[0001] During the processing operations for hide tanning, the fleshing of the hide is effected
whilst the same is still fresh after the flaying or after an initial lime pit processing,
so that the hide is in very damp conditions, containing compact matter and clots of
flesh or fat on the inside. The fleshing of the hide consists in removing or cutting
by means of rotating blades said clots or projections and this is done by passing
the hide under tension in front of the series of blades, knives or the like generally
connected to a rotating roller.
[0002] For this operation it is necessary to insert the hide between the cylinder with blades
and the opposing roller on which the hide rests. Said operation is generally done
manually by moving, by means of a rotation of the respective supporting arms, the
said opposing roller away from the cylinder with blades in order to allow the operator
to insert the hide.
[0003] Since the cylinder with blades is kept in a rotatory motion during this operation
in said machines, which present a wide inserting port for the hide, the problem arises
to realize an efficacious protection for the operator's hands,during said inserting
stage of the hide,from the action of the cylinder with blades, which is rotating.
[0004] It is namely necessary that the cutting area be separated from the accessible area
by means of a barrier or screen, hereinafter called protecting shield, which should
be removed only at the time of closing the opposing roller towards the cylinder with
blades, so pressing the hide to be processed.
[0005] These and other problems are solved by the device according to the invention, which
provides a protecting shield, the position ing of which is synchronized with the closing
and opening movements of the opposing roller which bears the hide to be processed.
[0006] Particularly, the self-positioning protecting shield for the cylinder with blades
in fleshing machines and the like consists of a shield or screen extending lengthwise
according to the working length of the cylinder with blades and having width enough
to cover the accesible area of the cylinder with blades itself. The protecting shield
is supported by one or several arms pivoting about the axis of the cylinder with blades,
at least one of which being connected, by mechanical driving means, with one of the
movable arms supporting the opposing roller.
[0007] The rotation of the arms supporting the opposing roller of such an angle to move
the roller itself away from the cylinder with blades, settling in the opening position,
causes the simultaneous rotation of the arm or arms supporting the protecting shield
of such an angle to settle the shield itself in a sheltering or protecting position
in front of the accesible area of the rotating cylinder with blades.
[0008] The rotation of the arms supporting the opposing roller to approach the opposing
roller itself to the cylinder with blades causes the removal, by said mechanical driving
means, of the protecting shield from the working area in front of the rotating cylinder
with blades.
[0009] In particular, the mechanical driving means can consist of crown gears connected
by chains or of gear pairs reciprocally connected, or of a system of connecting rods,
cranks, levers or the like, so realized as to supply the required velocity ratio between
the rotation of the arms supporting the opposing roller and the rotation of the arm
or arms supporting the protecting shield.
[0010] It is therefore assured the positioning of the protecting shield in front of the
cylinder with blades at the opening of the machine by moving the opposing roller away
from the cylinder with blades, as well as the immediate removal of the shield from
the protecting position on closing the machine to start the work, without any delay
or phase difference in this operation.
[0011] A more detailed description of the features of the device according to the invention
refers to the accompanying drawings in which:
Figure 1 is a schematic lateral view of a fleshing machine equipped with the protecting
shield according to the invention, and
Figure 2 is a sectional view according to line II-II of Figure 1.
[0012] The fleshing machine or the like consists of a frame 1 (cut off in Figure 1), bearing
the cylinder with blades 2. In front of the cylinder with blades 2, the opposing roller
3 is arranged, supported by the arm 4 rotating about the axis 5. The opposing roller
3 is movable and it can be moved away from the cylinder with blades 2 by means of
the connecting rod 6 and of the crank 7 rotating about the axis 8 according to the
arrow F, in order to be settled from the "closed machine" position, shown with a continuous
line in Figure 1, to the "open machine" position, shown with a chain in the same Figure
1 and haying references with the prime '.
[0013] The opposing roller 3 can also be approached to the cylinder with blades 2 by a contrary
action of the connecting rod 6 and of the crank 7 in order to settle the machine from
the "open machine" position to the "closed machine" position.
[0014] The moving away movement is actuated by the operator by known means, non shown, in
order to allow the insertion of the hide to be processed 9 on the opposing roller
3, which is in the open position and shown with 3' in Figure 1.
[0015] The rollers 10 and 11, which can be moved away from the opposing roller 3 at the
opening, co-operate with said opposing roller 3 in the closed position. During the
opening of the opposing roller 3, the cylinder with blades 2 remains in rotation.
It is then necessary to assure the safety of the operator by arranging a movable protecting
shield 12, 12' in the sheltering position (shown with a chain in Figure 1),at the
opening of the machine.
[0016] The movement of the protecting shield 12, supported by the arm 13, consists of a
rotation about the same axis 14 supporting the cylinder with blades 2 and it is obtained,
in the embodiment shown in the accompanying drawings, by means of a crown gear 15,
connected by the chain 16 to the crown gear 17. The crown gear 17 is integral and
coaxial to the crown 18, connected by the chain 19 to the crown gear 20, having the
axis 5 and integral to the arm 4. The gear ratio between the crown 20 and the crown
15 is chosen so that, in correspondence to a rotation of the arm 4 enough to pass
from the hide inserting position of the arm 4', shown with a chain, to the working
position of the arm 4, shown with a continuous line, in which the opposing roller
3 bearing the hide 9 is positioned against the cylinder with blades 2, the protecting
shield 12 can rotate from the protecting position of the shield 12' covering the rotating
cylinder with blades 2 to the rest position in which the protecting shield 12 is situated
far from the cutting area and enclosed in the covering 21, which covering 21 constitutes
an external protection of the cylinder with blades 2. The opening movement of the
opposing roller 3 leads at the same time the protecting shield 12 to settle in the
protecting position, while the closing movement of the opposing roller 3 leads the
protecting shield 12 to settle in a position far from the cutting area, without any
delay or phase difference with respect to the motion of the opposing roller 3.
[0017] The mechanical driving can be effected by means of a chain, if that be the case a
double chain, as shown in Figure 2, according to the dimensioning criteria chosen
for the machine. The driving, however, can of course be effected by means of different
systems, for example by means of gear pairs having an appropriate gear ratio, providing,
if that be the case, for appropriate reversal wheels in order to obtain the desired
direction of rotation for the arm 13 supporting the protecting shield 12 according
to the rotation of the arm 4 supporting the opposing roller 3, or by means of a system
of connecting rods, levers and cranks, appropriately dimensioned, or the like.
[0018] The protecting shield, in the illustrated example, consists of a metallic bent element,
extending on an about 90° arc, but it can be otherwise shaped, in machines having
a different configuration, with the corresponding change of the velocity ratio between
the movement of rotation of the arm 4 supporting the opposing roller 3 and the movement
of rotation of the arm 13 supporting the protecting shield 12.
[0019] It is to be noticed the possible application of the invention to machines different
from fleshing machines for the processing of the hides, to which reference has been
made, which machines may present similar problems of protection of the working area
when they are open.
1. A self-positioning protecting device for the rotating cylinder with blades in machines
for hide processing, in particular in fleshing machines, trimming machines, holding
machines or the like, characterised in that it consists of a protecting shield or
screen extending lengthwise according to the working length of the cylinder with blades
and having width enough to cover the accessible area of the cylinder with blades itself,
the protecting shield being supported by one or several arms rotating about the axis
of said cylinder with blades, at least one of which arms is connected, by mechanical
driving means, with one of the movable arms supporting the opposing roller keeping
the hide against the cylinder with blades, so that the rotation of the arms supporting
the opposing roller of such an angle to move the opposing roller itself away from
the cylinder with blades (opening movement) causes the simultaneous rotation of the
arm or arms supporting the protecting shield of such an angle to settle the protecting
shield itself in a protecting position in front of the accessible area of the cylinder
with blades, while the rotation in the opposite direction of the arms supporting the
opposing roller simulatenously moves the protecting shield away from the working area
of the rotating cylinder with blades.
2. A device according to claim 1, characterised in that the mechanical driving means
consist of crown gears connected by chains, which realize the required gear ratio
between the rotation of the arms supporting the opposing roller and the rotation of
the arm or arms supporting the protecting shield.
3. A device according to claim 1, characterised in that the mechanical driving means
consist of gear pairs reciprocally connected such as to have the required gear ratio
between the rotation of the arms supporting the opposing roller and the rotation of
the arm or arms supporting the protecting shield.
4. A device according to claim 1, characterised in that the mechanical driving means
consist of a system of connecting rods, cranks and levers such as to realize the required
velocity ratio between the rotation of the arms supporting the opposing roller and
the rotation of the arm or arms supporting the protecting shield.
5. A protecting device for the cylinder with blades in fleshing machines and the like
for a tannery, substantially as described and illustrated for the specified purposes.