Note: Descriptions are shown in the official language in which they were submitted.
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The present invention relates to a chain conveyor
and more particularly to a conveyor which permits an
accumulation of a certain number of trucks on a section of
the conveyor in accordance with the unloading procedure.
- It is known to employ chain conveyors for
displacing, over a certain horizontal distance, trucks
carrying a load, the return of the empty truck to the point
of departure occuring below the forward travel. It is then
necessary to add to the conveyor proper means for lowering
the trucks at one end and raising the trucks at the other
end, and this requires distinct driving mechanisms provided
with considerable control means which affect the cost price
and the reliability.
An object of the invention is to considerably
simplify these mechanisms by providing a device which
effects both the horizontal transfers and the raising and
lowering of the trucks by a single driving means.
According to the present invention there is
provided a chain conveyor comprising a frame, supporting two
endless parallel driving chains movably mounted on said
frame, trucks drivingly engaged by said two chains, a
driving sprocket wheel and a return sprocket wheel for each
of said two chains, the respective sprocket wheel and the
respective return sprocket wheel being contained in a
corresponding vertical plane, said driving sprockets
engaging said two chains and being so arranged that said two
chains are driven by said driving sprockets in a forward
direction in an upper path and in a return direction in a
lower path below said upper path, said trucks being unloaded
at an end of said upper path and being returned empty in
said lower path, each truck comprising at least one axle,
two sprocket pinions each engaging with a respective one of
said two chains and a friction coupling device mounting said
pinions on said axle, said conveyor further comprising
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curved racks supported at least substantially on a semi-
circle around said sprocket wheels, teeth of said sprocket
pinions being adapted to engage said racks.
According to a preferred embodiment, the curved
ra-cks are formed by fixed chains having the same modulus or
pitch as the driving chains (the word "modulus" refers to
the pitch of the respective chains).
Also, preferably the driving chains are double,
one row of links cooperating with the sprocket pinions of
the trucks and the other row of links cooperating with the
sprocket wheels.
According to another preferred feature, the weight
of the trucks is supported by rollers freely rotatively
mounted on the axles and rolling along runways parallel to
the horizontal portions of the chains.
According to the present invention, there is also
provided a chain conveyor comprising
a frame,
two endless parallel driving chains supported by and
0 movably mounted on said frame,
a driving sprocket wheel and a return sprocket wheel
for each of said two chains,
each of said two chains, the respective sprocket wheel
and the respective return sprocket wheel being contained in
5 a vertical plane,
said driving sprocket wheels engaging said two chains
and being so arranged that said two chains are driven by
said driving sprockets in a forward direction in an upper
path and in a return direction in a lower path below said
0 upper path,
trucks drivingly engaged by said two chai.ns, said
trucks being unloaded at an end of said upper path and being
returned empty in said lower path, each truck including
at least one axle,
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two sprocket pinions each engaging a respective one of
said two chains and
a friction coupling device mounting each of said
pinions on said axle, and,
5curved racks supported at least substantially on a
semi-circle around said sprocket wheels, teeth of said
sprocket pinions being adapted to engage said racks, and
each of said racks being formed by stationary sections of
chain having the same pitch as the driving chains.
10Further features and advantages of the invention
will be apparent from the following description with
reference to the accompanying drawings, which illus~rate an
embodiment given by way of a non-limiting example.
In the drawings:
15Fig. 1 is a side elevational view of an embodiment of
the conveyor according to the invention;
Fig. 2 is a partial plan view of the conveyor of Fig.
1 ;
Fig. 3 is an end elevational view of the conveyor in
20the direction of arrow F of Fig. 1;
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Fig. 4 is an ~arged cross-section view along line rv-rv of Fig.l.
Fig. 5 is a side elev~tional Yiew of one of the ends
of the conveyor.
The conveyor shown in the drawings comprises a frame
1 provided with legs lc bearing on the ground. A motor 2
drives, through a transmission 3, a transverse~shaft 4 on
which are keyed two driving sprocket wheels 5 located at
one end of the frame 1. Extending around each of these
wheels 5 is a double chain 6 consisting of two rows (6a,6b)
of links which engage, at the other end of the frame 1, a
return sprocket wheel 7. The engagement is achieved by
the row 6b of links adjacent to the interior of the frame
1, which 1s formed by longitudinal girders la, lb (inter-
connected by cross-members 23 and vertical posts 24).
Disposed above and below the frame 1 are two side
members 8a, 8b each having a vertical flange 9 and a hori-
zontal branch 10 fixed to the cross-members 23 by bolts
22. Fixed to the horizontal branch 10 of the upper side
member 8b is a slideway 11 along which the u~per portion
of the corresponding chain 6 slides. Fixed to the horizon-
tal branch 10 of the lower side member 8a is a slideway 12
in which slides the row 6b of links of the chain 6 which
engages with the sprocket wheels 5 and 7.
L-section members 13 are fixed to the flanges 9 and
constitute the runways for rollers 14 freely rotatively
mounted on the axles 15 of trucks 15 adapted to shift the
loads and dis2osed between the flanges 5.
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Mounted on at least one or the axles 15 of each truck
16 are two sprocket pinions 17 which permanently engage
with the r~w 6a of links of the chains 6 located on the
outside. Each sprocket pinlon 17 is connected to the axle
by a driving device which provides a friction coupling
18, known Der se assuring the release of the sprocket pi-
nion 17 relative to the axle 15 beyond a certain torque.
The upper side member 8b and lower side member 8a are
interconnected at each end of the frame 1 by a u-section
member 19 which is bent in a semi-circumference. The
outer branch 20 of the section carries, on its inner side,
a fixed chain 21 of the same modulus as the chains 6 and
constituting a curved rack with which the sprocket pinion
17 carried by the axles 15 engage.
Each fixed chain 21 has a development of at least
substantially a semi-circumference but may optionally be
extended by a rectilinear portion. Thus, in the illustra-
ted embodiment, the chain 21 located adjacent to the driv-
ing sprocket wheel 5 and corresponding to the lowering of
the t~ucks, extends from the point A to the point B which
terminates a lower horizontal rectilinear portion~ while
the chain 21 located at the other end and corresponding to
the raising of the truc~s extends from the point C to the
point ~ which terminates the curved portion in the region
of the upper side members 8b.
The conveyor just described operates in the following
manner :
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In the hori20ntal parts not associated with a fixed
chain portion 21, i.e~ from 3 to A for the upper part and
from B to C for the lower part, the sprocket pinions 17
remain rigid with their axle 15 so long as no obstacle
opposes the travel of the trucks 16. The latter are the-
refore driven by the chain 6 which is shifted by the
sprocket wheel 5 and the motor 2 at the s eed of the chain
6. When a truck 16 encounters the preceding truck or a
movable abutment (not shown), a torque is created between
the sprocket pinions 17 and the axle 15 causes a release
of the d r i v e therebetween and therefore the stoppage
of the associated truck 16, while the chains 6 continue
to rotate. Thus, it is possible to accumulate as desired
the full trucks 16 before the unloading station and the
empty trucks before the raising thereof to the loading
station. As soon as the obstacle has disappeared, the
truck starts to move again.
The movable abutments and their actuating means are
well known per se and therefore not described since they
are not part of the invention.
When the teeth of the sprocket pinions 17 of a truck
16 start to engage, at A, with the fixed chains 21, a tor-
que is created between the sprocket pinion 17 and the
axle 15 causing the release of the drive therebetween. There
is then produced an epicyclic movement of the sprocket pinion
17 achieving a positive driving of the trucks 16 with an
over-turning thereof. This manner of travelling continues
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until the sprocket pinions 17 are disengaged from the
chains 21 at s.
A similar operation occurs at the end of the conveyor
between the points C and D achieving the raising and the
over-turning of the trucks 16 which are again ready to
receive a load.
It can be seen that the described device thus ~ermits
achieving very simply all of the horizontal, raising and
- lowering transfers with a single continuously rotating
driving motor.
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