006] A further object of the invention is to provide a structurally simple and highly
reliable door closure device, easily operated in closing and in opening, as well as
adapted to be provided even with two or more closure rods for two shutters according
to the loads and to the stability and safety requirements.
[0007] This aim, this object, and others which will become apparent from the following description,
are achieved by a closure device, particularly for closing doors in vans, containers,
freezer cars and the like, of the type having one or more rods rotatably associated
with a door, a hook associated with the ends of said rods, a coupler device rigidly
associated with the frame of the vehicle door-opening, characterized in that it comprises
a substantially T-shaped element having a vertical portion which can be fixed to said
ends of said rotatable rod and having a horizontal part shaped, at one end, as a fork,
with outwardly curved prongs, during the rotation of said rod, said prongs being inserted
within a coupler element comprising a double lug protruding at one end of a plate-like
element fixed to said frame of said door-opening, said horizontal part of said T-shaped
element being longitudinally splined for its entire length so as to create a longitudinal
groove for the containment and retention of an element in the shape of a continuous
rib provided on said plate-like element, at the end of said rib, opposite to said
end bearing said double lug, an abutment being provided for an end of said horizontal
part of the T-shaped element, the size of said prongs of said fork, of said groove
and of said rib protruding from said plate-like element, being such as to cause the
coupling, between said hook and said coupler, to begin when the curved tips of said
prongs act as levers, by resting on said double lug as a consequence of the initial
rotation of said vertical rod, forcing said longitudinal groove to gradually be inserted
in said rib of said coupler element during the further rotation of said fork-bearing
rod, when the coupling is achieved said end of said horizontal part of said T-shaped
element resting stably against said abutment which protrudes from said rib.
[0008] More particularly, both said longitudinal groove, provided in the horizontal portion
of the T-shaped element, and said rib, protruding from said plate-like element, have
a substantially conical cross section to facilitate their coupling and improve their
stability.
[0009] The invention is described hereinafter in greater detail according to a preferred
but not exclusive embodiment, given only by way of non-limitative example, with reference
to the accompanying drawings, wherein:
figure 1 is a schematic front view of the component elements of an ordinary closure
for doors of containers and the like;
figure 2 is a side view of a hook according to the invention, separated from the rotatable
operating rod;
figure 3 is a front view of the hook of figure 2;
figure 4 is a top view of the hook of figure 2 according to the line A-A of figure
2;
figure 5 is a cross section view along the line B-B of figure 2;
figure 6 is a front view of the coupler element for the hook of figure 2;
figure 7 is a top view of the coupler element of figure 6;
figures 8 and 9 are two cross section views respectively taken along the lines VIII-VIII
and IX-IX of Figure 6;
figure 10 is a view of the positions of the hook of figure 2 approaching the coupler
element of figures 6 and 7;
figure 11 is a front view of the completed insertion of the fork of the hook in the
related coupler; and
figure 12 is a middle cross section view of the insertion of figure 11.
[0010] With reference to said figures, and in particular to figure 1, an ordinary clamp
for doors or shutters of vans and the like is composed of at least one rod 1, usually
tubular at least at its extremities, which is mounted vertically and rotatably on
the outer face of a door and, in the case of a two-shutter door, at the region of
overlapping and mating of one shutter with the other; the rod 1 is rotatably supported
by end brackets 2 and by intermediate brackets 3. A rod-like handle 5 is hinged perpendicular
to the rod at a pivot 4 for rotating the shutter. The handle 5, when the shutter has
been closed, is rotatable until it reaches the position 5a illustrated in phantom
lines and is lockable in an adapted seat 6 by means of a lock 7 or the like.
[0011] The hook means intended to insert in couplers rigidly associated with the frame of
the door opening of the van or of the container are rigidly associated with the two
ends 1a of the rod 1, and substantially form the object of the present invention and
will be described in detail hereinafter with reference to figures 2 to 12.
[0012] Thus, according to the present invention, the closure device comprises a hook to
be welded to the ends of the rod 1 and a coupler element to be connected, by welding
or bolting, to the frame (above and below it) of the door opening of the vehicle,
said door opening not being illustrated in the figures.
[0013] The hook is constituted by a substantially T-shaped element, generally indicated
by 8 in figure 2, having a vertical portion 9 which inserts into the ends 1a of the
rotatable tubular rod 1; an intermediate flange 9a provides an abutment against the
end bracket 2. The horizontal part 10 of the T-shaped element constitutes instead
the hooking and insertion element.
[0014] An end of this hooking element 10 is made in the shape of a fork 10c, the prongs
10a-10b whereof are provided at their ends with two teeth, or tips, 11-11a which are
outwardly curved with respect to the door plane (figures 2-3), that is to say located
at the end of a holder 12 (figure 4). The horizontal part 10 of the T-shaped element
is longitudinally splined for its entire length so as to form a continuous groove
13 having a substantially conical cross section; said groove is open at the end 14
opposite to the fork end; the end 14 being curved and connected to a lower inclined
plane 15 for reasons which will become apparent hereinafter.
[0015] As previously mentioned, two identical hooks 8 are inserted in the opposite ends
of the rotatable rod 1, as schematically illustrated in figure 1. Figure 5 illustrates
a cross section of the horizontal part 10 along the line B-B of figure 2.
[0016] The coupler element, adapted to cooperate with the above described hook, comprises
a plate-like element 16 (figures 6 and 7) provided with means for being fixed to the
door-frame of the vehicle, such as, for example, bolts inserted in the holes 17 or
welding.
[0017] An enlarged portion, forming a continuous rib 18 having a substantially conical cross
section, as clearly illustrated in figure 9, is rigidly associated with said plate
16 and its size is such as to mate with the continuous groove 13 provided longitudinally
in the hook 8.
[0018] A double lug transverse element 19 is provided at one end of said rib 18, while a
heel or protruding abutment 20 (figure 7), against which the planar end 15 of the
hook rests once the coupling has occurred, is provided at the other end.
[0019] The closure device operates as follows (figure 10):
by moving the handle of the rotatable rod 1 which bears the two opposite hooks, the
door is turned on its hinges along the radius of rotation R so that the hooks 8 pass
from position 8 to position 8a etc., until the teeth 11-11a of the fork of the hook
make contact with the double lug element 19; at the moment of the first contact 19a
between the teeth and the double lug element, by reversing the direction of rotation
of the rod 1 the hook and the coupler begin to engage since the fork tips, by resting
on the lugs, act as levers, forcing the longitudinal groove of the hook to gradually
accommodate the rib of the plate 16 until, when the coupling has occurred, the end
15 of the hook rests against the heel 20.
[0020] When the shutters are closed, the hook assumes the position illustrated in figures
11 and 12, wherein: a) the fork 10a-10b engaged by the double lug bears the outward
thrusts against the door from inside; b) the hook end rests against the heel 20, thus
any lateral forces components are counteracted and c) the conical coupling between
the groove 13 and the rib 18, by preventing any possible play, eliminates the vertical
rebound stresses, simultaneously reacting to torsional stresses.
[0021] Furthermore the double lug is engaged at the maximum possible distance and thus the
shutter is "pulled" into the door-frame, facilitating the insertion of perimetral
gaskets made of rubber or the like.
[0022] Naturally, in practice the invention as described above is susceptible to structurally
and functionally equivalent modifications and variations, without thereby abandoning
the scope of the protection of the invention.
1. Closure device, particularly for closing doors in vans, containers, freezer cars
and the like, of the type having one or more rods (1) rotatably associated with a
door, a hook (8) associated with the ends (1a) of said rods (1), a coupler device
(16) rigidly associated with the frame of the vehicle door opening, characterized
in that it comprises a substantially T-shaped element (8) having a vertical portion
(9) which can be fixed to said ends (1a) of said rotatable rod (1) and having a horizontal
part (10) shaped, at one end, as a fork (10c), with outwardly curved prongs (10a,
10b), during the rotation of said rod (1), said prongs (10a, 10b) being inserted within
a coupler element comprising a double lug (19) protruding at one end of a plate-like
element (16) fixed to said frame of said door opening, said horizontal part (10) of
said T-shaped element (8) being longitudinally splined for its entire length so as
to create a longitudinal groove (13) for the containment and retention of an element
in the shape of a continuous rib (18) provided on said plate-like element (16), at
the end of said rib (18), opposite to said end bearing said double lug (19), an abutment
(20) being provided for an end of said horizontal part (10) of the T-shaped element
(8), the size of said prongs (10a, 10b) of said fork (10c), of said groove (13) and
of said rib (18) protruding from said plate-like element (16), being such as to cause
the coupling, between said hook (8) and said coupler (16), to begin when the curved
tips (11, 11a) of said prongs (10a, 10b) act as levers, by resting on said double
lug (19) as a consequence of the initial rotation of said vertical rod (1), forcing
said longitudinal groove (13) to gradually be inserted in said rib (18) of said coupler
element during the further rotation of said fork-bearing rod, when the coupling is
achieved said end of said horizontal part (10) of said T-shaped element (8) resting
stably against said abutment (20) which protrudes from said rib (18).
2. Device according to claim 1, characterized in that said longitudinal groove (13),
provided in said horizontal portion (10) of said hook, and said rib (18) protruding
from said plate-like element (16), have a substantially conical cross section in order
to facilitate their coupling and improve its stability.
3. Device according to claim 1, characterized in that said tips (11,11a) of said pronts
(10a,10b) of said fork (10c) have the shape of a tooth or the like, adapted to constitute
the initial resting regions of said prongs (10a,10b) on said double lug (19) rigidly
associated with said rib (18).
4. Device according to claim 1, characterized in that said end of said horizontal
portion (10) of said T-shaped element (8) opposite to said end having said fork (10c)
is provided partially beveled and partly in the shape of an inclined plane, so as
to allow, once the coupling is achieved, the stable resting of said end against said
abutment (20) provided on said rib (18).
5. Device according to one or more of the preceding claims, characterized in that
said plate-like element (16), bearing said double lug (19) coupler said rib (18) is
rigidly associated with said door-frame of the vehicle and provided with holes (17)
for bolts.