TECHNICAL FIELD OF THE INVENTION
[0001] The present invention relates to a knife folding machine for folding a sheet, a sheet
bundle and the like with a knife blade.
BACKGROUND OF THE INVENTION
[0002] A conventional knife folding machine generally comprises a table on which a sheet
bundle is placed; a positioning means for positioning the sheet bundle at a predetermined
folding position on the table; a knife blade; a pair of folding rollers opposed to
the knife blade with the table therebetween at the folding position; and a slider
crank mechanism. The slide crank mechanism reciprocates the knife blade between a
first position and a second position through an opening for passing the knife blade.
The opening is formed on the table. The first position is opposed to the rollers with
the table therebetween and spaced from the table. The second position is disposed
adjacent a gap between the rollers (also see, for example, Patent Documents 1 and
2).
[0003] The knife blade has one end fixed to a rod which is connected with a crank of the
slider crank mechanism. During one revolution of the crank, the knife blade reciprocates
between the first position (upper dead point) and the second position (lower dead
point) so as to cause a folding operation. While the knife blade moves from the first
position to the second position, the sheet bundle on the table is folded in two by
the knife blade, then an edge of the folded portion thereof is pushed out of the opening
and inserted into the gap between the folding rollers so that the sheet bundle can
be folded by the folding rollers.
[0004] By the way, the sheet bundle consists of several sheets, and the thickness of each
sheet and the number of sheets respectively varies depending on the kind of the sheet
bundle so that the thickness of the sheet bundle varies. The second position of the
knife blade should be adjusted in such a way that a distance between the second position
and the gap is optimized. Because when the second position is too far away from the
gap, the sheet bundle cannot be inserted into the gap. When the second position is
too close to the gap, the knife blade enters the gap and stops the knife folding machine.
[0005] In the case of the conventional knife blade machine, the second position of the knife
blade is adjusted by changing the position of the upper dead point of the slider crank
mechanism. In this case, the change of the second position of the knife blade automatically
effects the change of the first position since the stroke of the slider crank mechanism
between the upper and lower dead points is constant.
[0006] In order to achieve a high-speed folding operation, it is preferable that the stroke
of the reciprocal movement of the knife blade is changeable depending on the kind
of the sheet bundle, that is, the first and second positions of the knife blade are
separately changeable. However, in the conventional knife blade, the first and second
positions of the knife blade cannot separately be changeable.
[0007] In addition, a rod is constantly subjected to an offset load in a direction away
from the axis thereof during the folding operation since the slider crank mechanism
transforms a rotary movement of a crank into a reciprocal linear movement of a rod,
which leads to the deterioration of the durability of the knife folding machine.
In the conventional knife folding machine, when each sheet bundle is sequentially
fed to the fold position every time each of the folding operations is completed, an
overload of the knife blade cannot be detected during the folding operation even if
a plurality of sheet bundles are accidentally fed at a time. As a result, the movement
of the knife blade cannot be stopped but continued to cause a paper jam between the
folding rollers, and the folding operation is interrupted for a long time.
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0009] It is an object of the present invention to provide a knife folding machine which
can separately change the positions of the opposite ends of the reciprocal movement
of the knife blade, and achieve a high-speed folding operation and an excellent durability.
It is another object of the present invention to provide a knife folding machine having
the function of detecting the overload of the knife blade during the folding operation.
SOLUTION TO THE PROBLEMS
[0010] In order to achieve the objects, the present invention provides a knife folding machine,
comprising:
a frame having a support surface to support a lower surface of a sheet or a sheet
bundle;
a positioning means attached to the frame to position the sheet or the sheet bundle
at a fold position on the support surface;
a knife blade;
a pair of folding rollers opposed to the knife blade with the support surface therebetween
at the fold position, the folding rollers being attached to the frame, the knife blade
and the folding rollers being disposed in parallel to each other, an edge of the knife
blade being opposed to a gap between the folding rollers, the support surface having
a opening through which the knife blade passes;
a knife drive unit for reciprocating the knife blade in a direction perpendicular
to the support surface through the opening between a first position and a second position,
the first position being opposed to the folding rollers with the support surface therebetween
and spaced from the support surface, the second position being disposed adjacent the
gap between the folding rollers;
a support arm attached to the frame to support the knife drive unit; and
a control unit for controlling the knife drive unit; wherein
the reciprocal movement of the knife blade between the first and second positions
effects a folding operation, wherein
while the knife blade moves from the first position to the second position, the sheet
or the sheet bundle on the support surface being folded in two by the knife blade,
an edge of the folded portion thereof being pushed out of the opening and inserted
to the gap between the folding rollers so that the sheet or the sheet bundle can be
folded by the folding rollers; and wherein
the knife drive unit comprises:
a holder attached to the support arm;
a rod extending in a direction perpendicular to the support surface and attached to
the holder to reciprocate in an axial direction thereof, the rod having one end attached
to the knife blade;
a block attached to a center portion of the rod;
a feed screw extending in parallel to the rod and attached to the holder to rotate
around an axis thereof, the block having a thorough hole which has thread grooves
corresponding to the feed screw, the feed screw engaging with the through hole, the
rod being reciprocated by the rotation of the feed screw;
a first pulley attached to an upper or lower end of the feed screw;
a servomotor attached to the holder and having a drive shaft, the drive shaft extending
in parallel to the feed screw;
a second pulley attached to the drive shaft of the servomotor; and
a timing belt extended between the first and second pulleys, the servomotor being
controlled by the control unit.
[0011] According to a preferred embodiment of the present invention, the control unit comprises:
a first input portion for receiving input of both a data of a distance (d1) from the
support surface to the first position and a data of a distance (d2) from the support
surface to the second position; and
a first memory for storing the datum of the distances (d1, d2) inputted through the
first input portion; and wherein
the control unit controls the servomotor based on the datum of the distances (d1,
d2) stored in the first memory.
[0012] According to further preferred embodiment of the present invention, the knife folding
machine further comprising:
a feed means attached to the frame to sequentially feed the sheet or the sheet bundle
to the fold position in a direction parallel or perpendicular to the knife blade on
the support surface; wherein
the positioning means comprises a stopper disposed on a downstream side of the knife
blade and extending in a direction perpendicular to a feed path of the sheet or the
sheet bundle on the support surface, the stopper positioning the sheet or the sheet
bundle at the fold position by the abutment of the front end of the sheet or the sheet
bundle against the stopper.
[0013] According to further preferred embodiment of the present invention, the knife folding
machine further comprising:
a sensor disposed in the middle way of the feed path of the sheet or the sheet bundle
to detect a passage of a tail end of the sheet or the sheet bundle; wherein
the stopper is movable along the feed path in a direction of toward and away from
the sensor and disposed away from the sensor a distance (r) summed up in both of a
distance (p) along the feed path of the sheet or the sheet bundle and a predetermined
distance (q); wherein
the control unit comprises:
a second input portion for receiving input of a data of a delay time from when the
tail end of the sheet or the sheet bundle (S) passes through the sensor till when
the folding operation of the knife blade (5) starts; and
a second memory for storing the data of the delay time (t) inputted through the second
input portion; and wherein
the control unit controls the servomotor of the knife drive unit based on a detecting
data from the sensor and the data of the delay time (t) stored in the second memory.
[0014] According to further preferred embodiment of the present invention, the feed means
comprises:
a drive roller and an idle roller attached to the frame and spaced from and in parallel
to each other;
at least one conveyer belt extending between the drive roller and idle roller; and
a second servomotor attached to the frame to rotate the drive roller; wherein
a part of the support surface is formed by a feed surface of the conveyer belt, each
of rotation shafts of the drive roller and idle roller being disposed in parallel
or vertical to the knife blade.
EFFECT OF THE INVENTION
[0015] The knife folding machine of the present invention comprises the rod supported to
reciprocate in a direction perpendicular to the support surface for supporting the
lower surface of the sheet or the sheet bundle, and the feed screw disposed in parallel
to the rod and supported to rotate around an axis thereof. The rod and the feed screw
are operatively connected with each other by the block. The rod is fixed to the knife
blade at its one end and reciprocated by the feed screw. The feed screw is rotated
by the servomotor. Thus the knife blade reciprocates between the first and second
positions. As a result, it is possible to easily adjust the stroke of the reciprocal
movement of the knife blade, and separately adjust the first and second positions
thereof by controlling the amount of the rotation of the servomotor.
[0016] Further in the present invention, the rod is not be subjected to the offset load
in a direction away from the axis thereof during the folding operation because the
rod and the feed screw are disposed in parallel to each other, so that the durability
of the knife folding machine improves. Since the rod, or the knife blade is reciprocated
by the feed screw which is rotated by the servomotor, the overload subjected to the
knife blade can be detected by the servomotor. As a result, when each sheet bundle
is sequentially fed to the fold position every time each of the folding operations
is finished, the paper jam is avoided by stopping the knife blade in the course of
its folding operation even if a plurality of sheet bundles are accidentally fed at
a time.
BRIEF DESCRIPTION OF THE DRAWING
[0017]
Fig. 1 is a perspective view showing a knife folding machine according to the first
embodiment of the present invention, in which no sheet is set at a fold position of
the knife folding machine.
Fig. 2 is a perspective view showing the knife folding machine according to the first
embodiment of the present invention, in which a sheet is set at the fold position
of the knife folding machine.
Fig. 3 is a perspective view showing a knife drive unit of the knife folding machine
of Fig. 1.
Fig. 4A is a front view showing the knife drive unit of the knife folding machine
of Fig. 1 when a knife blade is disposed at a first position.
Fig. 4B is a front view showing the knife drive unit of the knife folding machine
of Fig. 1 when the knife blade is disposed at a second position.
Fig. 5 is a plan view showing a touch screen as a first and second input portions
of the knife folding machine of Fig. 1.
DETAILED EXPLANATION OF THE PREFERRED EMBODIMENTS
[0018] A preferred embodiment of the present invention will be explained below with reference
to the accompanying drawings. Fig. 1 is a perspective view showing a knife folding
machine according to the first embodiment of the present invention, in which no sheet
is not set at a fold position of the knife folding machine. Fig. 2 is a perspective
view showing the knife folding machine according to the first embodiment of the present
invention, in which a sheet is set at the fold position of the knife folding machine.
As shown in Figs. 1 and 2, the knife folding machine of the present invention comprises
a frame 1. A plurality of elongated plates 2, 2a are attached to the upper surface
of the frame 1 and spaced from each other widthwise. The upper surfaces of these plates
2, 2a construct a part of a support surface 4 for supporting a lower surface of a
sheet or a sheet bundle (hereinafter generically referred to as "a sheet S").
[0019] A pair of folding rollers 6a, 6b are opposed to a knife blade 5 with the support
surface 4 therebetween at the fold position on the support surface 4. In this embodiment,
the knife blade 5 is disposed above the center plate 2a (the support surface 4) and
the folding rollers 6a, 6b are disposed below the center plate 2a. In another embodiment,
the knife blade 5 may be disposed below the center plate 2a and the folding rollers
6a, 6b may be disposed above the center plate 2a.
[0020] The folding rollers 6a, 6b are attached to the frame 1. The knife blade 5 and the
folding rollers 6a, 6b are disposed in parallel to each other and the center plate
2a. A opening 3 is formed on the center plate 2a and extends longitudinally thereof.
The knife blade 5 passes through the opening 3 and one end of the knife blade 5 is
opposed to a gap between the folding rollers 6a, 6b.
[0021] The knife folding machine comprises a knife drive unit 7. The knife drive unit 7
reciprocates the knife blade 5 between first and second positions through the opening
3 in a direction perpendicular to the support surface 4. The first position is spaced
from and above the support surface 4. The second position is disposed adjacent the
gap between the folding rollers 6a, 6b. The knife drive unit 7 is supported on a support
arm 8 attached to the frame 1.
[0022] Fig. 3 is a perspective view showing a knife drive unit of the knife folding machine
of Fig. 1. Fig. 4A is a front view showing the knife drive unit of the knife folding
machine of Fig. 1 when a knife blade is disposed at the first position. Fig. 4B is
a front view showing the knife drive unit of the knife folding machine of Fig. 1 when
the knife blade is disposed at the second position.
As shown in Figs. 3 and 4, the knife drive unit 7 comprises a holder 9 attached to
the support arm 8. The holder 9 has horizontal upper and lower support walls 9a, 9b
which are vertically spaced from each other. A rod 10 extends through the upper and
lower support walls 9a, 9b in a direction vertical or perpendicular to the support
surface 4. The rod 10 is attached to the holder 9 via bearings (not shown) disposed
in the upper and lower support walls 9a, 9b so as to be reciprocated in an axial direction
thereof. The knife blade 5 is fixed on the lower end of the rod 10. A block 11 is
fixed on a center portion of the rod 10 (the portion extends between the upper and
lower support walls 9a, 9b).
[0023] A feed screw 12 is attached to rotate around an axis thereof and extends in parallel
to the rod 10 between the upper and lower support walls 9a, 9b of the holder 9. The
block 11 has a through hole which provided with thread grooves corresponding to the
feed screw 12. The feed screw 12 is engaged with the through hole. While the feed
screw 12 rotates, the rod 10 reciprocates in a direction perpendicular to the support
surface 4 through the block 11.
[0024] The knife drive unit 7 further comprises a first pulley 13 attached to an upper end
of the feed screw 12, a servomotor 14 attached to holder 9 and having a drive shaft
14a in parallel to the feed screw 12, a second pulley 15 attached to the drive shaft
14a of the servomotor 14, and a timing belt 16 extended between the first and second
pulleys 13,15.
[0025] In this embodiment, the first pulley 13 is attached to the upper end of the feed
screw 12 and driven by the servomotor 14, but the first pulley 13 may be attached
to the lower end of the feed screw 12 and driven by the servomotor 14.
[0026] The servomotor 14 is controlled by a control unit 22.
The control unit 22 comprises a first input portion 23 for receiving input of both
a data of a distance d1 (see Fig. 4A) from the support surface 4 to the first position
and a data of a distance d2 (see Fig. 4B) from the support surface 4 to the second
position. The control unit 22 comprises a first memory 24 for storing the datum of
the distances d1, d2 through the first input portion 23.
[0027] In this embodiment, as shown in Fig. 5, the first input portion 23 is formed by a
lower input area 29a of a touch screen 29. In this embodiment, the lower input area
29a receives input of values corrected for default values respectively corresponding
to distances from the support surface 4 to the first and second positions. Thus the
distance d1 from the support surface 4 to the first position and the distance d2 from
the support surface 4 to the second position are inputted. In the lower input area
29a there are upper and lower numerical value columns 30a, 30b. The upper numerical
value column 30a indicates the corrected value of the distance from the first position
to the support surface 4 by 0.1 mm. The lower numerical value column 30b indicates
the corrected value of the distance from the second position to the support surface
4 by 0.1mm.
At the right side of the numerical value columns 30a, 30b, there are a "+" button
for increasing the corrected value, a "-" button for decreasing the corrected value,
and a "D" button for changing the corrected value to zero. Each of the corrected values
can easily be inputted by depressing these buttons.
[0028] The control unit 22 calculates an amount of the rotation of the servomotor 14 corresponding
to the distance from the first position to the second position based on the datum
of the distances d1, d2 stored in the first memory 24 and controls the servomotor
14.
The servomotor 14 rotates the feed screw 12 to reciprocate the rod 10 or the knife
blade 5 between the first position (see Fig. 4A) and the second position (see Fig.
4B) via the block 11.
[0029] The reciprocal movement of the knife blade 5 between the first and second positions
effects a folding operation. While the knife blade 5 moves from the first position
to the second position, the sheet S on the support surface 4 is folded in two by the
knife blade 5, and an edge of the folded portion thereof is pushed out of the opening
3 and inserted to the gap between the folding rollers 6a, 6b so that the sheet S can
be folded by the folding rollers 6a, 6b.
[0030] According to the present invention, the servomotor 14 rotates the feed screw 12 to
reciprocate the rod 10 or the knife blade 5 between the first and second positions.
As a result, the stroke of reciprocal movement of the knife blade 5 can easily be
adjusted, and the first and second positions of the knife blade 5 can separately be
adjusted by controlling the amount of the rotation of the servomotor 14.
[0031] Further in the present invention, the rod 10 is not subjected to the offset load
in a direction away from the axis thereof during the folding operation because the
rod 10 and the feed screw 12 are disposed in parallel to each other, so that the durability
of the knife folding machine can be improved. Since the rod 10 or the knife blade
5 is reciprocated by the feed screw 12 which is rotated by the servomotor 14, the
overload subjected to the knife blade 5 is detected by the servomotor 14. As a result,
when each sheet S is sequentially fed to the fold position every time each of the
folding operations is finished, the paper jam between the folding rollers 6a, 6b can
be avoided by stopping the knife blade 5 in the course of its folding operation even
if a plurality of sheets S are accidentally fed at one time.
[0032] The knife folding machine further comprises a feed means attached to the frame 1
to sequentially feed the sheet S to the fold position in a direction parallel to the
knife blade 5 on the support surface 4.
In this embodiment, the feed means comprises a drive roller 17 and an idle roller
18 which are attached to the frame 1 and respectively disposed on one and the other
end sides of the frame 1 below the support surface 4 (plates 2, 2a). Each of rotation
shafts of the drive roller 17 and the idle roller 18 is disposed in parallel to each
other and extends in a direction perpendicular to the knife blade 5. The drive roller
17 is driven by a second servomotor 19 fixed to the frame 1. The second servomotor
19 is controlled by the control unit 22.
[0033] A plurality of conveyer belts 20 extend between the drive roller 17 and the idle
roller 18. Two conveyer belts 20 are arranged for each of the plates 2, 2a and spaced
from each other. Each of upper side portions of the conveyer belts 20 is disposed
above the plates 2, 2a. As a result, a part of the support surface 4 is formed by
a feed surface of the conveyer belt 20.
[0034] The knife folding machine further comprises a positioning means attached to the frame
1 to position the sheet S at the fold position on the support surface 4. In this embodiment,
the positioning means comprises a stopper 21 disposed at a downstream side of the
knife blade 5 and extending in a direction perpendicular to a feed path of the sheet
S on the support surface 4. The stopper 21 positions the sheet S at the fold position
by the abutment of the front end of the sheet S against the stopper 21.
A horizontal support bar 27 is attached to the frame 1 at its opposed ends and extends
in a direction perpendicular to the feed path of the sheet S at an upstream side of
the opening 3 of the plate 2a. A sensor 28 is attached to the center of the support
bar 27 to detect a passage of a tail end of the sheet S.
The stopper 21 is movable along the feed path of the sheet S in a direction of toward
and away from the sensor 28. The stopper 21 is disposed away from the sensor 28 by
a distance (r) summed up in both of a distance (p) along the feed path of the sheet
S and a predetermined distance (q).
[0035] After the passage of the tail end of the sheet S, the control unit 22 controls the
second servomotor 19 by lowering the rotary speed of the second servomotor 19 in such
a way that the feed speed of the sheet S gradually lowers so as to become the slowest
speed just before the abutment of the sheet S against the stopper 21.
[0036] The control unit 22 comprises a second input portion 25 for receiving input of a
data of a delay time (t) from when the tail end of the sheet S passes through the
sensor 28 till when the folding operation of the knife blade 5 starts, and a second
memory 26 for storing the data of the delay time (t) inputted through the second input
portion 25.
In this embodiment, as shown in Fig. 5, the second input portion 25 is formed by an
upper input area 29b of a touch screen 29. In the upper input area 29b there is a
display portion for indicating a set value of the delay time (t) in a step-by-step
manner. At the right side of the display portion there is a "+" button for increasing
the set value, meanwhile, at the left side thereof there is a "-" button for decreasing
the set value. The set values can easily be inputted by depressing these buttons on
the microsecond time scale.
[0037] The delay time (t) is a time from when the tail end of the sheet S passes through
the sensor 28 till when the sheet S rebounds from the stopper 21 and stops. By use
of the delay time (t) the knife blade 5 can work the sheet S only when the sheet S
completely stops after its abutment against the stopper 21 and rebound, so that the
sheet S can be correctly folded.
[0038] Thus before the folding operation of the knife blade machine starts, the stopper
21 is disposed away from the sensor 28 by a distance (r) summed up in both of a distance
(p) along the feed path of the sheet S and a predetermined distance (q). The set value
of the distance (d1) from the support surface 4 to the first position, the set value
of the distance (d2) from the support surface 4 to the second position and the set
value of the delay time (t) are inputted through the touch screen 29, respectively.
The knife blade 5 moves to the first position based on the set value of the distance
(d1) so as to be kept in a standby condition.
[0039] Then the folding operation of the knife folding machine starts. The first sheet S
is conveyed to the fold position by the conveyer belts 20. When the sensor 28 detects
the passage of the tail end of the sheet S, the control unit 22 starts the time measurement
after the passage of the sheet S through the sensor 28, and at the same time gradually
slows the feed speed of the sheet S. The sheet S abuts against and rebounds from the
stopper 21, and then stops at the fold position (see Fig. 2). Soon after that, the
control unit 22 detects the delay time (t) after the passage of the sheet S through
the sensor 28 and the folding operation starts, so that the knife blade 5 is moved
from the first position to the second position.
[0040] During the movement, the sheet S on the support surface 4 is folded in two by the
knife blade 5, and the edge of the folded portion of the sheet S is pushed out of
the opening 3 and inserted to the gap between the folding rollers 6a, 6b so that the
sheet S can be folded by the folding rollers 6a, 6b. Then the knife blade 5 returns
from the second position to the first position. During the reciprocal movement of
the knife blade 5 between the first and second positions, the folding operation is
caused. The next sheet S is conveyed by the conveyer belts 20 to be fed to the fold
position every time each of the folding operations is completed.
DESCRIPTION OF THE REFERENCE CHARACTERS
[0041]
1 frame
2 plate
2a center plate
3 opening
4 support surface
5 knife blade
6a, 6b folding rollers
7 knife drive unit
8 support arm
9 holder
9a upper support wall
9b lower support wall
10 rod
11 block
12 feed screw
13 first pulley
14 servomotor
14a drive shaft
15 second pulley
16 timing belt
17 drive roller
18 idle roller
19 servomotor
20 conveyer belt
21 stopper
22 control unit
23 first input portion
24 first memory
25 second input portion
26 second memory
27 support bar
28 sensor
29 touch screen
29a lower input area
29b upper input area
30a, 30b numerical value column
S sheet
1. A knife folding machine, comprising:
a frame (1) having a support surface (4) to support a lower surface of a sheet or
a sheet bundle (S);
a positioning means attached to the frame (1) to position the sheet or the sheet bundle
(S) at a fold position on the support surface (4);
a knife blade (5);
a pair of folding rollers (6a, 6b) opposed to the knife blade (5) with the support
surface (4) therebetween at the fold position, the folding rollers (6a, 6b) being
attached to the frame (1), the knife blade (5) and the folding rollers (6a, 6b) being
disposed in parallel to each other, an edge of the knife blade (5) being opposed to
a gap between the folding rollers (6a, 6b), the support surface (4) having a opening
(3) through which the knife blade (5) passes;
a knife drive unit (7) for reciprocating the knife blade (5) in a direction perpendicular
to the support surface (4) through the opening (3) between a first position and a
second position, the first position being opposed to the folding rollers (6a, 6b)
with the support surface (4) therebetween and spaced from the support surface (4),
the second position being disposed adjacent the gap between the folding rollers (6a,
6b);
a support arm (8) attached to the frame (1) to support the knife drive unit (7); and
a control unit (22) for controlling the knife drive unit (7); wherein
the reciprocal movement of the knife blade (5) between the first and second positions
effects a folding operation, wherein
while the knife blade (5) moves from the first position to the second position, the
sheet or the sheet bundle (S) on the support surface (4) being folded in two by the
knife blade (5), an edge of the folded portion thereof being pushed out of the opening
(3) and inserted to the gap between the folding rollers (6a, 6b) so that the sheet
or the sheet bundle (S) can be folded by the folding rollers (6a, 6b); and wherein
the knife drive unit (7) comprises:
a holder (9) attached to the support arm (8);
a rod (10) extending in a direction perpendicular to the support surface (4) and attached
to the holder (9) to reciprocate in an axial direction thereof, the rod (10) having
one end attached to the knife blade (5);
a block (11) attached to a center portion of the rod (10);
a feed screw (12) extending in parallel to the rod (10) and attached to the holder
(9) to rotate around an axis thereof, the block (11) having a thorough hole which
has thread grooves corresponding to the feed screw (12), the feed screw (12) engaging
with the through hole, the rod (10) being reciprocated by the rotation of the feed
screw (12);
a first pulley (13) attached to an upper or lower end of the feed screw (12);
a servomotor (14) attached to the holder (9) and having a drive shaft (14a), the drive
shaft (14a) extending in parallel to the feed screw (12);
a second pulley (15) attached to the drive shaft (14a) of the servomotor (14); and
a timing belt (16) extended between the first and second pulleys (13, 15), the servomotor
(14) being controlled by the control unit (22).
2. The knife folding machine according to claim 1, wherein
the control unit (22) comprises:
a first input portion (23) for receiving input of both a data of a distance (d1) from
the support surface (4) to the first position and a data of a distance (d2) from the
support surface (4) to the second position; and
a first memory (24) for storing the datum of the distances (d1, d2) inputted through
the first input portion (23); and wherein
the control unit (22) controls the servomotor (14) based on the datum of the distances
(d1, d2) stored in the first memory (24).
3. The knife folding machine according to claim 2, further comprising:
a feed means attached to the frame (1) to sequentially feed the sheet or the sheet
bundle (S) to the fold position in a direction parallel or perpendicular to the knife
blade (5) on the support surface (4); wherein
the positioning means comprises a stopper (21) disposed on a downstream side of the
knife blade (5) and extending in a direction perpendicular to a feed path of the sheet
or the sheet bundle (S) on the support surface (4), the stopper (21) positioning the
sheet or the sheet bundle (S) at the fold position by an abutment of a front end of
the sheet or the sheet bundle against the stopper (21).
4. The knife folding machine according to claim 3, further comprising:
a sensor (28) disposed in the middle way of the feed path of the sheet or the sheet
bundle (S) to detect a passage of a tail end of the sheet or the sheet bundle (S);
wherein
the stopper (21) is movable along the feed path in a direction of toward and away
from the sensor (28) and disposed away from the sensor (28) by a distance (r) summed
up in both of a distance (p) along the feed path of the sheet or the sheet bundle
(S) and a predetermined distance (q); wherein
the control unit (22) comprises:
a second input portion (25) for receiving input of a data of a delay time (t) from
when the tail end of the sheet or the sheet bundle (S) passes through the sensor (28)
till when the folding operation of the knife blade (5) starts; and
a second memory (26) for storing the data of the delay time (t) inputted through the
second input portion (25); and wherein
the control unit (22) controls the servomotor (14) of the knife drive unit (7) based
on a detecting data from the sensor (28) and the data of the delay time (t) stored
in the second memory (26).
5. The knife folding machine according to claim 4, wherein
the feed means comprises:
a drive roller (17) and an idle roller (18) attached to the frame (1) and spaced from
and in parallel to each other;
at least one conveyer belt (20) extending between the drive roller (17) and idle roller
(18); and
a second servomotor (19) attached to the frame (1) to rotate the drive roller (17);
wherein
a part of the support surface (4) is formed by a feed surface of the conveyer belt
(20), each of rotation shafts of the drive roller (17) and idle roller (18) being
disposed in parallel or vertical to the knife blade (5).