U.S. patent number 3,691,595 [Application Number 05/120,839] was granted by the patent office on 1972-09-19 for lashing fitting.
This patent grant is currently assigned to AB Backtemans Patenter. Invention is credited to Hans Ulrich Backteman, Richard John Taylor.
United States Patent |
3,691,595 |
Backteman , et al. |
September 19, 1972 |
LASHING FITTING
Abstract
Lashing fittings are characterized in that the rotation of the
twistlock is automatically activated by vertical compression caused
by the weight of a container coming into contact with the housing
of the lashing fitting attached to a container or a loading
platform, said twistlock being rotated by means of a force which is
released exclusively by the said act of the weight of a container
reacting against the housing of the lashing fitting thereby
transmitting to the twistlock a revolving movement towards a
locking position within said corner casting. An indicator is
provided for indicating the tripping of the lashing fitting for
connecting the containers in question to the lashing fitting and
thereby to one another, and, on the other hand, angular
displacement in opposite directions of the arrow tip-like heads of
the twistlocks of one lashing fitting in relation to each other
and, further, a sub-division of the revolving movement of the lock
members over an angular range of 180.degree. into two unequal steps
during turning of the twistlocks to respectively the locked and the
released positions.
Inventors: |
Backteman; Hans Ulrich (Bromma,
SW), Taylor; Richard John (Johanneshov,
SW) |
Assignee: |
AB Backtemans Patenter
(N/A)
|
Family
ID: |
26654270 |
Appl.
No.: |
05/120,839 |
Filed: |
March 4, 1971 |
Foreign Application Priority Data
|
|
|
|
|
Mar 6, 1970 [SW] |
|
|
3051/70 |
Feb 9, 1971 [SW] |
|
|
1608/71 |
|
Current U.S.
Class: |
24/287; 24/590.1;
24/DIG.54; 220/1.5 |
Current CPC
Class: |
F16B
12/36 (20130101); B65D 90/0013 (20130101); Y10T
24/4522 (20150115); Y10S 24/54 (20130101); Y10T
24/28 (20150115) |
Current International
Class: |
B65D
90/00 (20060101); F16B 12/00 (20060101); F16B
12/36 (20060101); B61d 045/00 (); B65j
001/22 () |
Field of
Search: |
;24/81E,221R,221L,221K
;287/2 ;248/119R,119S,361R ;105/366,369,366D ;220/1.5 |
References Cited
[Referenced By]
U.S. Patent Documents
|
|
|
3052941 |
September 1962 |
Abolins et al. |
3437055 |
April 1969 |
Wille et al. |
3545713 |
December 1970 |
Mowatt-Larssen et al. |
|
Primary Examiner: Griffin; Donald A.
Claims
What we claim is:
1. A fitting for disengagably securing a freight container to
another container or to loading platform, said fitting being a
separate unit comprising a housing and, extending therefrom, at
least one twistlock member which in an initial position is
insertable into an elongate aperture in a corner casting of a
container, wherein the turning movement of the twistlock member is
automatically tripped upon assembly of a further container with the
fitting previously attached to a container or loading platform, a
twist-exerting member for turning said twistlock member, said
twist-exerting member being adapted to turn the twistlock member
through an angle of 180.degree., said turning action being
sub-divided into a first securing step and a second disengaging
step, said securing step being automatically tripped upon assembly
of a further container with said fitting by the depression of a
tripping stud projecting through a hole in said housing for
releasing the securing step of the twisting action of said
twist-exerting member thereby to turn said twistlock member into a
locking position within said corner casting.
2. The fitting as claimed in claim 1, wherein the twist-exerting
member comprises a torsional spring which, from its nontensioned
position, may be tensioned to said initial position.
3. A fitting as claimed in claim 1, wherein a locking pin is
fixedly connected to the shaft of the twistlock member and in the
tensioned initial position is retained by said tripping stud, said
locking pin upon actuation of said tripping stud being free to pass
past said tripping stud through a recess provided therein.
4. A fitting as claimed in claim 3, wherein a tripper piece is
provided on said tripping stud and being accessible through a
recess in the housing for manual operation of the tripping stud for
releasing the disengaging stop of the turning movement so as to
turn the twistlock member from the container coupling position,
said pin connection to said torsion spring abutting against said
tripping stud, manual operation of said tripper piece causing said
tripping stud to be shifted to a position in which the pin is free
to pass through said recess in the tripping stud to permit the
twistlock member shaft to turn to a position in which the twistlock
member is aligned with the elongate aperture of the corner casting
and the container is adapted to be disengaged from said
fitting.
5. A fitting according to claim 4, said fitting being a separate
unit comprising a housing from which one twistlock member extends
in either direction for simultaneously coupling the fitting with
two containers placed one upon another with said fitting
interposed, the two lock members being identically shaped and
mutually connected by a common shaft extending through said
housing.
6. A fitting according to claim 1, comprising a single lock member
extending from said housing, the opposite side of the housing being
provided with a locking plate, and a locking stud cooperating with
stationary guides on a loading platform for detachable coupling of
a container to said loading platform.
7. A fitting according to claim 1, wherein the housing comprises
two assembled U-beam sections with shank ends of said sections in
mutual contact and fastened by welding along the lines of contact,
said U-beam sections being reinforced by struts welded both to each
other and to the fastened shanks of the U-beam sections, the
longitudinal axis of said through shaft extending in the same
direction as said reinforcing struts, a handle being provided at
one end of the sides of the housing formed by the web portion of
one of said U-beam sections.
8. A fitting for disengagably securing a freight container to
another container or to a loading platform, said fitting being a
separate unit comprising a housing and, extending therefrom, at
least one twistlock member which in an initial position is
insertable into an elongate aperture in a corner casting of a
container, the turning movement of the twistlock member being
automatically tripped upon assembly of a further container with the
fitting previously attached to a container or loading platform, a
twist-exerting member for turning said twistlock member, said
twist-exerting member being adapted to turn the twistlock member
through an angle of 180.degree., said turning action being
subdivided into a first securing step and a second disengaging
step, said securing step being automatically tripped during
assembly of a further container with said fitting by the depression
of a tripping stud projecting through a hole in said housing for
releasing the securing step of the twisting action of said
twist-exerting member thereby to turn said twistlock member into a
locking position within said corner casting, wherein an indicator
is provided to indicate the tripping of the lock means of the
fitting and the coupling of the respective containers to said
fitting and thereby to each other and/or a loading platform.
9. A fitting according to claim 8, wherein the indicator is an arm
journalled for swinging movement about a pivot and during turning
of the lock member to the coupling position being acted upon by a
cam, and a pin provided on said shaft for shifting to a position
extending from said housing through a recess therein.
10. A fitting according to claim 9, wherein a pressure spring urges
said indicator towards its initial position indicating that the
lock means of the fitting does not perform a coupling action.
11. A fitting for disengagably securing a freight container to
another container or to a loading platform, said fitting being a
separate unit comprising a housing and, extending therefrom, at
least one twistlock member which in an initial position is
insertable into an elongate aperture in a corner casting of a
container, the turning movement of the twistlock member being
automatically tripped upon assembly of a further container with the
fitting previously attached to a container or loading platform, a
twist-exerting member for turning said twistlock member, said
twist-exerting member being adapted to turn the twistlock member an
angle of 180.degree., said turning action being sub-divided into a
first securing step and a second disengaging step, said securing
step being automatically tripped during assembly of a further
container with said fitting by the depression of a tripping stud
projecting through a hole in said housing for releasing the
securing step of the twisting action of said twist-exerting member
thereby to turn said twistlock member into a locking position
within said corner casting, wherein the lock members extending in
opposite directions from said housing being mutually angularly
displaced on said common shaft.
12. A fitting according to claim 11, wherein the relative angular
displacement of said lock members is in the range of between
10.degree. and 170.degree..
13. A fitting according to claim 11, wherein the lock members of
the fitting in the tensioned starting position are tensioned for
turning 180.degree. in two unequal steps determined in dependence
upon the actual angular displacement between the lock members.
14. A fitting according to claim 13, wherein when the angular
displacement between the lock members is 30.degree. the first
turning step of the lock members to the coupling position comprises
about 105.degree. and the second turning step of the lock members
to the container disengaging position comprises about 75.degree..
Description
The invention broadly refers to a device for securing a freight
container to a loading platform and/or to another container within
a stack of a multiplicity of such freight containers. In the
following description, the device is referred to as a lashing
fitting and the practice of assembling containers together into a
stack or block is referred to as lashing. Most specifically the
invention refers to a new type of lashing fitting in the form of a
self-contained removable unit adapted to be attached to corner
castings in containers and/or to load decks to cause a container to
become interconnected with another container or to a loading deck
by engagement with the lashing fitting.
Prior art lashing equipment for lashing containers comprise wires,
chains or the like binding together the various containers to form
coherent structures or stacks upon a loading platform such as the
deck of a ship. This prior art procedure has been time consuming
and hazardous due to the fact that the stevedores had to climb up
and down the container stack in order to place or remove the many
various lashing fittings. The prior art also comprises a variety of
lashing fittings which depending on the place of use, such as
between the deck and the lowermost container, between pairs of
stacked containers or on top of the containers, have been of many
different types. Accordingly, loading time has been extended due to
the time consuming and troublesome lashing of the containers and
the necessity to select suitable lashing fittings for use in the
various positions. As port time is an important cost factor,
loading and unloading must be performed with the least possible
delay and for this reason containers of standard type (ISO
standard) have been adopted to an increasing extent, such standard
containers being available in several sizes but having identical
corner castings or corner fittings with mutually corresponding
apertures. Frequently, the loading decks are provided with
apertures corresponding to the apertures of the corner boxes.
However, prior art types of lashing devices do not permit
containers of different height to be accommodated in the same block
because the lateral lashing fittings require a disposition of
containers of identical height adjacent each other. All these
conditions as well as the above mentioned risk of accidents in
connection with manual lashing operations have contributed towards
creating in this field of transport a need for the automatic or
semi-automatic lashing of containers, preferably a means to permit
automatic lashing of containers irrespective of height and lateral
interrelation between stacks within the same block.
All the above mentioned drawbacks of prior art devices and
procedures for lashing containers mutually and in relation to
loading decks can be substantially eliminated in accordance with
the present invention which also complies with the above mentioned
need for arrangements for automatic lashing of containers
irrespective of height, this favorable result being obtained, in
accordance with the invention, in a lashing fitting for releasable
lashing of freight containers mutually and/or in relation to a
loading platform, such lashing fitting being a separate unit
comprising a housing and, extending therefrom, at least one
rotatable lock member, hereinafter called a twistlock, which in an
initial position can be introduced into the elongate aperture of a
corner casting of a container. According to the invention these
lashing fittings are characterized in that the rotation of the
twistlock is automatically activated by vertical compression caused
by the weight of a container coming into contact with the housing
of the lashing fitting attached to a container or a loading
platform, said twistlock being rotated by means of a force which is
released exclusively by the said act of the weight of a container
reacting against the housing of the lashing fitting thereby
transmitting to the twistlock a revolving movement towards a
locking position within said corner casting.
The usefulness of the basic lashing fitting is further enhanced by
certain modifications comprising, on the one hand, the provision of
an indicator for indicating the tripping of the lashing fitting for
connecting the containers in question to the lashing fitting and
thereby to one another, and, on the other hand, angular
displacement in opposite directions of the arrow tip-like heads of
the twistlocks of one lashing fitting in relation to each other
and, further, a subdivision of the revolving movement of the lock
members over an angular range of 180.degree. into two unequal steps
during turning of the twistlocks to respectively the locked and the
released positions.
By way of example some embodiments of the invention will be
described in detail in the following description by reference to
the attached drawings in which mutually corresponding parts have
the same reference designations and in which
FIG. 1 is a perspective view showing several containers during
loading or unloading of one container C,
FIG. 2 is a vertical sectional view of a lashing fitting according
to the invention,
FIG. 3 is a horizontal sectional view of the lashing fitting along
line III--III in FIG. 2,
FIG. 4 is a vertical sectional view of a lashing fitting as being
inserted into two opposed corner castings of two superimposed
containers,
FIG. 5 is a vertical section of a part of the lashing fitting
provided with a protruding bottom plate for attachment in relation
to guide rails on a ship deck or similar platform,
FIG. 6 is a side view of another embodiment of the lashing fitting
according to the invention provided with disengaging means, portion
of the lower part of the housing being broken away to uncover
certain inner structural parts,
FIG. 7 illustrates the lashing fitting shown in FIG. 6 turned
90.degree. from the position shown in FIG. 6,
FIG. 8 is a sectional view along line VIII--VIII in FIG. 7 of the
device illustrated in FIGS. 6 and 7,
FIG. 9 is a view similar to FIG. 6 illustrating another embodiment
of the lashing fitting according to the invention, and
FIG. 10 is a view similar to FIG. 7 of the modified embodiment
according to FIG. 9.
Referring to FIG. 1 there is shown a freight container C being
lowered onto a stack of similar containers. All the containers are
provided with corner castings 11, 12. As appears from FIG. 1
lashing fittings 1 according to the invention are attached to the
upper container C to enable this container to be coupled to the
lowermost forward container within the stack by simply lowering the
upper container C onto the underlying container. As appears from
FIG. 1 containers of varying length may be placed adjacent to each
other, it also being obvious that containers of different height
can be stacked together whereby the need inherent in prior art
systems for a time-consuming assembly of mutually corresponding
containers is eliminated.
Referring to FIGS. 2 and 3 there is shown in detail how the lashing
fitting according to the invention is constructed. A housing is
formed by assembling U-beam sections 1a and 1b with the shank ends
in mutual contact and united by welding along the lines of contact.
Reinforcing struts are welded both to the united shanks of the
U-beam sections and to each other as shown at 1c. A handle 19 is
provided at one side of the box-like housing so formed. A central
shaft 3 extends through said housing 1, both ends of said shaft
being shaped as arrow-tips forming heads 2, 13 on either side of
housing 1. For reasons explained further down either or both of
said heads 2, 13 is provided with a through bore 20. A pin 5 or
similar part extends from shaft 3 within housing 1 to anchor one
end of a torsion spring 4 to shaft 3. The opposite end of torsion
spring 4 is attached to housing 1, for example, as shown in FIGS. 2
and 3 at said reinforcing struts extending between the shank
portions of the U-beam sections. A locking pin 6 is also rigidly
mounted on shaft 3 to restrict in a way as described further down
the revolving movement of shaft 3. Between the surface of either
head 2, 13 facing housing 1 and the housing itself there are
provided guides or filling pieces 18, said guides being firmly
attached to housing 1 and enclosing shaft 3. A tripping stud 7
extends from the interior of housing 1 through one of the housing
walls adjacent shaft 3. A tripper piece 15 is mounted onto the
shaft of release stud 7 inside a recess 16 in the wall of housing
1. For reasons explained further down a recess 8 is provided on the
side of the shaft of release stud 7 facing shaft 3. The lashing
fitting is held in position by insertion of guide or filling piece
18 into the elongate aperture of the corresponding corner casting,
said guide or filling piece having a corresponding cross sectional
shape substantially filling said aperture. An abutment piece 17 is
arranged within housing 1 diametrically opposite said tripping stud
7 in relation to shaft 3. Torsion spring 4 is shown to enclose and
extend around shaft 3.
The lashing fitting as illustrated in FIGS. 2 to 4 operates as
follows. Lashing fittings according to the invention are placed
into the four upper corner castings of a container after a tool has
been inserted through bore 20 of the upper arrow tip head 2 to turn
shaft 3 and its heads 2 and 13 a half turn or 180.degree. in a
direction for tensioning spring 4. During the priming of the
lashing fitting, locking pin 6 passes through recess 8 of tripping
stud 7 and against vertical spring tension (not shown) which
presses tripping stud 7 upwards so that after locking pin 6 has
passed through recess 8, the shaft of tripping stud 7 will provide
a stop against locking pin 6 being returned through recess 8. Now
the lashing fitting is conditioned for the subsequent automatic
lashing or coupling operation.
When a container is lowered upon four tensioned lashing fittings of
the type illustrated in FIGS. 2 to 4, the protruding upper arrow
tip head 2 of the lashing device will enter into the lower corner
casting of the container being lowered in a way as illustrated in
FIG. 4. When the container is lowered onto the lashing fitting the
lower face of the corner casting will depress tripping stud 7
whereby the recess 8 of tripping stud 7 will be aligned with
locking pin 6 which previously in the primed state of the fitting
had been retained by a side surface of tripping stud 7, as appears
from FIGS. 2 and 3, but which now is permitted to pass through
recess 8 under the turning action of torsion spring 4. This enables
shaft 3 with its arrow tip heads 2, 13 to rotate through 90.degree.
until pin 5 which is engaged by torsion spring 4 abuts against the
side face of tripping stud 7. In this position the revolving
movement of shaft 3 will thus be stopped and the arrow tip heads 2,
13 will be stopped in a position at a right-angle to the starting
position, these heads thus extending transversely across the inner
surfaces of the corner castings, thus providing a locking action
enabling the lashing fitting according to the invention to couple
or interconnect the two containers.
When the cargo has arrived at the place of destination and the
containers are to be removed they are released from the lashing
fittings and thereby from each other in the following way: The
tripper piece 15 is actuated manually or with the aid of a tool
through recess 16 in the side wall of housing 1 in a downward
direction as seen in FIGS. 2 and 4 whereby pin 5 is permitted under
the pressure of spring 4 to pass through recess 8 in the tripping
stud 7. Now the accumulated turning force of torsion spring 4 will
cause shaft 3 with its arrow tip heads 2, 13 to turn through an
additional range of 90.degree. until locking pin 6 will abut
against abutment piece 17, as will appear from FIG. 3. In this
position the arrow tip-like heads 2, 13 of shaft 3 will once again
be aligned with the elongate aperture 14 in the corner castings 11,
12 of the containers, heads 2, 13 thus having completed a total
revolving movement through half a turn, so that the upper container
may be lifted off from the lashing fittings unrestricted by the
lashing fittings which remain seated in the lower container.
A modified embodiment of the invention is shown in FIG. 5 showing a
lashing fitting adapted to be inserted into stationary guide rails
10 or similar devices on a loading platform such as the deck of a
ship to enable a lowermost container to be lashed on board. For
this reason the lashing fitting is provided with only one lock
member 2 extending from housing 1 whereas the opposite side of the
house is provided with a locking plate 9, locking stud, locking
flange or the like extending from the housing in an outward
direction. Thus, the lashing fitting can be inserted by a lateral
shifting movement into engagement with stationary guide rails 10 on
the loading platform, whereafter the upper arrow tip head 2 of the
shaft 3 is tensioned by a revolving movement extending over half a
turn thus conditioning the lashing fitting to perform the action
described in connection with the first embodiment when a container
is lowered onto the primed lashing fittings.
In FIGS. 6 to 8 there is shown a modified embodiment of the
invention so constructed that lashing fittings may be suspended
from the bottom face of a container by insertion into the downward
facing corner castings thereof. This result is obtained by
angularly displacing the vertical alignment of arrow tip head 13 on
shaft 3 in relation to the filling piece 18 while arrow tip head 2
remains in alignment with filling piece 18. The angular
displacement between arrow tip head 13 and filling piece 18 amounts
to between 10.degree. and 170.degree., a displacement of about
30.degree. being preferred, but this is obviously dependent upon
the size and shape of the aperture. By thus permitting suspension
of the lashing fitting from the bottom surface of a lifted
container as shown in FIG. 1 stevedores need no longer perform the
hazardous work of climbing upon already stacked containers to place
lashing fittings in to the four upper corner castings. If a lashing
fitting according to this embodiment is to be suspended from the
bottom of a container the lashing fitting is up-ended, and upper
lock member 13 of the lashing fitting -- shown in the drawing as
the lower lock member -- is stressed against tension of spring 4 to
a position aligned with the elongate guide 18 thus permitting the
arrow tip head 13 together with the guide 18 to be inserted into
the elongate aperture in the corner casting of the container. With
the arrow tip head inserted into the corner casting torsion spring
4 will turn back the head of lock member 13 to its initial position
in which the lock member is angularly displaced in relation to the
elongate aperture of the corner casting whereby the lashing fitting
will be securely suspended from the lower surface of the container.
In the primed state of the lashing fitting, locking members 2, 13
together with shaft 3 have been rotated against tension of spring 4
through 180.degree. and the return rotation of shaft 3 resulting
from the said tension of spring 4 is prevented only by the abutment
of locking pin 6 against a stopping piece 32 which is affixed to
stud 7. Upon suspending the lashing fitting from a bottom corner
casting of a container, the filling piece 18 will substantially
fill the elongate aperture of corner casting while locking member
13 will be unrestricted within the corner casting to re-adopt its
angular disposition from filling piece 18 and thereby preventing
the lashing fitting from falling free from the corner casting.
Locking member 2, remaining in alignment with filling piece 18 will
thereby be unhindered from entering into its appropriate location,
and upon making contact with the surface of the lashing fitting's
location, release stud 7 will be depressed sufficiently to allow
locking pin 6 to pass by locking stop 32 during rotation of shaft 3
under pressure from spring 4. Rotation of shaft 3 is then stopped
by the coming into contact of pin 5 with locking stop 32 thus
restraining both lock members 2 and 13 in an angular disposition in
relation to filling pieces 18.
The construction of the release mechanism of the lashing fitting as
shown in FIGS. 6, 7 and 8 is such that the stud 7 is a shaft guided
by bushings 28 and 31 and whose enclosed end is seated upon a
compression spring 30. Upon the shaft of stud 7 is mounted a
triggering piece 15, 29, 33 and locking stop 32. Locking stop 32 is
bevelled on one side so that during the tensioning operation of
spring 4 pin 6 acts against the bevelled surface of locking stop 32
which in turn compresses spring 30, thus allowing pin 6 to pass by
locking stop 32. Triggering piece 15, 29, 33 is a bevelled plate
the upper horizontal part 15 of which projects into a hole 16 in
the end wall of the housing and the ends 29, 33 of which extend
upon a lower horizontal plane than that of part 15 towards the open
side of the housing, thus permitting the triggering mechanism to be
activated from the end or from either side of the lashing
fitting.
As appears from the Figures the lock members 2, 13 are both shorter
and narrower than the filling pieces 18 in order to allow tolerance
for slight misalignment, due to where or the introduction of
foreign matter, of the lock members 2, 13 in relation to filling
pieces 18. By this means the grave risk of accident due to
incomplete disengagement of containers from the lashing fittings
will be minimized.
An indicator shaped as a curved arm 21 and mounted in the box
construction of the housing swings about a pivot pin 23 holding arm
21 by means of a locking washer 24. Indicator arm 21 is tensioned
inwards from the housing 1 by means of a spring 25 mounted between
the housing wall and the indicator arm itself. A cam, pin or
similar member 27 is supported by shaft 3 in a position to contact
the indicator arm 21 during rotation of the shaft and to push it
outwardly in a revolving movement about pivot pin 23 to cause the
outer end of indicator arm 21 to extend through an aperture 22 in
the wall of housing 1 and thus visually to indicate the tripping of
the lashing fitting. In the locking condition of lock members 2, 13
pin 27 is thus in abutting contact with indicator arm 21 to hold
said arm in its extended position. Upon additional turning movement
of shaft 3 pin 27 will be disengaged from indicator arm 21 which
thus will be moved back within the housing by the action of spring
25. An abutment piece (not shown) is provided in a position in
housing 1 diametrically opposed to tripping stud 7 in relation to
shaft 3 for the purpose of preventing shaft 3 from being turned
beyond one half turn from the starting position, said abutment
piece corresponding to abutment piece 17 in the embodiment shown in
FIGS. 2 to 5.
The lashing fitting according to this embodiment as shown in FIGS.
6 to 8 is disengaged in a similar way as the lashing fitting
illustrated in FIGS. 2 to 4. The tripping or triggering piece 15,
29 or 33 is actuated either manually or with the aid of a tool
through recess 16 in the end wall of the housing or, as far as
parts 29, 33 are concerned, through the open side of the box-like
housing construction. Pressure in a direction towards lock member
13 upon anyone of parts 15, 29 or 33 will call the shaft of stud 7
to further depress spring 30 thereby permitting pin 5 to pass by
stop 32 during rotation of shaft 3 under pressure from spring 4.
Rotation of shaft 3 will stop when pin 6 makes contact with the
abutment piece 17 as shown in FIG. 3, and as shaft 3 will then have
rotated through 180.degree., locking member 2 will once again be in
alignment with filling piece 18 thus allowing unrestricted removal
of locking member 2 from its location. To remove the lashing
fitting from its suspension under a container shaft 3 is turned
through the angle of relative angular displacement between lock
member 13 and filling piece 18 until lock member 13 is aligned with
its guide 18 and thus also is aligned with the elongate aperture in
the corner casting. This turning movement is suitably performed
manually by inserting a tool into bore 20 of the lower lock member
2.
In the embodiment shown in FIGS. 2 to 4 the total permissible
turning movement of shaft 3 amounting to half a turn is divided
into two equal stages viz. a locking stage and an unlocking stage,
each stage comprising a turn of 90.degree., whereas in the
embodiment illustrated in FIGS. 6 to 8 the turning movement is
divided into two unequal stages depending on the desired angular
displacement between lock member 13 and the filling piece 18. Thus,
it has been found that in connection with an angular displacement
of 30.degree. between locking member 13 and the filling piece 18
the first turning step of the lock members to the locking position
preferably should comprise about 105.degree. whereas the second
turning step of the lock members 2, 13 to the container-disengaging
position should comprise about 75.degree.. However, these two
different degrees of rotation can be arbitrarily chosen during
manufacture of the lashing fitting by shifting the position of pin
5 in a direction respectively towards and away from lock piece 32
of tripping stud 7 said pin, as shown in FIGS. 7 and 10, being
provided in a plane below the plane of locking pin 6.
The modified embodiment of the invention illustrated FIGS. 9 and 10
is functionally similar to the embodiment shown in FIG. 5, the
lashing fitting of FIGS. 9 and 10 being adapted to be attached to
stationary guide rails or similar arrangements on a loading
platform such as the deck of a ship. For this reason the lashing
fitting according to FIGS. 9 and 10 in a way similar to the
construction shown in FIG. 5 is provided with only one lock member
2 extending from one side of housing 1 whereas the opposite side of
the housing is provided with engaging members 9 extending from the
housing, these members being in the form of locking plates, studs,
flanges or the like which may be integral with the lower part of
the housing. Thus, the lashing fitting according to this embodiment
may be inserted by lateral shifting movement into engagement with
stationary guide rails on the deck of a ship whereafter the upper
arrow tip-like lock member 2 on the turning shaft 3 may be loaded
or tensioned as described above by a half-turn revolving movement.
When a container is lowered for placement onto the deck engagement
with the lashing fitting will take place in the way as described
above as soon as the tripping stud 7 is actuated for releasing the
turning movement of lock member 2, the indicator 21 being caused to
extend through aperture 22 in the housing to visually indicate the
tripping of the lashing fitting. Detachment of lock member 2 from
the superimposed container is obtained in the same way as in the
previously described embodiment by activation of tripper or trigger
piece 15, 29 or 33. In the embodiment illustrated in FIGS. 9 and 10
the turning movement of shaft 3 is performed in two equal steps
each comprising 90.degree..
The expert will appreciate that further modifications of the
invention will fall within the scope of the enclosed claims. For
example, it is possible to pre-load the lashing fitting according
to the invention to its initial state in which the shaft 3 is
primed prior to attaching the lashing fitting to a container.
Moreover, lashing fittings of the embodiment illustrated by
reference to FIGS. 6 to 8 may also be placed in the upper corner
castings of a container in order to receive a further container not
withstanding the fact that from a safety point of view suspension
of the lashing fitting from the bottom of a container is
preferable. While the invention has been described by reference to
some preferred embodiments in which the member exerting the turning
action is a torsion spring, it is of course within the scope of the
invention to use other means for performing the required turning
action, such means, for example, being pneumatic means,
electromotors, etc. However, the pure mechanical operating means as
described appears to form the cheapest and safest solution of the
problem.
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