Technical Field
[0001] The present invention relates to a processing apparatus for intermittently halting
and processing, at a predetermined processing position, a belt-like work that is continuously
carried in a predetermined direction along which a plurality of processing positions
are lined up.
Background Art
[0002] Conventional production lines for disposable diapers, for example, include a plurality
of processing positions aligned front-to-rear along the horizontal direction. Semi-finished
diapers are carried continuously in the state of a continuously-formed belt-like work
in the above-mentioned front/rear direction, and during this course, various processes
are applied thereto at the respective processing positions and the work is finally
cut into units of products, thereby completing finished products.
[0003] In cases where press-working is to be applied at one of the above-mentioned processing
positions, carrying of the belt-like work will be intermittently halted with every
die-pressing motion using press dies. This halt, however, affects the carrying at
processing positions immediately upstream and downstream of the press-working position.
That is, it is inevitable that the belt-like work will temporarily be halted also
at the immediately adjacent processing positions.
[0004] In this regard, a processing apparatus 90 disclosed in Japanese Patent No.
3452577 allows to intermittently halt the carrying of the belt-like work 1 only at the processing
apparatus 90, without stopping the carrying thereof at positions upstream and downstream
of the processing apparatus 90.
[0005] Describing this in detail, as shown in Fig. 1, the processing apparatus 90 has a
pair of rolls 91a, 91b lined up front-to-rear along the horizontal direction. The
belt-like work 1 is wound around the pair of rolls 91a, 91b; thus, loops 1La, 1Lb
consisting of the belt-like work 1 are formed thereon in the front/rear direction,
and rotation of the rolls 91a, 91b causes the belt-like work 1 to be carried forward
at a predetermined carry speed Vt. Further, the pair of rolls 91a, 91b is connected
into a single unit by a separator 93 and is also reciprocatably guided in the front/rear
direction.
[0006] In this example, by translationally moving the pair of rolls 91a, 91b horizontally
at a predetermined moving speed Vm in the rearward direction which is opposite from
the carrying direction of the belt-like work 1 (refer to the chain double-dashed lines
in Fig. 1) during the carrying state of the belt-like work 1, the carry speed Vt and
the moving speed Vm cancel out one another and thus the absolute speed of the belt-like
work 1 in the front/rear direction becomes zero at a position R1 between the pair
of rolls 91a, 91b.
[0007] To make use of the above-described cancel-out relationship, the processing apparatus
90 therefore arranges a processing section 95 in the position R1 between the pair
of rolls 91a, 91b and applies processing using this processing section 95 while moving
the pair of rolls 91a, 91b rearwardly at the above-mentioned moving speed Vm. In this
way, the intermittently-halted state necessary for applying such processing is realized
at the processing apparatus 90, while maintaining the normal continuous-carrying state
at the processing positions upstream and downstream of the processing apparatus 90.
Disclosure of Invention
Problem to be Solved by the Invention
[0008] The processing apparatus 90 of Japanese Patent No.
3452577, however, merely realizes a pseudo-halted state of the belt-like work 1 by the canceling
between the carry speed Vt and the moving speed Vm, without actually halting the carrying
of the belt-like work 1. Therefore, there is a possibility that the belt-like work
1 may slightly shift with respect to the processing section 95 owing to synchronization
failure between the carry speed Vt and the moving speed Vm. In this case, the position
of the processing applied on the belt-like work 1 by the processing section 95 may
deviate from the target position.
[0009] The present invention has been made in view of such a conventional problem as that
described above, and an object thereof is to provide a processing apparatus that processes
a work while intermittently halting the same without affecting the carrying of the
work at upstream and downstream processing positions, and that has superior processing
positional accuracy for processing the work.
Means for Solving the Problem
[0010] A main aspect of the invention for achieving the above-mentioned object is a processing
apparatus for intermittently halting and processing, at a processing position, a belt-like
work that is continuously carried along a predetermined direction, the processing
apparatus including:
a processing section that is provided at the processing position and that performs
the processing on the work while the work is being halted;
an entering-side buffer mechanism that is provided upstream in the predetermined direction
from the processing section and that can accumulate the work carried from upstream;
an exit-side buffer mechanism that is provided downstream in the predetermined direction
from the processing section and that can accumulate the work having been processed
and to be carried downstream; and
a sending section that is provided between the entering-side buffer mechanism and
the processing section and that sends out the work accumulated by the entering-side
buffer mechanism to the processing section;
the sending section,
by restricting the work, halting the work at the processing position, and
performing simultaneously decrease of an accumulation amount of work accumulated by
the exit-side buffer mechanism and increase of an accumulation amount of work accumulated
by the entering-side buffer mechanism in such a manner as the decrease in the accumulation
amount of the exit-side buffer mechanism and the increase in the accumulation amount
of the entering-side buffer mechanism equal to one another;
the sending section,
by canceling the restriction on the work, releasing the halt of the work, and
performing simultaneously increase of the accumulation amount of the exit-side buffer
mechanism and decrease of the accumulation amount of the entering-side buffer mechanism
in such a manner as the increase in the accumulation amount of the exit-side buffer
mechanism and the decrease in the accumulation amount of the entering-side buffer
mechanism equal to one another.
[0011] Other features of the invention will be made clear by the description of the present
specification and accompanying drawings.
Effect of the Invention
[0012] The present invention can provide a processing apparatus that processes a work while
intermittently halting the same without affecting the carrying of the work at upstream
and downstream processing positions, and that has superior processing positional accuracy
for processing the work.
Brief Description of Drawings
[0013]
Fig. 1 is a side view showing an example of a conventional processing apparatus 90.
Fig. 2 is a conceptual diagram of a continuous production line 5 to which a processing
apparatus 10 according to a first embodiment is applied.
Fig. 3 is a side view of the processing apparatus 10 according to the first embodiment.
Figs. 4A to 4C are explanatory diagrams describing an oscillating motion of a seesaw
member 34 during the intermittent halt of a belt-like work 1.
Figs. 5A to 5C are explanatory diagrams describing an oscillating motion of the seesaw
member 34 when the intermittent halt of the belt-like work 1 is released.
Fig. 6 is a chart indicating a rotation speed V of a drive roll 31b.
Fig. 7 is a side view of a processing apparatus 10a according to a second embodiment.
Fig. 8 is a side view of another embodiment of a processing apparatus 10.
List of Reference Numerals
[0014] 1: belt-like work (work); 1a: portion; 1b: portion;
5: continuous production line; 10: processing apparatus;
10a: processing apparatus; 20: press device (processing section);
21a: male die; 21b: female die; 30: intermittent carry device;
31: group of pass-line rolls; 31a: pass-line roll;
31b: drive roll (sending section); 31c: pressing roll;
31d: brake-equipped non-drive roll (sending section);
32: group of pass-line rolls; 32a: pass-line roll;
32b: pass-line roll; 34: seesaw member;
34a: entering-side roll (entering-side buffer mechanism);
34b: exit-side roll (exit-side buffer mechanism);
34c: oscillation central shaft;
36: air cylinder (oscillation drive device);
36a: piston; 41: pressing-motion monitoring sensor;
42: processing-target-section monitoring sensor;
43: oscillating-motion monitoring sensor;
43a: sensor at upper lower-limit position;
43b: sensor at lower lower-limit position;
90: processing apparatus; 91a: roll; 91b: roll; 93: separator;
95: processing section; 1La: loop; 1Lb: loop; Pn-1: processing position;
Pn: processing position; Pn+1: processing position; PL: pass line;
V: carry speed; Vin: entering-side carry speed;
Vout: exit-side carry speed; A1: normal range; A2: deceleration range;
A3: intermittent halt range; A4: acceleration range;
A5: deceleration range; Vt: carry speed; Vm: moving speed; R1: position
Best Mode for Carrying Out the Invention
[0015] At least the following matters will be made clear by the description of the present
specification and the accompanying drawings.
[0016] A processing apparatus for intermittently halting and processing, at a processing
position, a belt-like work that is continuously carried along a predetermined direction,
includes:
a processing section that is provided at the processing position and that performs
the processing on the work while the work is being halted;
an entering-side buffer mechanism that is provided upstream in the predetermined direction
from the processing section and that can accumulate the work carried from upstream;
an exit-side buffer mechanism that is provided downstream in the predetermined direction
from the processing section and that can accumulate the work having been processed
and to be carried downstream; and
a sending section that is provided between the entering-side buffer mechanism and
the processing section and that sends out the work accumulated by the entering-side
buffer mechanism to the processing section;
the sending section,
by restricting the work, halting the work at the processing position, and
performing simultaneously decrease of an accumulation amount of work accumulated by
the exit-side buffer mechanism and increase of an accumulation amount of work accumulated
by the entering-side buffer mechanism in such a manner as the decrease in the accumulation
amount of the exit-side buffer mechanism and the increase in the accumulation amount
of the entering-side buffer mechanism equal to one another;
the sending section,
by canceling the restriction on the work, releasing the halt of the work, and
performing simultaneously increase of the accumulation amount of the exit-side buffer
mechanism and decrease of the accumulation amount of the entering-side buffer mechanism
in such a manner as the increase in the accumulation amount of the exit-side buffer
mechanism and the decrease in the accumulation amount of the entering-side buffer
mechanism equal to one another.
[0017] With such a processing apparatus, the accumulation amount of the entering-side buffer
mechanism and the exit-side buffer mechanism is adjusted as described above. Thus,
the processing apparatus can intermittently halt the work while buffering the influence
of the halting of the work at the processing apparatus through adjustment of the accumulation
amount without causing the influence to spill over to the processing positions located
upstream and downstream of the processing apparatus--i.e., without affecting the carrying
at processing positions upstream and downstream of the processing apparatus whatsoever.
[0018] Further, processing is performed in a state where the carrying of the work is halted
owing to the sending section restricting the work. Therefore, the work is at a complete
stop and will not move, and thus, processing can be applied with high accuracy at
a target position on the work to be processed.
[0019] Furthermore, while the work is being halted, the decrease in the accumulation amount
of the exit-side buffer mechanism and the increase in the accumulation amount of the
entering-side buffer mechanism are kept equal to one another. Therefore, the tension
of the work can be maintained constant even during the halt. On the other hand, the
increase in the accumulation amount of the exit-side buffer mechanism and the decrease
in the accumulation amount of the entering-side buffer mechanism are also kept equal
to one another even when the halt of the work is released. Therefore, the tension
of the work can be maintained constant even during the release.
[0020] In the above processing apparatus, it is preferable that: the sending section is
a roll; and the roll is a drive roll that carries the work to the processing section
by being driven to rotate while winding the work from the entering-side buffer mechanism
around an outer circumferential surface of the roll.
[0021] With such a processing apparatus, the work is wound around the roll and is carried
by the driving rotation of the roll. Therefore, restricting the rotation of the roll
will reliably halt the work, and thus, the work can reliably be brought to a carry-halt
state.
[0022] In the above processing apparatus, it is preferable that: the sending section includes
a roll that is in contact with the work and a pressing roll that is pressed against
an outer circumferential surface of the above-mentioned roll; and the work is carried
sandwiched between the roll and the pressing roll.
[0023] With such a processing apparatus, the responsiveness for halting the carrying of
the work with the roll can be improved.
[0024] In the above processing apparatus, it is preferable that: the entering-side buffer
mechanism accumulates the work carried from upstream by forming a loop consisting
of the work in an intersecting direction that intersects with the predetermined direction;
and the exit-side buffer mechanism accumulates the work having been processed and
to be carried downstream by forming, in the intersecting direction, a loop consisting
of the work having been processed.
[0025] With such a processing apparatus, the direction in which the loops of the entering-side
buffer mechanism and the exit-side buffer mechanism are formed is in the intersecting
direction, which intersects with the predetermined direction. Thus, the processing
apparatus can be kept from becoming large in size in the predetermined direction along
with the formation of the loops. In other words, the entire length of the processing
apparatus can be kept short with respect to the predetermined direction which is the
direction in which the work is carried.
[0026] In the above processing apparatus, it is preferable that the intersecting direction
is a direction orthogonal to the predetermined direction.
[0027] With such a processing apparatus, the entire length of the processing apparatus can
be minimized with respect to the predetermined direction.
[0028] In the above processing apparatus, it is preferable that: the entering-side buffer
mechanism includes an entering-side roll that is reciprocatably guided in the intersecting
direction, and the loop is formed by winding the work around the entering-side roll;
the exit-side buffer mechanism includes an exit-side roll that is reciprocatably guided
in the intersecting direction, and the loop is formed by winding the work having been
processed around the exit-side roll; and the entering-side roll and the exit-side
roll move in the intersecting direction interlocked with one another, and move in
opposite directions from one another at the same speed when moving in the intersecting
direction.
[0029] With such a processing apparatus, the entering-side roll and the exit-side roll carry
out opposite motions with respect to one another in the intersecting direction. Thus,
the total amount of the length of the work accumulated by the entering-side roll and
the length of the work accumulated by the exit-side roll is always kept constant,
regardless of whether the work is being intermittently halted or the halt is released.
Accordingly, it is possible to reliably achieve synchronization between the carry
speed of the work both at positions upstream and downstream of the processing apparatus
while keeping the tension of the work constant. In other words, it is possible to
pass the work having been processed on to the downstream processing position at the
same carry speed as the carry speed of the work received from the upstream processing
position, while effectively reducing any change in tension of the work.
[0030] Incidentally, the above can also be stated as follows. Since the entering-side roll
and the exit-side roll carry out opposite motions with respect to one another in the
intersecting direction, the decrease in the accumulation amount of the exit-side buffer
mechanism and the increase in the accumulation amount of the entering-side buffer
mechanism can be kept equal to one another while the work is being halted, and on
the other hand, the increase in the accumulation amount of the exit-side buffer mechanism
and the decrease in the accumulation amount of the entering-side buffer mechanism
can be kept equal to one another when the halt of the work is released. As a result,
the tension of the work can be maintained constant both during the halt of the work
and during the release of the halt.
[0031] In the above processing apparatus, it is preferable that: the processing apparatus
further includes a seesaw member that oscillates about a predetermined axis, wherein
both the entering-side roll and the exit-side roll are mounted on the seesaw member,
and wherein the axis is located at a midpoint between a position where the entering-side
roll is mounted and a position where the exit-side roll is mounted.
[0032] With such a processing apparatus, the above-mentioned opposite-motion relationship
in the intersecting direction between the entering-side roll and the exit-side roll
can easily be created by the oscillating motion of the seesaw member, thus simplifying
the configuration of the processing apparatus.
[0033] In the above processing apparatus, it is preferable that: the entering-side buffer
mechanism includes a plurality of the entering-side rolls for forming the loop of
the work by winding the work around the entering-side rolls in a zigzag form; and
the exit-side buffer mechanism includes a plurality of the exit-side rolls for forming
the loop of the work having been processed by winding the processed work around the
exit-side rolls in a zigzag form.
With such a processing apparatus, the oscillation stroke amount of the seesaw member
can be reduced, compared to a case where the loops are not formed in a zigzag form,
i.e., a case where one each of the entering-side roll and the exit-side roll is provided
and each roll forms a single loop. Thus, it is possible to reduce the oscillating
motion speed and thereby reduce the impact upon vertically reversing the oscillating
motion.
[0034] In the above processing apparatus, it is preferable that a motion for increasing
the accumulation amount of the exit-side buffer mechanism and a motion for decreasing
the accumulation amount of the entering-side buffer mechanism performed upon releasing
the halt of the work are achieved by making a carry speed at which the work is carried
between the entering-side buffer mechanism and the exit-side buffer mechanism faster
than both a carry speed at which the work is carried on a side upstream from the entering-side
buffer mechanism and a carry speed at which the work having been processed is carried
on a side downstream from the exit-side buffer mechanism.
[0035] With such a processing apparatus, the above-described motions of the entering-side
buffer mechanism and the exit-side buffer mechanism can be achieved reliably while
the halt of the work is released.
=== FIRST EMBODIMENT ===
[0036] Fig. 2 is a conceptual diagram of a continuous production line 5 to which a processing
apparatus 10 according to the present first embodiment is applied. Fig. 3 is a side
view of the processing apparatus 10. Below, the vertical direction is referred to
also as the up/down direction, and the horizontal direction orthogonal to the vertical
direction is referred to also as the front/rear direction. Incidentally, the "front"
of the front/rear direction is the downstream side of the carrying direction of the
belt-like work 1, and the "rear" is the upstream side of the same. Further, the upstream
side of the processing apparatus 10 is referred to also as the entering side, and
the downstream side of the same is referred to also as the exit side.
[0037] As shown in Fig. 2, the continuous production line 5 includes a plurality of processing
positions P1, P2, ... arranged front-to-rear along the horizontal direction, which
serves as a predetermined direction. At each processing position P1, P2, ..., appropriate
processing is successively applied on a semi-finished belt-like work 1 that is carried
continuously, to thereby complete finished products.
[0038] As shown in Fig. 3, the processing apparatus 10 according to the first embodiment
is incorporated into one processing position Pn (in this example, a position for press-working
the belt-like work 1) of the plurality of processing positions P1, P2, ... . The belt-like
work 1 is drawn into the processing apparatus 10 from an immediately upstream processing
position Pn-1 at an entering-side carry speed Vin, and on the other hand, after being
subjected to predetermined processing by the processing apparatus 10, the work is
drawn out toward an immediately downstream processing position Pn+1 at an exit-side
carry speed Vout.
[0039] According to the constant mass flow principle, the entering-side carry speed Vin
and the exit-side carry speed Vout of the processing apparatus 10 should basically
be equal to one another; however, in cases where the belt-like work 1 is a stretchable
material such as nonwoven fabric, the entering-side carry speed Vin and the exit-side
carry speed Vout may differ from one another owing to the stretching deformation of
the material, and for example, the entering-side carry speed Vin may range from 95%
to 105% of the exit-side carry speed Vout. The explanation below, however, is based
on the premise that the entering-side carry speed Vin and the exit-side carry speed
Vout are controlled in such a manner that they are equal to one another and are at
a reference speed V0.
[0040] Incidentally, the processing carried out by the processing apparatus 10 is, for example,
press-working. It is therefore necessary to intermittently halt the carrying of the
belt-like work 1 during this press-working. The processing apparatus 10, however,
is devised so that it can keep the entering-side carry speed Vin and the exit-side
carry speed Vout constant at approximately the above-mentioned reference speed V0,
regardless of the intermittent halt. In other words, this processing apparatus 10
allows intermittent carrying to be performed only at the processing apparatus 10,
while continuously carrying the belt-like work 1 at the immediately upstream and downstream
processing positions Pn-1, Pn+1 without stopping the carrying thereat whatsoever.
The following describes the processing apparatus 10 in detail.
[0041] The processing apparatus 10 includes: a press device 20, which serves as a processing
section, for applying press-working on the belt-like work 1; an intermittent carry
device 30 for intermittently carrying the belt-like work 1 along a horizontal pass
line PL and making the work pass the position of the press device 20 with every pressing
motion of the press device 20; a group of sensors 41, 42, 43 for detecting the state
of the press device 20 and the intermittent carry device 30; and a controller (not
shown) for controlling the press device 20 and the intermittent carry device 30 in
cooperation with one another based on the detection results of the group of sensors
41, 42, 43.
[0042] The press device 20 includes, for example, a male die 21a that can be driven to ascend/descend
up and down in the vertical direction, and a female die 21b arranged below the male
die 21a in opposition thereto. The pass line PL is set between the male and female
dies 21a, 21b with respect to the up/down direction. A section targeted for processing
("processing target section") of the belt-like work 1 is carried in the horizontal
direction along the pass line, and then, while the carrying is being intermittently
halted, the male die 21a descends toward the female die 21b and sandwiches and presses
the processing target section of the belt-like work 1, to thus apply press-working.
When the male die 21a ascends and the pressing motion is finished, the carrying motion
of the belt-like work 1 is resumed, and the press device 20 stays on standby until
the subsequent processing target section of the belt-like work 1 moves below the male
die 21a and halts. Note that in this example, a hydraulic cylinder (not shown) is
employed as a drive source of the ascending/descending motion of the male die 21a,
but the invention is not limited thereto.
[0043] The intermittent carry device 30 includes: groups of pass-line rolls 31, 32 that
form the horizontal pass line PL for the belt-like work 1 with respect to the press
device 20; an entering-side buffer mechanism 34a that is provided on the upstream
side of the press device 20 and that can accumulate the belt-like work 1 in a state
strung like a loop that is convex downward in the vertical direction; and an exit-side
buffer mechanism 34b that is provided on the downstream side of the press device 20
and that can accumulate the press-worked belt-like work 1 in a state strung like a
loop that is convex downward in the vertical direction.
[0044] The groups of pass-line rolls 31, 32 mainly consist, for example, of a pair of pass-line
rolls 31a, 31b arranged at the same height and on the upstream side of the press device
20, and a pair of pass-line rolls 32a, 32b arranged at the same height and on the
downstream side of the press device 20. The belt-like work 1 is passed over and supported
by the pass-line rolls 31a, 31b, 32a, 32b, and thereby the horizontal pass line PL
for the belt-like work 1 is formed stretching across the press device 20 front-to-rear
in the horizontal direction.
[0045] Among these pass-line rolls 31a, 31b, 32a, 32b, only the roll 31b immediately upstream
of the press device 20 (also referred to below as a drive roll) is a drive roll that
can be driven to rotate by a drive source such as a servomotor, and the other rolls
are driven rolls that are not driven. Accordingly, the carry state of the belt-like
work 1 in the press device 20 is controlled by controlling the rotational speed of
the drive roll 31b (which corresponds to a "sending section"). That is, when the drive
roll 31b rotates, the belt-like work 1 in the press device 20 is carried, and on the
other hand, when the drive roll 31b halts, the carrying of the belt-like work 1 in
the press device 20 also halts. With the present processing apparatus 10, since the
above-mentioned press-working is performed under this carry-halt state, the press-working
can be applied accurately at a target position on the belt-like work 1.
[0046] Note that a pressing roll 31c that followingly rotates about a rotation axis parallel
to that of the drive roll 31b is pressed against the outer circumferential surface
of the drive roll 31b at a predetermined pressing pressure. Being sandwiched between
the drive roll 31b and the pressing roll 31c, the belt-like work 1 is carried without
causing any relative slippage with the drive roll 31b. Thus, the responsiveness of
the carrying motion of the belt-like work 1 by the drive roll 31b is improved, and
as a result, the halt position accuracy of the belt-like work 1 is improved.
[0047] The entering-side buffer mechanism 34a and the exit-side buffer mechanism 34b employ,
as their main body, a seesaw member 34 whose respective ends in the front and rear
in the horizontal direction can oscillate up and down about an oscillation central
shaft 34c. The ends of the seesaw member respectively have a pair of rolls 34a, 34b
that are equal in diameter and weight and that are for forming the loops of the belt-like
work 1. In this state, the seesaw member 34 is in balance such that it can rotate
back and forth about the oscillation central shaft 34c that is located in the middle
of the rolls 34a, 34b. The rolls 34a, 34b are respectively located at a position between
the pair of pass-line rolls 31a, 31b and at a position between the pair of pass-line
rolls 32a, 32b. Accordingly, the rolls 34a, 34b respectively have a portion 1a of
the belt-like work 1 passed over between the pair of pass-line rolls 31a, 31b and
a portion 1b of the belt-like work 1 passed over between the pair of pass-line rolls
32a, 32b wound around the respective rolls 34a, 34b from below.
[0048] Therefore, when the seesaw member 34 rotates to oscillate, the amount of the loop
(the accumulation amount) of the belt-like work 1 formed by the descending roll 34b
(34a) increases, thereby accumulating the belt-like work 1; on the other hand, the
amount of the loop (the accumulation amount) of the belt-like work 1 formed by the
ascending roll 34a (34b) decreases, thereby sending out the belt-like work 1. That
is, the roll 34a of the entering-side buffer mechanism and the roll 34b of the exit-side
buffer mechanism always move in an opposite-motion relationship with one another.
As a result, the total amount of the length of the loops formed by these rolls 34a,
34b is always kept constant, and thus, it is possible to reliably achieve synchronization
between the entering-side carry speed Vin and the exit-side carry speed Vout of the
processing apparatus 10 while keeping the tension of the belt-like work 1 constant.
[0049] The following describes this in detail. First, the initial state is a state where
a loop is greatly accumulated on the roll 34b of the exit-side buffer mechanism whereas
there is almost no loop on the roll 34a of the entering-side buffer mechanism, as
shown with the solid lines in Fig. 3. Even if, in this state, the rotation of the
drive roll 31b is restricted by the servomotor and halted in order to intermittently
halt the carrying of the belt-like work 1 in the press device 20, it is still necessary
to send out the belt-like work 1 to the downstream processing position Pn+1 at the
exit-side carry speed Vout, regardless of the halted state. In this case, the roll
34b of the exit-side buffer mechanism (also referred to below as an "exit-side roll")
is raised upward owing to the tension of the belt-like work 1, and thus, the belt-like
work 1 is sent out from the loop of the exit-side buffer mechanism, as shown in Figs.
4A to 4C. In this way, it is possible to send out the belt-like work 1 at the carry
speed Vout equal to the reference speed V0, regardless of the halt of the drive roll
31b.
[0050] On the other hand, at this time, the roll 34a of the entering-side buffer mechanism
(also referred to below as an "entering-side roll") which is at its upper-limit position
descends and accumulates the belt-like work 1, which is carried from the upstream
processing position Pn-1, into a downwardly-convex loop shape while pulling the work
downward, as shown in Figs. 4A to 4C. Note here that the entering-side roll 34a is
also provided on the seesaw member 34, alike the exit-side roll 34b. Therefore, the
descending motion of the entering-side roll 34a takes place simultaneously and in
parallel with the above-mentioned ascending motion of the exit-side roll 34b, as an
opposite motion thereof, without any delay in motion. That is, the entering-side roll
34a descends at the same speed as the ascending speed of the exit-side roll 34b, and
the descending amount thereof is the same as the ascending amount of the roll 34b.
Thus, the amount of the belt-like work 1 accumulated by the roll 34a of the entering-side
buffer mechanism becomes equal to the amount of the belt-like work 1 sent out from
the roll 34b of the exit-side buffer mechanism. As a result, it is possible to make
the entering-side carry speed Vin and the exit-side carry speed Vout almost equal;
in other words, it is possible to reliably achieve synchronization between the entering-side
carry speed Vin and the exit-side carry speed Vout.
[0051] Note that, when this intermittently-halted state is cancelled, the restriction on
the rotation of the drive roll 31b is also cancelled--that is, the rotation is resumed--and
thus, the belt-like work 1 in the press device 20 is carried until it reaches the
subsequent intermittent-halt position. During this carrying, however, it is necessary
to return the seesaw member 34 from the state shown in Fig. 4C to the initial state
shown in Fig. 4A in preparation for the subsequent intermittent halt; this return
to the initial state is achieved by setting the carry speed V of the belt-like work
1 in the press device 20 for the intermittent carrying.
[0052] More specifically, when the intermittent halt is released, the drive roll 31b starts
to rotate again as shown in Fig. 5A. Here, the rotation speed V thereof at this time
is set higher than the entering-side carry speed Vin and the exit-side carry speed
Vout. Accordingly, as shown in Figs. 5A to 5C, the belt-like work 1 in the press device
20 is carried at a speed V faster than the entering-side carry speed Vin and the exit-side
carry speed Vout, and thus, the amount of belt-like work 1 sent out from the entering-side
roll 34a becomes larger than the amount of belt-like work 1 supplied to the entering-side
roll 34a at the entering-side carry speed Vin, thereby making the amount of work at
the entering-side roll run short. As a result, the amount of the loop at the entering-side
roll 34a decreases, and the entering-side roll 34a ascends from its lower-limit position
to its upper-limit position. On the other hand, the belt-like work 1 is sent out from
the exit-side roll 34b, which is at its upper-limit position, at the carry speed Vout.
However, since the belt-like work 1 is supplied to the exit-side roll 34b at a speed
V faster than the carry speed Vout, the belt-like work 1 becomes oversupplied. As
a result, the amount of the loop at the exit-side roll 34b increases, and the exit-side
roll 34b descends from its upper-limit position to its lower-limit position. In other
words, the seesaw member 34 carries out a seesawing motion in which the entering-side
roll 34a ascends and the exit-side roll 34b descends, and in this way, the seesaw
member 34 returns to the above-described initial state.
[0053] As shown in Fig. 3, the group of sensors 41, 42, 43 includes a pressing-motion monitoring
sensor 41 for monitoring the pressing motion of the press device 20, a processing-target-section
monitoring sensor 42 for monitoring the position of the processing target section
on the belt-like work 1, and an oscillating-motion monitoring sensor 43 for monitoring
the oscillating motion of the seesaw member 34.
[0054] The pressing-motion monitoring sensor 41 is, for example, a proximity switch provided
at the upper-limit position of the male die 21a and outputs a detection signal every
time the male die 21a reaches the upper-limit position. The processing-target-section
monitoring sensor 42 is a sensor that is arranged immediately upstream of the press
device 20 and that outputs a detection signal every time the sensor detects a mark
indicating a processing location (referred to below as a "processing-location mark")
formed on the belt-like work 1 at a predetermined pitch. An example thereof includes
a photoelectric tube that outputs a signal having an intensity corresponding to the
amount of light received. The oscillating-motion monitoring sensor 43 is, for example,
a proximity switch provided near the lower-limit position of the exit-side roll 34b
of the seesaw member 34, and the proximity switch outputs a detection signal when
the exit-side roll 34b reaches the lower-limit position. Note here that two positions--an
upper lower-limit position, and a lower lower-limit position situated slightly below
the upper lower-limit position--are set as the lower-limit position, and proximity
switches 43a, 43b are respectively arranged at those positions.
[0055] The controller is a suitable sequencer and/or a computer, and controls the various
drive sources relating to the processing apparatus 10 based on the detection results
output from the above-described group of sensors 41, 42, 43. More specifically, the
controller controls the hydraulic cylinder that drives the male die 21a of the press
device 20 so that it ascends and descends, and controls the rotational speed of the
servomotor, which serves as the drive source of the drive roll 31b.
[0056] With the processing apparatus 10 configured as above, rotating the drive roll 31b
as described below allows the belt-like work 1 to be intermittently carried in the
press device 20 and press-working to be applied to the belt-like work 1 at an appropriate
pitch while maintaining the carry speed Vin, Vout of the belt-like work 1 at the respective
processing positions Pn-1, Pn+1 upstream and downstream of the press device 20 at
the normal reference speed V0.
[0057] Fig. 6 is a chart showing the rotation speed V of the drive roll 31b. The horizontal
axis indicates time, and the vertical axis indicates speed (meters/second). Note that,
since the carrying of the belt-like work 1 in the press device 20 is controlled by
the drive roll 31b, the vertical axis of Fig. 6 also indicates the carry speed V of
the belt-like work 1 for carrying the work in the press device 20.
[0058] First, in the initial state, it is assumed that the entering-side roll 34a and the
exit-side roll 34b of the seesaw member 34 are respectively located at the upper-limit
position and the lower-limit position as shown with the solid lines in Fig. 3, and
the belt-like work 1 in the press device 20 is being carried by the drive roll 31b
at the reference speed V0 equal to the entering-side carry speed Vin and the exit-side
carry speed Vout.
[0059] When a detection signal indicating detection of a processing-location mark on the
belt-like work 1 is transmitted from the processing-target-section monitoring sensor
42 during the normal range A1 of Fig. 6 in which carrying is performed in the initial
state, the controller halts the rotation of the drive roll 31b according to a predetermined
deceleration pattern as shown in the deceleration range A2 of Fig. 6, to thus intermittently
halt the carrying of the belt-like work 1 in the press device 20.
[0060] During this intermittent halt A3, the controller makes the press device 20 perform
its pressing motion (Fig. 4B).
[0061] Note that during this intermittent halt A3, the seesaw member 34 performs its oscillating
motion from the initial state (Fig. 4A) to the opposite state (Fig. 4C) as described
above (that is, the entering-side roll 34a descends while the exit-side roll 34b ascends).
Thus, it is possible to receive the belt-like work 1 sent in from the upstream processing
position Pn-1 at the reference speed V0 in its stretched-out state and to send out
the belt-like work 1 to the downstream processing position Pn+1 at the reference speed
V0. Therefore, the carrying state at the respective upstream and downstream processing
positions Pn-1, Pn+1 is not interrupted whatsoever by the intermittent halt.
[0062] When receiving a signal indicating completion of the pressing motion from the pressing-motion
monitoring sensor 41 after a while, the controller resumes the rotation of the drive
roll 31b. At this time, however, as shown in the acceleration range A4 of Fig. 6,
the controller increases the rotation speed according to a predetermined acceleration
pattern up to a speed faster than the reference speed V0 in order to make the speed
eventually faster than the entering-side carry speed Vin and the exit-side carry speed
Vout, to thus return the seesaw member 34 in the state shown in Fig. 5A back to the
initial state shown in Fig. 5C and prepare for the intermittent halt of the subsequent
pressing motion.
[0063] Note that the fact that the seesaw member has returned to its initial state (Fig.
5C) is detected by the oscillating-motion monitoring sensor 43. This is described
in detail. Immediately before returning to the initial state, the exit-side roll 34b
first passes the position of the sensor 43a at the upper lower-limit position, and
therefore, the sensor 43a at the upper lower-limit position sends a detection signal.
Then, the controller starts to decelerate the drive roll 31b, as shown in the deceleration
range A5 of Fig. 6. Then, when the exit-side roll 34b reaches the lower lower-limit
position and the sensor 43b at the lower lower-limit position sends a detection signal,
the controller sets the rotation speed of the drive roll 31b to the reference speed
V0, which completes a single processing cycle.
[0064] After this, the above-described processing cycle is repeated every time the processing-target-section
monitoring sensor 42 detects a processing-location mark on the belt-like work 1.
=== SECOND EMBODIMENT ===
[0065] Fig. 7 is a side view of a processing apparatus 10a according to a second embodiment.
In the above-described first embodiment, the drive roll 31b controlled the carrying
state of the belt-like work 1 in the press device 20. In the present second embodiment,
the carrying state is controlled by a brake-equipped non-drive roll 31d provided in
place of the drive roll 31b and an oscillation drive device 36 for driving the seesaw
member 34 to oscillate. Note that the features other than the above are almost the
same as those in the first embodiment, and thus explanation thereon is omitted.
[0066] The brake-equipped non-drive roll 31d includes a non-drive roll 31d installed at
the same position as the drive roll 31b in place thereof, and a brake mechanism (not
shown) of, for example, the drum-type or the disk-type for braking the rotation of
the non-drive roll 31d. Accordingly, when the brake mechanism is not in operation,
the non-drive roll 31d rotates along with the carrying of the belt-like work 1 which
is in contact with the roll, whereas when the brake mechanism is in operation, not
only is the roll itself halted, but the belt-like work 1 in contact therewith is also
halted.
[0067] The oscillation drive device 36 is, for example, an air cylinder, and the tip end
of its piston 36a is connected to the seesaw member 34. Thus, by supplying compressed
air (pressurized air) from a predetermined compressed-air source to a cylinder chamber
in the air cylinder via a diverter valve such as a solenoid valve, it is possible
to oscillate the seesaw member 34 up and down via the ascending/descending motion
of the piston 36a.
[0068] The non-drive roll 31d and the oscillation drive device 36 are controlled by the
above-described controller, and thus, the belt-like work 1 is intermittently carried
in the press device 20 as follows.
[0069] As in the above example, explanation is made based on the assumption that the processing
apparatus 10a is in the initial state shown in Fig. 3. More specifically, the entering-side
roll 34a and the exit-side roll 34b of the seesaw member 34 are respectively located
at the upper-limit position and the lower-limit position as shown by the solid lines
in Fig. 7, and the belt-like work 1 in the press device 20 is pulled by the downstream
processing position Pn+1 and thus carried at the reference speed V0 equal to the entering-side
carry speed Vin and the exit-side carry speed Vout.
[0070] When a detection signal indicating detection of a processing-location mark is transmitted
from the processing-target-section monitoring sensor 42 while performing the carrying
in the initial state, the controller activates the brake mechanism to restrict and
stop the rotation of the non-drive roll 31d, to thus intermittently halt the carrying
of the belt-like work 1 in the press device 20.
[0071] Then, during this intermittent halt, the controller makes the press device 20 perform
its pressing motion.
[0072] Note that during this intermittent halt, the cylinder chamber of the air cylinder
36 is cut off from the compressed-air source by the diverter valve and opened to the
atmosphere, and thus, the seesaw member 34 is brought to a state where it can freely
oscillate owing to even the slightest load. Thus, the exit-side roll 34b of the seesaw
member 34 is raised by the tension of the belt-like work 1 and ascends, whereas the
entering-side roll 34a performs the opposite motion and descends. In other words,
the seesaw member 34 performs its oscillating motion from the initial state shown
with the solid lines in Fig. 7 to the opposite state shown with the chain double-dashed
lines. Thus, the seesaw member 34 can receive the belt-like work 1 sent in from the
upstream processing position Pn-1 at the entering-side carry speed Vin in its stretched-out
state and send out the belt-like work 1 to the downstream processing position Pn+1
at the exit-side carry speed Vout. Therefore, the carrying state at the respective
upstream and downstream processing positions Pn-1, Pn+1 is not interrupted whatsoever
by the intermittent halt.
[0073] Then, when receiving a signal indicating completion of the pressing motion from the
pressing-motion monitoring sensor 41, the controller releases the brake on the non-drive
roll 31d (i.e., cancels the restriction on the rotation). Then, the non-drive roll
31d comes to rotate along with the belt-like work 1 carried by being pulled by the
downstream processing position Pn+1. During this carrying, however, it is necessary
to return the seesaw member 34 to the initial state shown with the solid lines (i.e.,
to the state in which the entering-side roll 34a is at the upper-limit position and
the exit-side roll 34b is at the lower-limit position) in preparation for the subsequent
intermittent halt. To do so, the controller switches the diverter valve and supplies
the compressed air from the compressed-air source to the cylinder chamber of the air
cylinder 36, thereby extending the piston 36a of the air cylinder 36 and oscillating
the seesaw member 34, i.e., raising the entering-side roll 34a and lowering the exit-side
roll 34b.
[0074] Note that the fact that the seesaw member has returned to its initial state is detected
by the oscillating-motion monitoring sensor 43. This is described in detail. Immediately
before returning to the initial state, the exit-side roll 34b passes the position
of the sensor 43a at the upper lower-limit position. Therefore, when the sensor 43a
at the upper lower-limit position sends a detection signal, the controller first starts
to decelerate the extending motion of the piston 36a of the air cylinder 36. Then,
when the exit-side roll 34b reaches the lower lower-limit position and the sensor
43b at the lower lower-limit position sends a detection signal, the controller halts
the extending motion of the air cylinder 36, which completes a single processing cycle.
[0075] Incidentally, the above-described second embodiment uses a brake-equipped non-drive
roll 31d for intermittently halting the belt-like work 1 and releasing the same. It
is instead possible to use a simple non-drive roll (driven roll) having no brake mechanism.
In this case, however, a separate mechanism for restricting and halting the belt-like
work 1 becomes necessary. An example thereof may include a nip mechanism that is arranged
immediately downstream of the non-drive roll and that includes a pair of upper and
lower nipping members provided so that they can nip the belt-like work 1 from above
and below. When halting the carrying of the belt-like work 1, the pair of upper and
lower nipping members moves toward one another and nips the belt-like work 1, to thereby
restrict the downstream movement of the belt-like work 1. On the other hand, when
resuming the carrying of the belt-like work 1, the nipping members move away from
one another to thus cancel the nipped state of the belt-like work 1, thereby canceling
the restriction on the movement of the belt-like work 1.
=== OTHER EMBODIMENTS ===
[0076] Although embodiments of the present invention have been described above, the invention
is not limited to those embodiments, and modifications such as those described below
are possible.
[0077] The foregoing embodiments describe, as methods for returning the seesaw member 34
to the initial state, an example in which the drive roll 31b is rotated rapidly, and
an example in which the seesaw member 34 is moved by the air cylinder 36. The invention,
however, is not limited thereto whatsoever, and it is possible, for example, to use
a cam mechanism such as a plate cam to return the seesaw member 34 to the initial
state.
[0078] The foregoing embodiments illustrate a configuration in which the entering-side roll
34a serving as the entering-side buffer mechanism and the exit-side roll 34b serving
as the exit-side buffer mechanism are connected into a single unit by the seesaw member
34. The invention, however, is not limited thereto whatsoever, as long as the two
members carry out opposite motions interlocked with one another. That is, the two
members do not have to be connected together by the seesaw member 34.
[0079] For example, the entering-side roll 34a and the exit-side roll 34b may be configured
so that they are reciprocatably guided in the up/down direction respectively, for
example, by suitable guide rails and that the entering-side roll 34a and the exit-side
roll 34b can ascend/descend up and down by a drive source such as an air cylinder.
However, it is needless to say that, when the entering-side roll 34a and the exit-side
roll 34b move in the up/down direction, the entering-side roll 34a and the exit-side
roll 34b are controlled to move interlocked with one another--i.e., are controlled
to move in opposite directions from one another at the same speed.
[0080] The foregoing embodiments do not particularly describe the materials etc. for the
belt-like work 1. However, any belt-like element having moderate flexibility is applicable,
and examples thereof may include nonwoven fabrics, woven fabrics, sheets, and film-like
elements. Materials therefor may include resins, such as synthetic resins, and pulp.
[0081] The foregoing embodiments give press-working as an example of processing applied
to the belt-like work 1. The invention, however, is not limited thereto whatsoever,
and for example, the processing may include embossing for applying projecting-and-depressed
patterns through pressing with dies, and sealing for melt-joining the belt-like work
1.
[0082] In the foregoing embodiments, one entering-side roll 34a and one exit-side roll 34b
are provided on the seesaw member 34 to thus form a single downwardly-convex loop
on each roll. It is, however, possible to increase the number of loops to two or more.
For example, as shown in Fig. 8, two zigzag loops of belt-like work 1 may be formed
by providing two each of the entering-side rolls 34a and the exit-side rolls 34b on
the seesaw member 34 and providing respective fixed rolls 35 (rolls that are fixed
at a predetermined position so that they do not move) between the entering-side rolls
34a, 34a and between the exit-side rolls 34b, 34b. Note that increasing the number
of loops to two or more allows the stroke amount of the oscillating motion of the
seesaw member 34 to be reduced compared to a case where the number of loops is one,
and thus, it is possible to reduce the oscillating motion speed and thereby reduce
the impact upon vertically reversing the oscillating motion.