Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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TITLE OF THE INVENTION
SHEARING MACHINE
BACKGROUND OF T~E INVENTION
_ield o~ the Invention
The present inven-tion relates generally to a
shearing machlne for cutting or shearing sheet-like
workpieces such as sheet metals. More particularly, the
present invention pertains to a shearing machine which
is provided with two pairs of upper and lower blades in
a manner such that the upper and lower of one pair are
connected to the upper and lower blades, respectively, of
the other pair at right angles to shear right-angled
blanks out of sheet-like workpieces.
Description of the Prior Art
As is well-known, generally shearing machines
for cutting or shearing sheet-like workpieces such as
sheet metals are each provided with an elongated moveable
upper blade carried by a ram member and an elongated
fixed lower blade which is fixedly provided under the
upper blade to cooperate therewith. The ram member
carrying the upper blade is so arranged as to be mechani-
cally or hydraulically moved up and down to bring the
upper blade into and out of engagement with the lower
blade to cut or shear the workpieces. Also, the ram
member is straightly or vertically moved up and down in
what is called a guillotine-type shearing machine, and
it is swung up and down around a pivot means in what
is called a swing-type shearing machine. Generally,
the swing-type shearing machines can be manufactured
and assembled at ~ower costs than the guillotine-type
shearin~ machines. Also, the upper blade is so disposed
as to be inclined or tilted at an angle that is shear
angle to the lower blade so as to decrease the shearing
force required. However, too large shear angle of the
upper blade to the lower blade will cause the workpieces
being sheared to be deformed or twisted.
Heretofore, there have been shearing machines
which are each provided with two pairsof upper and lower
blades in a manner such that the upper and lower blades
of one pair are connected to the upper and lower blades,
respectively, of the other pair at right angles so as to
shear right-angled blanks out of sheet-like workpieces.
Such shearing machines have been variously disclosed in
U.S. Patents: Nos. 3,215,017; ~,964,984; 2,654,428;
3,205,748; 3,616,719; 1,416,800; 1,447,247 and 3,691,887
for example. In such a shearing machine, the upper
blades are mounted at the right angle to each other on
a ram member which is movable up and down in a frame
having a C-shaped throat into which a workpiece to be
sheared is to be fed, ~hile the lower blades are
fixedly mounted at the right angle to each other on a
portion of the frame. Of course, the arrangement is such
that the upper blades are moved up and down by the ram
member into and out of engagement with the lower blades
to cooperate therewith to shear right-angled blanks
out o~ a workpiece which is fed into the throat.
~eretofore, it has been disadvantageous that
the shearing machines each having the two pairs of upper
and lower blades as described above are costly in that
they are constructed in the guillotine-type manner so
that the ram member is straightly or vertically moved
up and down. There may have been some shearing machines
of the swing-type in which the ram member carrying the
two upper blades is swung up and down on a pivot means
as has been disclosed in the U.S. Patent No. 3,691,887
listed above. Indeed, it will be easily thinkable that
the ram member carrying the two upper blades can be
so arranged as to be swung up and down on a plvot means
with one of the two upper blades disposed in parallel
with the pivot means and with the other blade
perpendicular to the pivot means. In this nanner,
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however, it is practically disadvantageous that the shear
angle of the upper blade perpendicular -to the pivot
means will ~e largely changed and become too large with
regard to the mate lower blade since the upper blade
perpendicular to the pivot means is rotated around the
pivot means as the ram mem~er is s~ng therearound.
Of course, if the shear angle of the upper blade to the
lower blade is largely changed and becomes too large
during a shearing operation, the upper and lower
blades cannot made an accurate shearing action with
the result that the workpiece to be sheared will be
deformed and twisted. Thus, it must be that there
has been no swing-type shearing machine that is capable
of making an accurate shearing action to shear right-
angled blanks out of sheet-like workpieces, in spite
of the fact that the swing-type shearing machines can
be manufactured and assembled at lower costs.
Another disadvantage with regard to the
con~entional shearing machines having two pairs of
upper and lower blades has been the fact that a work-
piece larger in width than the horizontal depth or
length of the throat of the machine frame cannot be
sheared. In other words, it has been disadvantageous
in the conventional shearing machines that the maxîmum
width of workpieces capable of being sheared is limited
to the horizontal depth of the throat formed in the
machine frame.
_MMARY OF THE IN~ENTION
It is an object of the present invention to
provide a swing-type shearing machine having two pairs
of upper and lower blades for shearing right-angled
blanks out of sheet-like workpieces in which the
shear angles of the upper blades to the lower blades
can be kept optimum or withinlimits during a shearing
operation.
It is therefore another objec-t of the present
invention to pxovide a swing-type shearing machine
having two pairs of upper and lower blades for shearing
right-angled blanks out of sheet-like wor]cpieces which
is capable of making shearin~ actions without deforming
and twisting workpieces to be sheared.
Accordingly, it is the most important object
of the present inven-tion to provide a swing-type shearing
machine having two pairs of upper and lower blades for
shearing right-angled blanks out of sheet-like workpieces
which can be manufactured and assembled at a lower
cost but is of good performance.
In order to attain these objects, a shearing
machine according to the present invention is so
constructed that the two upper blades are connected
with each other at a right angle on the ram member in a
manner such that their shearing edges are originally
inclined downward from their intersecting point to their
respective free ends. Also, the ram member carrying
the upper blades is pivotally connectPd to the machine
frame by means of a pivot means which is horizontally
disposed higher than the top level of the lower blades.
It is a further object of the present invention
to provide a swing-type or guillotine-type shearing
machine having two pairs of upper and lower blades for
shearing right-angled blanks out of sheet-like workpieces
in which the maximum width of workpieces that can be
sheared is not limited by the machlne frame.
It is therefore an object of the present
invention to provide a swing-type or guillotine-type
shearing machine having two pairs of upper and lower
blades for shearing right-angled blanks out of sheet
like workpieces which is of a larger capacity as compared
with the size of the machine frame.
In order to a-ttain the immediately above
described objects, a shearing machine according to the
present invention is so constructed that one of the two
pairs of upper and lower blades are located outside
of the vertical plane of the outer side o~ -the machine
frame together with related parts.
Other and further objects an~ advantages of
the present invention will be apparent from the following
description and accompanying drawings which, by way of
illustration~ show preferred em~odiment of the present
invention and the principle thereof.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a perspective view showing a
shearing machine embodying the principles of the present
invention.
Fig. 2 is a front elevational view showing
schematically the important portions of the present
invention of the shearing machine shown in Fig. 1.
Fig. 3 is a side eleva~ional view showing
schematically the important portions of the present
invention of the shearing machine shown in Fig. 1.
Fig. 4 is a schematic developmental view in
which members actually disposed at right angles with
each other in the shearing machine shown in Fig. 1 are
shown schematically as put together on the same plane.
Fig. 5 is a schematic plan view showing the
important portions of the present invention o~ the
shearing machine shown in Fig. 1.
DESCRIPTION OF T~LE PREFERRED EMBODIMENTS
Referring now to Fig. 1, there is shown a
snearing machine 1 which embodies the principles of -the
present invention as an example. The shearing machine
1 comprises a pair of C-shaped upright plates 3 and 5
which are formed a-t their midway portions with thxoats
3t and 5t, respectively, and are connected with each
other by an upper front plate 7, a lower front plate 9
and a rear plate 11 shown in Fig. 3 to form a box-like
fxame. Particularly, the upright plates 3 and 5 are
disposed in parallel with each other, and the upper and
lower front plates 7 and 9 are fixed to the upper and
lower portions, respectively, of the forward ends of the
upright plates 3 and 5 at right angles therewith. Also,
the throats 3t and 5t of the upright plates 3 and 5
are horizontally formed on a level with each other in
such a manner as to extend in parallel with each other
and open forwardly about the top of the lower front plate
9.
The shearing machine 1 is provided with a ram
13 carrying an elongated upper front blade 15 and an
elongated upper side blade 17, and it is also provided
with an elongated lower front blade 19 and an elongated
lower side blade 21. The ram 13 is so disposed as to be
moved up and down between the upright plates 3 and 5
behind the front upper plate 7 to move the upper front
and side blades 15 and 17 up and down, as will be
described in great detail hereinafter. The upper front
blade 15 is detachably fixed to the forward bottom end
of the ram 13 in parallel with the upper front plate 7,
and the upper side blade 17 is detachably fixed to the
side of the ram 13 in parallel with the upright plate 5.
More specifically, the upper front and side blades 15
and 17 are fixed to the ram 13 in such a manner to be
integrally connected with each other at a right angle
to work as a single L-shaped blade. On the other hand,
the lower front blade 19 is detachably and horizontally
fixed to the top of the lower front plate 9, and the
lower side blade 21 is detachably and horizontally fixed
to the throat 3t of the upright plate 3 on a level with
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the lower front blade 19. In the same manner as -the
upper front and side blades 15 and 17, the lower front
and side blades 19 and 21 are integrally connected with
each other so as to work as a single L-shaped blade.
Of course, the arrangement is such that the upper
front and side blades 15 and 17 will be brought by the
ram 13 integrally simultaneously into engagement with
the lower front and side blades 19 and 21 t.o cooperate
therewi.th to make a shearing action when the ram 13 is
lowered.
As shown in Figs. 1 and 3, the ram 13 is
pivotally held on a pivot means 23 such as a shaft
held between the upright plates 3 and 5 for the most
important purposes of the present inve.ntion which will
be seen hereinafter as the aescription proceeds. Also,
the pivot means 23 on which the ram 13 is held in disposed
higher than the horizontal plane or level of the top
surfaces of the lower front and side blades 19 and 21
as shown in Fig. 3. Thus, the ram 13 is so arranged
as to be rotated or swung around the pivot means 23
up and down by a drive means (not shown) to move the
upper front and side blades 15 and 17 toward and away
from the lower front and side blades 19 and 21.
As is shown also in Fig. 1, the shearing
machine 1 is provided with a work-table 25 on which
a sheet-like workpiece W to be sheared such as a
sheet metal is placed to he fed into between the upper
front and side blades 15 and 17 and the lower front
and side blades 19 and 21 into the throats 3t and 5t
of the upright plates 3 and 5. The work-table 25 is so
constructed that its top surface is substantially on a
level with the top of the lower front and side blades
19 and 21. In order to feed and position the workpiece
W to be sheared, the work-table 25 is provided with a
first carriage 27 horizontally movable and a second
carriage 29 slidably mounted on the first carriage 27
to carry the workpiece ~. The first carriage is so
arranged as to be horizontally moved ~y a motor 31 on
the work-table 25 toward and away from the lower
front and side blades 19 and ~1, while the second
carriage 29 is so arranged as to be horizontally moved
by a motor (not shown) on the first carriage 27
rightward and leftward. Thus, it will be understood
that the workpiece ~ placed on the work-table 25 and
held by the second carriage 29 can be fed and positioned
anywhere onto the lower front and side blades 19 and 21
by moving the first and second carriages 27 and 29.
In the above described arrangement, the
workpiece W can be sheared when it has been positioned
onto the lower front and side blades 19 and 21 by the
first and second carriages 27 and 29 and the ram 13
is lowered to enable the upper front and side blades
15 and 17 to cooperate with the lower front and side
blades 19 and 21. As is readily understood, the
woxkpiece W can be straightly sheared when it is
positioned on either of the lower front and side blades
19 and 21, and also it can be sheared into a L-shaped
configuration when positioned on both of them. Also,
even if the workpiece W is larger in width than the
length of the upper and lower front blades 15 and 19
which are mostly longer than the side blades 17 and
21, it can be straightly sheared or slit if it is fed
l~ttle by little along the upper and lower front blades
15 and 19 for instance with the ram 13 continuously
stroked.
As best shown in Fig. 4, in which the upper
front and side blades 15 and 17 are schematically
shown as developed or put together on the same plane,
the shearing edges of the upper front and side blades
15 and 17 are so designed as to be inclined at angles
~ and ~, respectively. More specifically, the
shearing edge of the upper front blade 15 is inclined
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at the angle ~ in a manner such that its right-hand
end Q is lower than the intersecting point P at which
the shearing edges of the upper front and side blades
15 and 17 intersect with each other, as shown also in
Figs. 1 and 2 in addition to Fig. ~. Also, as seen
from ~igs. 1, 3 and 4, the shearing edge of the upper
side blade 17 is inclined at the angle ~ in a manner such
that its rear end R is lower than the intersecting
point P of the shearing edges of the upper front and
side blades 15 and 17. It may be understood that the
shearing edges of the front and side blades 15 and 17
are at the angles ~ and ~, respectively, to the hori~ontal
plane when the ram 13 is so positioned that the flat
side of the front upper blade 15 is ver~ically directed
downwardly. Stated other~ise, the shearing edges of
the upper front and side blades 15 and 17 are at the
angles ~ and ~, to a plane to which both of a plane
of the flat side of the upper front blade 15 and a
plane of that of he upper side blade 17 are normal.
Thus, the upper front blade 15 is so arranged as to
ascend at the shear angle ~ from the right-hand end
Q toward the intersecting point P, and the upper side
blade 17 is so designed as to descend at the angle
from the intersecting point P toward the rear end R.
Accordingly, the angle ~ at which the upper side blade
17 is inclined can be regarded as negative assuming
that the shear angle ~ of the upper front blade 15
is positive. As will be seen hereinafter, the angle
~ of the upper side blade 17 is set negative so that
3a the angle at which the upper side blade 17 is inclined
to the lower side blade 21 may be kept within limits
without becoming too large when the upper and lower
side ~lades 17 and 21 are in engagement with each other
to make a shearing action.
In the above described arrangement, the upper
front blade 15 will be kept substantially at the angle
~ to the horizontal plane wherever the ram 13 is
rotated or swung around the pivot means 23. Although
strictly the angle ~ of the upper front blade 15 to
the horizontal plane may be changed as the ram 13 is
rotated or swung around the pivot means 23/ such change
can be functionally neglected since the ram 13 is
swung up and down on the pivot means 23 around a little
angle. Thus, the upper front blade 15 will be brought
into engagement with the lower front blade 19 at the
angle ~ to cut into the workpiece W at the angle ~,
and therefore the angle ~ of the upper front blade
15 can be regarded as what is called shear angle.
On the other hand, the upper side blade 17
could not be kept at the angle ~ to the horizontal
plane when ~oved up and down by the ram 13, since the
ram 13 is rotated or swung aroung the pivot means ~3
to move the upper side blade 17. Although of course
the angle ~ at which the upper side blade 17 is
originally inclined on the ram 13 will be always kept
unchanged, the angle of the shearing edge of the upper
side blade 17 to the horizontal plane will be changed
as the ram 13 is rotated or swung around the pivot
means 23. Accordingly, the angle ~' of the shearing
edge of the upper side blade 17 to the lower side ~lade
21 which is shown in Fig. 3 will be changed as the
ram 13 is rotated or swung around the pivot means 23
to move the upper side blade 17 up and down. Assuming
that angle ~' of the upper side blade 17 to the lower
side blade 21 is negative when the ram 13 is at its
raised position, it will be gradually changed or
increased from ~e negative to zero (0) degree and
tHen become positive as the ram 13 is rotated down-
wardly from the raised position to lower the upper
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side blade 17. Thus, the angle ~' of the upper side
blade 17 to the lower side blade 21 which i5 negati~e
when the ram 13 is at t~e raised position will become
positive when the ram 13 is lowered to bring the upper
side blade 17 into engagement with the lower side blade
21. It wil1 be understood that the angle ~' of the
upper side blade 17 to the lower side blade 21 will
become positive when the ram 13 is lowered, since the
pi~ot means 23 on which the ram 13 is pivotally held
is disposed higher than the level of the top surfaces
of the lower front and side blades 19 and 21 as has
been described hereinbefore. Also, it will be under-
stood that the angle ~' of the upper side blade 17 to
the lower side blade 21 could not become too large
but will be kept within limits when the upper and lower
side blades 17 and 21 are in engagement with each other
to make shearing actions, since the angle ~' has been
originally set to be negative as has ~een described
hereinbefore.
2Q In operation, the right-hand end Q of the
upper ~ront blade 15 will be initially brought into
contact with the right-hand end of the workpiece W
to be sheared as viewed in ~ig. 2 when the ram 13 is
downwardly rotated or swung around the pivot means 23.
As the ram 13 is further rotated downwardly, the upper
front blade 15 will gradually shear the workpiece W
leftward from the right-hand end Q to the intersecting
point P of the upper front and side blades 15 and 17
in cooperation with the lower front blade 19. It will
3Q be understood that the upper front blade 15 will shear
the workpiece W in cooperation with the lower front
blade 19 at the angle ~ which is originally set to
make the most preferable shearing actions. Also,
when the ram 13 is lowered to enable the upper and
lower front blades 15 and 19 to finish shearing the
workpiece W, of course the intersecting point P
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of the upper front and side blades 15 and 17 has been
brou~ht into contact with the workpiece W. Accordingly,
as soGn as the upper and lower front blades 15 and 19
has finished shearing the workpiece W, the upper side
blade 17 can begin to shear the workpiece W gradually
rearwardly from the intersecting point P to the rear
end R in cooperation with the lower side blade 21 as
the ram 13 is further rotated downwardly on the pivot
means 23. Of course, the upper side blade 17 will
shear the workpiece W in cooperation wi~h the lower
side blade 21 at the angle ~' which is kept within limits
without becoming too large as has been described
hereinbefore.
In this connection, the upper and lower side
blades 17 and 21 can be made idle so that only the
upper and lower front blades 15 and 19 will make
shearing actions when the lower limit of the stroke
of the ram 13 is set higher in a prior art manner.
Thus, even if the workpiece W is larger in width than
the length of the upper and lower front blades 15 and 17,
it can be straightly sheared or slit when it is ~ed
little by little along the upper and lower front blades
15 and 17 with the ram 13 continuously stroked at a
raised position.
As has been described in the above, the angle
~' of the upper side blade 17 to the lower side blade
21 will be kept within limits without becoming too
large when the upper and lower side blades 17 and 21
are in engagement with each other to shear the work-
piece ~. Also, the upper front blade 15 will be inengagement with the lower front blade 19 always at the
angle ~ which has been originally set mcst preferable
when shearing the workpiece W. Thus, the workpiece W
can be accurately sheared by the upper and lower front
blades 15 and 19 and the upper and lower side blades
17 and 21 into blanks without warping and twisting.
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Referring to Figs. 2 and 5, the upper and
lower side blades 17 and 21 are so disposed as to be
located outside of the vertical plane of the outer side
of the upright plate 3. Therefore, the left-hand ends
of the upper and lower front blades 15 and 19 which are
connected to the upper and lower side blades 17 and ~1,
respectively, are also so arranged as to extend or
protrude from the vertical plane of the outer side of
the upright plate 3.
In the above described arrangement, the
workpiece ~ can be sheared without being obstructed by
the upright plate 3 at the throat 3t thereof, even i:E
it is wider than the horizontal length L of the throats
3t and 5t of the upright plates 3 and 5. Stated
otherwise, the workpiece W can be fed rearward of the
rear ends of the throats 3t and 5t of the upright
plates 3 and 5 to be sheared by the upper and lower
front blades 15 and 19 and the upper and lower side
blades 17 and 21. For instance, when the workpiece W
which is wider than the length L of the throats 3t
and 5t of the upright plates 3 and 5 is sheared into
h, B and C as shown in Fig. 5, the left-hand portion
of the workpiece W can be moved rearward along the
outside of the upright plate 3 without being obstructed
thereby. It will be understood that the workpiece W
is sheared into -the blanks A, B and C so that the
left-hand remaining portion of the workpiece W can be
moved rearward along the outside of the upright plate
3, since the upper and lower side blades 17 and 21
a'^e located outside of the vertical plane of the
outer side of the upright plate 3 together with the
left-hand ends of the upper and lower front blades
15 and 19.
In this connectiont it is to be noted that the
purpose of the invention described immediately above
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can be attained even if the ram 13 is so arranged as
to be vertic~lly; moved up and down along vertical
guide means instead of being rotated or swung around
the pivot means 23. In other words, the upper and
lower side blades 17 and 21 can be positioned outside
of the vertical plane of the outer side of the upright
plate 3 even if the ram 13 is so arranged as to be
vertically moved, although the ram 13 has been
described hereinbefore as being rotated or swung around
the pivot means 23.
Although a preferred form of the present
invention has been illustrated and described, it shoul.d
be understood that the device is capable of modification
by one skilled in the art without departing from the
principles of the invent;on. Accordingly, the scope
of the invention is to be l~ted only by the claim
appended thereto.
