Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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MOUNT FOR FORK-LIFT TINE
SPECIFICATION
FIELD OF THE INVENTION
The present invention relates to fork-lift tine. More
particularly this invention concerns a mount for a removable
fork-lift tine.
BACKGROUND OF THE INVENTION
A standard fork lift or load picker as described in US
patent 5,678,659 and DIN 15178 is a self-propelled vehicle having
a vertically displaceable support carrying a fork normally having
a load lifter constituted as two horizontally outwardly project-
ing tines. These tines are slipped under a load, for instance
into the pockets of a pallet on which the load is stacked, and
the support is raised to pick the load up, whereupon the vehicle
can travel to a location where the load is set down or stacked.
Since the fork must normally be designed for the par-
titular load, it is standard as described in German patent docu-
ment 3,301,756 to mount it so it can be removed from the verti-
tally displaceable support of the vehicle. Thus a fork with
three flat tines can be switched with a fork having two round
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tines, or even with another load lifter. To this brackets are
provided with mouths that engage with lift points on the support,
allowing the transmission of considerable vertical force from the
fork to the support. These brackets are welded to the rear face
of the fork or load lifter.
To prevent the fork from shifting on the support
points, it is known for example as described in ISO 2328 to pro-
vide a spring-loaded latch bolt that is vertically slidable in
the bracket to fit in an upwardly open notch in the vehicle-
mounted support. A retaining lever acts on this slidable bolt.
Thus the bracket is formed with a relatively large-diameter hole
accommodating the bolt, this hole being just where the bracket
fits over the holder.
Such a construction constitutes a weak link in the
connection between the fork~and the support. The exact location
where the brackets fit over the support is interrupted by the
bolt hole so that the weld securing the mounting bracket is also
interrupted at this location. The result is substantial weaken-
ing of the exact region where the considerable forces that the
fork must transmit back to the support are concentrated. Fur-
thermore the known construction provides a trap for moisture and
the like, so that the support point is further liable to corrode.
and degrade with time: While above-cited German patent document
3,301,756 attempts a solution to this problem, the construction
is complex and expensive.
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OBJECTS OF THE INVENTION
It is therefore an object of the present invention to
provide an improved mount for a load lifter on a support:
Another object is the provision of such an improved
mount for a fork or the like on a support which overcomes the
above-given disadvantages, that is which is very strong, simple,
and easy to construct.
SUI~iARY OF THE INVENTION
Irk combination with a load lifter and a vertically
displaceable support adapted to carry the lifter, a mount has
according to the invention an upper bracket having a downwardly
open mouth adapted to fit over the support, and a continuous
lower connection extending horizontally a full width of the
bracket and fixing a lower edge of the bracket to the lifter.
Thus with this system the most highly stressed part of
the connection between the bracket and the load lifter; normally
a fork tine, is formed by a continuous weld. Such a weld can be
made to very high standards since it is not interrupted. As a
result the problem of the bracket tearing off the load lifter is
largely ruled out.
According to a further feature of the invention a con-
tinuous upper connection extends horizontally a full width of the
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bracket and fixes an upper edge of the bracket to the lifter.
Furthermore upright side connections extending vertically between
ends of the upper and lower connections and fixing side edges of
the bracket to the lifter. These connections can all be in fact
a continuous rectangular weld seam that can easily be produced by
a robot welder so that it will be perfectly uniform, especially
when according to the invention the back face of the lifter is
planar and flatly engages a Front face o~ the bracket. The fact
that the weld seams or fillets forming the connections are annu-
larly continuous, means moisture cannot get between the bracket
and the load lifter, eliminating a potential corrosion problem.
In accordance with the invention a latch element on the
bracket can engage the lifter for retaining the bracket against
movement relative to the lifter. To this end the support is
formed with one or more notches and the latch element is
displaceable into and out of a latched position engaged in one of
the notches.
The latch element can be so weighted that gravity
causes it to assume the latched position. Alternately a spring
can be provided to urge it into this position: The element can
be pivotal or slidable into and out of the latched position. It
can also include a shaft pivotal about a shaft axis and having a
radially projecting end engageable into and out of the notch on
pivoting of the shaft. In another system the latch element in-
eludes a coupling wheel, a pin eccentrically connected to the
wheel and displaceable in the bracket to rotate the wheel, and a
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latch member eccentrically connected to the wheel and movable
into and out of the notch on rotation of the wheel. In any case
the latch element has a tip fittable complementarily into the
notch. In another arrangement the latch element is a threaded
bolt that can be screwed down into the latched position.
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BRIEF DESCRLPTION OF THE DRAWING
The above and other, objects, features, and advantages
will become more readily apparent from the following description,
it being understood.that any feature described with reference to
one embodiment of the invention can be used where possible. with
any other embodiment and that reference numerals or letters not
specifically mentioned with reference to one figure but identical
to those of another refer to tructure that is functionally if
not structurally identical. In the accompanying drawing:
FIG. 1 is a perspective view of a fork according to the
invention;
FIG. 2 is an enlarged view of the mount of the fork of
FIG. 1;
FIGS. 3 and 4 are back and side views of the mount in
the latched position,~
FIG. 5 is a side view of the mount in the unlatched
position;
FIGS. 6. and 7 are top and bottom views of the mount;
FIG. 8 is a perspective view of the latching element of
the mount; and
FIGS. 9, 10, and 11 are perspective views of alterna-
tive latching elements in accordance with the invention.
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SPECIFIC DESCRIPTION
As seen in FIGS. 1 through 8 a load lifter is formed as
an L-shaped fork 1 having a horizontal leg 2 adapted to carry a
load and a vertical leg 3 adapted to be attached to a vertically
displaceable support sho~ra .at 20 in FIG. 5 only. This leg 3
carries a downwardly open upper hook bracket 4 and an upwardly
open lower hook bracket 5 so that the fork 1 can be slid horizon-
tally onto the end of the support 20: and will not be able to move
vertically once installed. The entire load carried by the fork 1
is therefore effective outward and dovmward as shown by arrow 6
and upward and inward as sho~m by arrow 6' on the upper bracket
Accordir~g to the invention the bracket 4 is secured to
the back face of the vertical leg 3 at a horizontally continuous
lower weld seam 7, at a horizontally continuous upper weld seam
8, and at a pair of vertical and continuous side seams 9 and 10
that bridge the seams 7 acid 8 and form therewith a rectangular
annularly continuous seam 7, 8, 9, and 10. The continuous nature
of these seams or fillets and the fact that the abutting faces of
the bracket 4 and lifter leg 3 are planar means that the seams 7
- 10 can be made in one Bass by a weldi=ig robot and will be
essentially uniform and perfect, imparting no significant nonuni-
form stresses to the parts 3 and 4 they join. Furthermore they
close the space between the rectangular front face of the hook 4
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and the planar rear face of the leg-3 so that no water can get in
and corrode these parts.
To prevent the lifter or fork 1 from shifting horizon-
tally on the support 20~ it is provided with a latching element
11 pivoted at,a horizontal axis T2 and having a lower end 13
engageable in one of a plurality of upwardly open notches 21
formed in the support 20. A spring such as shown schematically
at 22 (FIG. 4 only) can urge it into the latched position shown
in FIG. 4 and/or the element 11 caa be weighted such that; when
in its normal orientation as shown in the drawing, gravity urges
it into this position. A secondary latch can be provided to hold
it. in the unlatched position of FIG. 5, which secondary latch
needs to be manually released for the element 11 to assume the
latched position.
FIG. 9 shows another latch member 11' that has a pair
of angled slots through which pass pins 15 and 15' seated in the
hook 4 so that a lower end l6' of the member l1' can move into
the notch 21 by gravity. In FIG. 10 a latch member 11" has a
shaft pivotal as indicated by arrow 6" to pivot a lower-end pawl
or finger 16" into the notch 21. FIG. 11 shows an element 11 " '
having a vertically displaceable shaft 18 pivoted eccentrically
on a wheel 19 on which is also pivoted; crank-fashion, another
member 16 " ' movable horizontally as indicated by arrow 6 " ' into
and out of the notch 21. It'is also possible for the element 11
to be secured by a coarse screwthread in the hook 4 so that when
screwed in it projects into the notch 2l.
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