BACKGROUND OF THE INVENTION
-
The present invention relates to a drafting apparatus
for a spinning machine, and more particularly, to a drafting
apparatus that includes a gauge adjuster for sliding a
supporting member that supports a bottom roller on a roller
stand to change the position.
-
In a drafting apparatus for a spinning machine, it is
necessary to adjust the distance (gauge) between draft rollers,
gripping force (load) of the draft rollers, distribution of
draft depending on the type of fiber to be spun, the length of
the fiber, the amount of fiber to be supplied, and the degree
of parallelism of the fiber to a tensioning direction, to
impart an optimal draft.
-
A drafting force has a certain limit when a bundle of
fibers having a constant strength is drafted with a certain
roller gripping force. With a roller gauge, which tends to
provide an extremely strong drafting force, the drafting
effect is reduced, which increases the likelihood that draft
spots will occur. Conversely, with an extremely weak drafting
force, the cohesion of fibers is reduced, which causes draft
spots. Therefore, for drafting, the roller gauge, load and
draft are set to provide a proper drafting force based on
experience, experimental spinning and so on.
-
A drafting unit of a drafting apparatus includes a
plurality of positively rotated bottom rollers. Top rollers
are arranged in respective correspondence with the bottom
rollers. The top rollers and bottom rollers are arranged in
pairs to constitute draft rollers. Each of the top rollers is
held in contact with the associated bottom roller. Each of
the bottom rollers is supported by a pair of roller slides and
driven. Each of the roller slides is fixed on a roller stand
such that its position (gauge) can be adjusted.
-
For adjusting and changing the gauge in the drafting
apparatus, bolts securing respective roller slides to their
roller stands are loosened to permit the respective roller
slides to move, so that the distances between a front and a
second bottom roller and between a second and a third bottom
roller are adjusted based on the front bottom roller. The
gauges between the respective bottom rollers are determined by
measuring gaps between the respective roller slides and the
distances between the respective bottom rollers with an
instrument such as a slide caliper or a plate gauge.
-
In multiple-type small-lot productions, the type of
spinning sliver is often changed. It takes much time to
change the roller gauge, since a number of steps are required
as described above. For this reason, apparatuses for
facilitating the gauge adjustment have been proposed.
-
For example, Japanese Unexamined Patent Publication No.
Hei 1-156522 discloses a back roller gauge adjusting mechanism
71 for a spinning machine as illustrated in Fig. 7. In the
adjusting mechanism 71, each back slide 72 is provided with a
swing lever 74 and a swing bar 73. The swing levers 74 are
fixed to a swing shaft 75, which extends in the longitudinal
direction of the spinning machine. The swing shaft 75 is
coupled to a braked motor 77 through ball screws 76, so that
the back slides 72 can be moved in a lateral direction of the
spinning machine. Cylinders 79 are also provided for
fastening or loosening fixing screws (not shown) for fixing
the back slides 72 to the associated roller stand 78. As the
braked motor 77 is driven, each back slide 72 is moved to a
predetermined position on the roller stand 78 by the
associated swing lever 74. Also, fastening and loosening the
fixing screws for fixing the back slides 72 to the roller
stands 78 are performed by levers (not shown) that are driven
by the cylinders 79.
-
Japanese Unexamined Patent Publication No. Hei 9-157965
discloses a drafting apparatus 81, which is illustrated in Fig.
8. This drafting apparatus 81 includes front, middle and back
bearings 82, 83, 84, respectively, which have holes 82a, 83a,
84a for supporting bottom rollers (not shown), and grooves 82b,
83b, 84b for supporting top rollers (not shown), respectively.
The middle bearing 83 and the back bearings 84 are fixed to
connecting rods 86a, 86b with screws 87. The connecting rods
86a, 86b extend in the longitudinal direction of a base 85.
The middle bearing 83 and the back bearings 84 can slide along
a sliding surface 85a formed on the base 85.
-
The front bearing 82 is fixed to the base 85. The base
85 is provided with a clamp 88 behind the rearmost back
bearing 84. The connecting rods 86a, 86b are arranged to move
in a longitudinal direction of the base 85 along guide
portions (not shown) formed on the front bearing 82 and the
clamp 88, and are fixed to the clamp 88 with a clamping screw
89 of the clamp 88. Each connecting rods 86a, 86b is
connected to corresponding bearings 83, 84, respectively. The
connecting rods 86a, 86b include a coupler 90 on the rear side
of the base 85. The coupler 90 includes a threaded hole (not
shown). Each of two screw rods 91 is threaded into the
corresponding threaded hole. Each screw rod 91 is driven by a
corresponding driving rod 92 through a toothed pulley (not
shown) and a toothed belt (not shown). When the screw rods 91
rotate, the corresponding connection rod 86a, 86b is moved in
the longitudinal direction of the base 85. The positions of
the respective bearings 83, 84 are thus changed by the
connecting rods 86a, 86b.
-
The gauge adjusting mechanism 71 of Fig. 7 can move the
back slide 72 to adjust the gauge without human intervention.
For this reason, the time consuming gauge adjustment is
facilitated. However, a plurality of the swing levers 74 are
required for moving the back slides 72, and a plurality of
levers are also required for fastening and loosening the
fixing screws. In addition, the swing levers 74 and the
levers must be arranged at predetermined intervals in the
longitudinal direction of the base such that they do not
interfere with each other. This requires much space.
Furthermore, for moving the roller stand 78 in a similar
manner to the back slides 72, swing levers 74 and other levers
and driving mechanisms for driving them must be additionally
provided. Thus the structure is complicated, and a large
space is required.
-
With a structure which has a long back roller and a
plurality of back slides arranged at predetermined intervals,
as provided in a fine spinning machine, a back slide to which
a swing bar is coupled and a back slide provided with fixing
screws for fixing a roller stand can be arranged separately.
However, with a short back roller, as provided in drawing
machines, employment of the structure described above would
result in an excessively high proportion of space occupied by
the roller stand and the back slide to the space occupied by
the back roller.
-
In the apparatus 81 of Fig. 8, the connecting rods 86a,
86b are fixed to the base 85 by the clamp 88. With this
apparatus 81, therefore, it is not necessary to manipulate,
during adjustment of the gauge, the screw 87, which is
difficult to loosen and fasten. However, a plurality of screw
rods 91, equal to the number of connecting rods 86a, 86b, are
required. This increases costs. In addition, a large space
is required for installing the driving mechanism for
independently driving each pair of connecting rods 86a, 86b.
This increases the size of the apparatus.
BRIEF SUMMARY OF THE INVENTION
-
It is an object of the present invention to provide a
drafting apparatus for a spinning machine that is capable of
facilitating the gauge adjustment and is relatively small.
-
To achieve the above objective, the present invention
provides a drafting apparatus. The drafting apparatus
includes a drafting portion having a first, a second and a
third bottom rollers, which are positively rotated and
arranged from rearward to frontward in the running direction
of slivers. A pair of roller stands support the first, the
second and the third bottom rollers. A plurality top rollers
are arranged to cooperate with the bottom rollers. The top
rollers are pressed against the bottom rollers, respectively.
A fiber supplying portion is located rearward of the draft
portion for supplying the slivers to the drafting portion. A
pair first supporting members support the first bottom roller.
A pair of second supporting members support the second bottom
roller. A pair of third supporting members support the third
bottom roller. The first, the second and the third supporting
members are arranged in opposite order in the running
direction of the slivers. The second and the third supporting
members contact each other and are located on the roller
stands to move in a direction perpendicular to the axes of the
bottom rollers. A plurality of movable guide members are
perpendicular to the axes of the bottom rollers and are
supported by the first supporting member. A plurality of
fixed guide members have a plurality of first guide portions.
The first guide portions guide the movable guide members in a
direction perpendicular to the axes of the bottom rollers. A
plurality of fixing means fix the movable guide members to the
roller stands at locations that are rearward of the third
supporting members. driving means move the second supporting
members or the third supporting members with the movable guide
members.
-
Other aspects and advantages of the invention will
become apparent from the following description, taken in
conjunction with the accompanying drawings, illustrating by
way of example the principles of the invention.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
-
The present invention, together with objects and
advantages thereof, may best be understood by reference to the
following description of the presently preferred embodiments
together with the accompanying drawings in which:
- Fig. 1 is a partial side view of a drafting apparatus
according to a first embodiment of the present invention;
- Fig. 2 is a partial plan view of a drafting unit;
- Fig. 3(a) is a cross-sectional view illustrating a state
in which only a first pinion meshes with a corresponding rack;
- Fig. 3(b) is a cross-sectional view illustrating a state
in which first and second pinions mesh with corresponding
racks;
- Fig. 4 is a partial side view illustrating a driver for
bottom rollers;
- Fig. 5 is a plan view for explaining the action of the
drafting unit in Fig. 2;
- Fig. 6 is a cross-sectional view illustrating guide
portions in a second embodiment;
- Fig. 7 is a perspective view of a gauge adjusting
mechanism in the prior art; and
- Fig. 8 is a cross-sectional view of a drafting apparatus
in the prior art.
-
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
-
In the following, a first embodiment of a drafting
apparatus for a drawing machine will be described with
reference to Figs. 1 through 5. As illustrated in Fig. 1, a
drafting apparatus 1 includes a drafting unit 2, a fiber
feeder 3, a gatherer 4, a trumpet 5, and a pair of calendar
rollers 6a, 6b. The fiber feeder 3 is located upstream of the
drafting unit 2 (on the right side in Fig. 1). The gatherer 4
and the trumpet 5 are located downstream of the drafting unit
2. Both calendar rollers 6a, 6b are located downstream of the
trumpet 5. Below the calendar rollers 6a, 6b, a known coiler
wheel (coiler tube) 6c is located for guiding a sliver S
compressed by the calendar rollers 6a, 6b to a coiler can (not
shown). Assume that in Fig. 1, the right side is the rear and
the left side is the front.
-
The draft unit 2 includes a plurality (three in this
embodiment) of positively rotated first, second, third bottom
rollers 7a - 7c, and first, second, third top rollers 8a - 8c,
which correspond to the respective bottom rollers 7a - 7c.
The first, second, third top rollers 8a - 8c are pressed
against the first, second, third bottom rollers 7a - 7c,
respectively, by an urging mechanism (not shown). A cover 10
is supported for pivotal movement about a pivot shaft 9, which
is located behind the fiber feeder 3. The first, second,
third top rollers 8a - 8c are mounted in the cover 10.
-
The fiber feeder 3 is provided with a sliver guide 11
for imparting a tension of a predetermined value to a sliver S
being fed into the drafting unit 2. The sliver guide 11
includes a front section 12 located, which is near the
drafting unit 2, and a rear section 13, which is located
behind the front section 12. The rear section 13 is fixed at
a predetermined position on a base. The front section 12 is
supported by a supporting bracket, not shown, for movement
along a running direction of the sliver S, so that its
position is adjustable with respect to the running direction
of the sliver S. As illustrated in Fig. 4, the front section
12 is coupled to rear slides 20R, 20L through a coupling
member 14.
-
Each of the sections 12, 13 has a substantially U-shaped
cross section, and has a bottom plate 12a, 13a and a pair of
side plates 12b, 13b, respectively. The side plate 12b of the
front section 12 is positioned outside the side plate 13b of
the rear section 13, and the bottom plate 12a of the front
section 12 is positioned below the bottom plate 13a of the
rear section 13. The front section 12 is movable in this
state. Thus, the sliver guide 11 is telescopic.
-
The front section 12 of the sliver guide 11 is provided
with a plurality (two in this embodiment) of guide bars 15a,
15b that extend in the lateral direction and are vertically
adjustable. A pair of width restriction guides 15c is
positioned in front of the guide bar 15b. One guide bar 16 is
fixed at a predetermined position in the rear section 13.
-
As illustrated in Figs. 1 and 2, on a pair of roller
stands 17 fixed on a base frame 50, a first pair of movable
slides 18L, 18R are fixed at predetermined positions with
bolts (not shown). Behind the first slides 18L, 18R, a second
pair of movable slides 19L, 19R, and a third pair of movable
slides 20L, 20R are arranged.
-
Behind the third pair of slides 20L, 20R, fixed guide
members 21L, 21R are located at the rear end of the roller
stands 17. The bottom rollers 7a - 7c are rotatably supported
by the respective pairs of slides 18L, 18R; 19L, 19R; 20L, 20R.
A groove (not shown) is formed in the bottom of each of the
slides 18L - 20R. The groove engages an upper portion of the
roller stand 17 for positioning in the lateral direction.
-
Fixed to each of the slides 19L, 19R, 20L, 20R are a
pair of outer rods 22L, 22R and a pair of inner rods 23L, 23R,
respectively, which are perpendicular to the respective bottom
rollers 7a - 7c.
-
Each of the outer rods 22L, 22R extends through fitting
holes 24 formed through each of the slides 19L, 19R of the
second pair, and each is fixed to one of the slides 19L or 19R
of the second pair with a bolt (not shown). Each of the inner
rods 23L, 23R extends through fitting holes 25 formed through
each of the third slides 20L, 20R, and each is fixed to one of
the slides 20L or 20R of the third pair with a bolt (not
shown).
-
The first pair of slides 18L, 18R has front guide
portions 26, which engage with the outer rods 22L, 22R and the
inner rods 23L, 23R to guide them in a direction perpendicular
to the first, second, third bottom rollers 7a - 7c. The pair
of fixed guide members 21L, 21R is provided with rear guide
portions 27, which engage with the respective outer rods 22L,
22R and the respective inner rods 23L, 23R to guide them in
the direction perpendicular to the first, second, third bottom
rollers 7a - 7c. The rear guide portions 27 are opposite to
the respective front guide portions 26. Both guide portions
26, 27 have through holes in which a liner (metal bushing) is
fitted. Each of the outer rods 22L, 22R and each of the inner
rods 23L, 23R is in engagement with both guide portions 26, 27
at all times.
-
Each of the slides 19L, 19R of the second pair is
provided with a first intermediate guide portion 28 for
allowing the inner rods 23L, 23R to slide horizontally. The
slides 20L, 20R of the third pair are provided with second
intermediate guide portions 29 for allowing the outer rods 22L,
22R to slide horizontally state. Each of the guide portions
28, 29 is provided with a through hole in which a liner is
fitted.
-
Behind the fixed guide members 21L, 21R, stop brackets
30L, 30R, 31L, 31R are arranged in correspondence with the
outer rods 22L, 22R and the inner rods 23L, 23R. Each stop
brackets 30L, 30R, 31L, 31R has a through hole corresponding
to the guide portions 27. The outer rods 22L, 22R and the
inner rods 23L, 23R pass through the respective through holes,
and are fastened with bolts 32, thereby fixing the outer rods
22L, 22R and the inner rods 23L, 23R to prevent their movement
relative to the roller stand 17. In this embodiment, the
respective stop brackets 30L, 30R, 31L, 31R and the bolts 32
constitute fixing means.
-
On the top surface of each of the outer rods 22L, 22R,
each of the racks 33L, 33R is positioned in front of the stop
bracket 30L or 30R with each of the second slides 19L, 19R
placed at the rearmost position. Behind the fixed guide
members 21L, 21R, a pair of supporting brackets 34L, 34R are
located. Between the supporting brackets 34L, 34R, an
adjusting shaft 35 is supported. The adjusting shaft 35 is
perpendicular to the rods 22L, 22R and extends laterally for a
greater distance than the top rollers 8a - 8c by a
predetermined value.
-
The adjusting shaft 35 has two pinions 36L, 36R, which
mesh with the racks 33L, 33R, respectively. The first pinion
36R is longer axially than the second pinion 36L. The
adjusting shaft 35 is located such that it can be adjusted to
a first position, at which both pinions 36L, 36R mesh with the
corresponding racks 33L, 33R, and a second position, at which
only the first pinion 36R meshes with the first rack 33R. In
this embodiment, the axial length of the second pinion 36L is
substantially one half that of the first pinion 36R.
-
As illustrated in Fig. 1, the adjusting shaft 35 has a
fitting portion 35a at an end. A handle 37 is fitted to the
fitting portion 35a for rotating the adjusting shaft 35. In
this embodiment, both racks 33L, 33R, both pinions 36L, 36R,
the adjusting shaft 35 and handle 37 constitute a driving
mechanism for integrally moving the pair of outer rods 22L,
22R longitudinally.
-
As illustrated in Fig. 4, a pulley 38 is fixed to the
third bottom roller 7c outside of the right third slide 20R.
The third bottom roller 7c is driven through a belt 41 wrapped
around a pulley 38, a guide pulley 39, a tension pulley 40 and
a driving pulley (not shown). The rotation of the third
bottom roller 7c is transmitted to the second bottom roller 7b
through a gear (not shown). Outside the right first slide 18R,
a pulley 42 is fixed to the first bottom roller 7a. The first
bottom roller 7a is driven through a belt 45 wrapped around a
pulley 42, a guide pulley 43, a tension pulley 44, and a
driving pulley (not shown).
-
Next, operation of the action of the apparatus
constructed as described above will be described. As
illustrated in Fig. 1, a plurality of slivers S drawn from a
plurality of feed coiler cans (not shown) located behind the
drafting apparatus 1 are combined into a bundle of fibers
having a predetermined width by the guide bars 16, 15a, 15b
and the width restriction guide 15c and are fed into the
drafting unit 2. The bundle of fibers fed into the drafting
unit 2 sequentially passes between the first, second, third
bottom rollers 7a - 7c and the first, second, third top
rollers 8a - 8c and is thereby extended at a predetermined
drafting ratio. The bundle is spun from the drafting unit 2
and transformed into a fleece F. The fleece F spun from the
drafting unit 2 is converged into a sliver S by the gatherer 4
and the trumpet 5. The sliver S is compressed by the calendar
rollers 6a, 6b, and accommodated in the coiler can through the
coiler tube 6c.
-
Next, a method of adjusting the gauge of each of the
bottom rollers 7a - 7c will be described. As illustrated in
Fig. 4, first, the tension pulley 40 for imparting tension to
the belt 41 for driving the second and third bottom rollers 7b,
7c is moved to loosen the tension in the belt 41. Next, the
respective bolts that fix the outer rods 22L, 22R and the
inner rods 23L, 23R to the respective stop brackets 30L, 30R,
31L, 31R are loosened.
-
Next, the handle 37 is fitted into the fitting portion
35a of the adjusting shaft 35, and the handle 37 is pushed
toward the supporting bracket 34R. This causes the adjusting
shaft 35 to move until the first pinion 36R abuts against the
supporting bracket 34R, as illustrated in Figs. 2 and 3(b).
In this state, the pinions 36L, 36R mesh with the outer rods
22L, 22R, respectively. As the handle 37 is rotated in the
counter-clockwise direction in Fig. 1, both racks 33L, 33R,
with which the pinions 36L, 36R mesh, are moved rearward.
This causes the second pair of slides 19L, 19R to move
rearward together.
-
As the second pair of slides 19L, 19R moves rearward,
the second pair of slides 19L, 19R and the third pair of
slides 20L, 20R are moved rearward together after the second
slides 19L, 19R abut against the third slides 20L, 20R. When
the slides 20L, 20R of the third pair are moved to holding
positions on the roller stand 17 of the third slides 20L, 20R,
which have been previously determined based on the length of
fibers to be spun, the bolts 32 of the pair of stop brackets
31L, 31R are fastened to fix the third slides 20L, 20R at the
predetermined positions. As the front section 12 is moved
together with the slides 20L, 20R of the third pair, and as
the third slides 20L, 20R are placed at predetermined
positions, the front section 12 is also fixed at a
predetermined position, which has been determined after the
gauge adjustment.
-
As illustrated in Fig. 5, after the slides 20L, 20R of
the third pair have been fixed at the predetermined positions
on the roller stand 17, the handle 37 is rotated in the
clockwise direction in Fig. 1 to reverse the adjusting shaft
35, which causes the pair of second slides 19L, 19R to move
frontward. When the slides 19L, 19R of the second pair are
moved to fixed positions previously determined based on the
length of fibers, the rotation of the handle 37 is stopped and
the bolts 32 of the stop brackets 30L, 30R are fastened. As a
result, the second slides 19L, 19R are fixed at the
predetermined positions.
-
In moving the respective slides 19L, 19R, 20L, 20R
through the pinions 36L, 36R and the racks 33L, 33R with the
rotation of the adjusting shaft 35, the amounts of movement
may differ between the respective slides 19L, 19R, 20L, 20R
due to such causes as friction resistance, backlash and so on.
In such an event, the left-hand third slide 20L is first moved
to a predetermined position with the adjusting shaft 35 placed
at the first position, at which both pinions 36L, 36R mesh
with the racks 33L, 33R, and then the inner rod 23L is fixed
with the bolt 32.
-
Next, as illustrated in Fig. 3(a), the adjusting shaft
35 is placed at the second position, at which only the first
pinion 36R meshes with the first rack 33R. The adjusting
shaft 35 is rotated to finely adjust the position of the
right-hand third slide 20R. If the right-hand third slide 20R
is located behind the left-hand third slide 20L when the left-hand
third slide 20L is fixed at the predetermined position,
the handle 37 is rotated in the counter-clockwise direction to
move the right-hand third slide 20R rearward together with the
right-hand second slide 19R.
-
When the right-hand third slide 20R is placed behind the
left-hand third slide 20L, the handle 37 is rotated in the
clockwise direction to move the right-hand second slide 19R
forward, and the inner rod 23R is pushed by hand to move the
right-hand third slide 20R forward of the position of the
left-hand third slide 20L. Next, the handle 37 is rotated in
the counter-clockwise direction to move the right-hand third
slide 20R rearward, together with the right-hand second slide
19R, to a predetermined position, at which they are stopped,
and the bolt 32 of the inner rod 23R is fastened to fix the
right-hand third slide 20R. Thus, alignment of the left and
right third slides 20L, 20R is completed.
-
Next, the adjusting shaft 35 is pressed again to the
first position, at which the pinions 36L, 36R mesh with the
racks 33L, 33R, respectively. In this state, the handle 37 is
rotated in the clockwise direction to move both of the second
slides 19L, 19R forward, and the rotation of the handle 37 is
stopped when the left-hand second slide 19L is moved to a
predetermined position. Then, the bolt 32 for the outer rod
22L is fastened to fix the left-hand second slide 19L. Next,
the adjusting shaft 35 is placed at the second position, and
the handle 37 is rotated either to the left or to the right to
move the second slide 19R to a predetermined position. Next,
the bolt 32 for the right-hand second rod 22R is fastened to
fix the right-hand second slide 19R. Thus, the gauge
adjustment between the draft rollers is completed.
Subsequently, the handle 37 is removed, and the tension pulley
40 is placed at a predetermined position.
-
This embodiment provides the following advantages.
-
The outer rods 22L, 22R and the inner rods 23L, 23R are
fixed to the roller stand 17 at locations that are rearward of
the third slides 20L, 20R through the bolts 32 and the stop
brackets 30L, 30R, 31L, 31R, such that outer rods 22L, 22R and
the inner rods 23L, 23R cannot be moved relative to each other.
Thus, at a position apart from the second slides 19L, 19R and
the third slides 20L, 20R and therefore at a position where
the operation is facilitated, the bolts 32 are fastened to fix
the outer rods 22L, 22R and the inner rods 23L, 23R to the
roller stand 17.
-
The outer rods 22L, 22R that are fixed to the second
slides 19L, 19R are integrally moved rearward through both
pinions 36L, 36R and both racks 33L, 33R with the rotation of
the adjusting shaft 35. In the rearward movement, the slides
20L, 20R of the third pair are moved simultaneously with the
second slides 19L, 19R. Therefore, the driving mechanism
dedicated to the third slides 20L, 20R can be eliminated,
thereby making it possible to reduce the size of the apparatus.
-
The outer rods 22L, 22R and the inner rods 23L, 23R are
fixed to second slides 19L, 19R and the third slides 20L, 20R
and extend through the second slides 19L, 19R and the third
slides 20L, 20R, respectively. Further, the respective rods
22L, 22R, 23L, 23R are always in engagement with the guide
portions 26 formed on the first slides 18L, 18R, and the outer
rods 22L, 22R are guided by the second intermediate guide
portions 29 of the third slides 20L, 20R, while the inner rods
23L, 23R are guided by the first intermediate guide portions
28 of the second slides 19L, 19R. Therefore, the second
slides 19L, 19R and the third slides 20L, 20R are each moved
in a stable state.
-
The pinions 36L, 36R, which mesh with the racks 33L, 33R,
respectively, are integrally fixed to the adjusting shaft 35,
which is perpendicular to the outer rods 22L, 22R. It is
therefore possible to integrally move both outer rods 22L, 22R
with a simple construction.
-
The adjusting shaft 35 is movable to the first position,
at which the pinions 36L, 36R can mesh with the racks 33L, 33R,
respectively, and to the second position, at which only the
first pinion 36R can mesh with the first rack 33R. Therefore,
the right-hand second slide 19R and the right-hand third slide
20R can be moved with the rotation of the adjusting shaft 35
without moving the left-hand second slide 19L and the left-hand
third slide 20L. As a result, the alignment operation
can be carried out for the pair of second slides 19L, 19R and
the pair of third slides 20L, 20R.
-
The sliver guide 11 located in the fiber feeder 3 is
divided into the front section 12 and the rear section 13, and
the front section 12 is adjustable in relative to the running
direction of the sliver S. Therefore, the sliver guide 11 can
be placed at a position suitable for spinning conditions even
if the positions of the third slides 20L, 20R are changed due
to a gauge adjustment.
-
The front section 12 of the sliver guide 11 is coupled
to the third slides 20L, 20R through the coupling member 14.
Therefore, the front section 12 is automatically brought to a
proper position with the movement of the third slides 20L, 20R.
-
The adjusting shaft 35 is rotated by the handle 37.
This eliminates the need for providing a driving source such
as a motor, an engine or the like, thereby achieving a simple
and compact construction.
-
The foregoing embodiment may be modified, for example,
in the following manner.
-
A plurality of pinions having a narrow tooth width may
be provided to constitute the first pinion 36R to increase a
region, as a whole, for meshing with the first rack 33R.
-
Thus, any of the pinions having a small axial dimension,
may mesh with the first rack 33R whether the adjusting shaft
35 is at the first position or at the second position.
-
It may be determined from the lengths of the outer rods
22L, 22R and the inner rods 23L, 23R protruding from the fixed
guide members 21L, 21R how far the second slides 19L, 19R and
the third slides 20L, 20R are from the positions of the first
slides 18L, 18R, which serve as references. Therefore, the
positioning is facilitated as compared with the case where the
positions of the second slides 19L, 19R and the third slides
20L, 20R are registered to marks impressed on the roller stand
17 in line with the respective slides.
-
The handle 37 may be fixed to the adjusting shaft 35 so
that it cannot be removed.
-
The guide portions 26, 27 are not limited to holes but
may be grooves, as illustrated in Fig. 6. Also, the first and
second intermediate guide portions 28, 29 may also be formed
in similar grooves.
-
The pinions 36L, 36R may be formed to have the same
axial dimension such that the outer rods 22L, 22R cannot be
individually moved. In this event, if the racks 33L, 33R and
the pinions 36L, 36R of the outer rods 22L, 22R are accurately
formed to reduce backlash and accuracy, the alignment need not
be performed for the left-hand and right-hand second slides
19L, 19R and third slides 20L, 20R each time the gauge is
adjusted.
-
The adjusting shaft 35 for integrally driving the outer
rods 22L, 22R may be driven by a driving source such as a
motor. For example, a motor is used as a driving source, and
a rotary encoder is provided for detecting the amount of
rotation of the motor. In this variation, the amounts of
movement of the second slides 19L, 19R and the third slides
20L, 20R can be found from the amount of rotation of the motor.
By stopping the motor when it has been moved over a
predetermined amount, the second slides 19L, 19R and the third
slides 20L, 20R can be moved to desired positions.
-
As the driving mechanism for moving the pair of outer
rods 22L, 22R integrally in the longitudinal direction, a
screw shaft may be used in place of the rack and pinion, as in
the apparatus illustrated in Fig. 8. For example, blocks are
fixed to the outer rods 22L, 22R, respectively, and the each
of the blocks is formed with a threaded hole, and a screw
shaft is provided for screw engagement with the threaded hole.
Both screw shafts are simultaneously driven through a belt
driving mechanism. The belt driving mechanism may be driven
manually or using a driving source such as a motor.
-
As a structure for simultaneously moving the second
slides 19L, 19R and the third slides 20L, 20R, the inner rods
23L, 23R may be provided with racks. Then, the adjusting
shaft 35 is rotated while the racks mesh with pinions located
on the adjusting shaft 35 to move the inner rods 23L, 23R.
During a gauge adjustment, the adjusting shaft 35 is rotated
from a state in which the second slides 19L, 19R and the third
slides 20L, 20R are placed behind the desired positions, to
move the second slides 19L, 19R forward together with the
third slides 20L, 20R. Then, after the second slides 19L, 19R
are moved to the desired positions and fixed there by
fastening the bolts 32, the adjusting shaft 35 is rotated in
the reverse direction to move the third slides 20L, 20R to the
desired positions, at which they are fixed.
-
The present invention may be applied to a drafting
apparatus that has four or more bottom rollers. For example,
with four bottom rollers, back roller slides may be provided
behind the third slides 20L, 20R. Likewise, the back roller
slides can be moved perpendicular to the bottom rollers and
fixed to the roller stand 17. During a gauge adjustment, the
third slides 20L, 20R and the back slides are moved rearward
together with the second slides 19L, 19R to fix the back
slides at predetermined positions. Next, the second slides
19L, 19R and the third slides 20L, 20R are moved forward, and
the third slides 20L, 20R and the second slides 19L, 19R are
fixed at predetermined positions from that state in a similar
manner. In this event, the back slides may be provided with
movement guide members as is the case of the foregoing
embodiment.
-
The rods 22L, 22R, 23L, 23R may be directly fixed to the
fixed guide members 21L, 21R, respectively, with the bolts 32.
In this case, the structure becomes simpler.
-
As the movement guide member, a plate-like member may be
used in place of the rods.
-
The drafting apparatus 1 is not limited to a drafting
apparatus for a drawing machine but may be applied to other
spinning machines which comprise a fiber feeder for supplying
the sliver S to the drafting unit, for example, a sliver lap
machine and a comber. Also, the drafting apparatus 1 may be
applied to a drafting apparatus for a fine spinning machine
and a roving frame.
-
It should be apparent to those skilled in the art that
the present invention may be embodied in many other specific
forms without departing from the spirit or scope of the
invention. Particularly, it should be understood that the
invention may be embodied in the following forms.
-
Therefore, the present examples and embodiments are to
be considered as illustrative and not restrictive and the
invention is not to be limited to the details given herein,
but may be modified within the scope and equivalence of the
appended claims.
A drafting apparatus includes a pair of first slides, a pair
of second slides, and a pair of third slides. The draft
apparatus includes a pair of roller stands. A pair of outer
rods are fixed to the second slides. A pair of inner rods are
fixed to the third slides. An adjusting shaft has pinions.
Racks are formed on the outer rods. The racks mesh with the
pinions. The outer and inner rods are fixed to the roller
stands at locations that are rearward of the third slides.
When the adjusting shaft is rotated, the outer rods move
simultaneously. This is capable of facilitating the gauge
adjustment and of making adjustment device relatively small.