JPH07122173B2 - Draft device in spinning machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a bottom roller arranged between the largest draft portions of a draft according to the characteristics of fibers to be spun such as short fibers and long fibers. The present invention relates to a drafting device for a spinning machine, which can easily change the position where the pressure bar is arranged so that the switching operation of the drafting device with respect to changes in fiber characteristics such as fiber length can be performed quickly.

[Conventional technology]

For example, a four-wire type draft device is composed of four pairs of rollers 1,2,3,4 composed of a bottom roller and a top roller, as shown in FIG. 7 and FIG. 1 to 4 are attached to roller slides 5, 6, 7, and 8, respectively. The bottom roller and the top roller forming the roller pair will be described by adding the suffixes "a" and "b" to the reference numerals of the roller pair, respectively.

The bottom roller is driven to rotate, and the top roller is driven to rotate.

An end bracket 9 is fixed to the upper end surface of the second roller slide 6 via a tightening bolt 11, and both ends of the second top roller 2b are supported by the end bracket 9. The pressure bar holders 12a and 12b (however, 12b is not shown in FIG. 8) are attached to both ends of the second top roller 2b which constitutes the second roller pair 2, respectively. Both ends of the pressure bar 13 are supported by 12a and 12b, and the pressure bar 13 is
It is arranged between the front roller pair 1 and the second roller pair 2.

The arrangement of the roller pairs 1 to 4 shown in FIG. 7 is for spinning short fibers. In this roller pair arrangement state, when spinning a long fiber having a fiber length of 60 mm or more, a bias cut fiber, a mixed fiber of a short fiber and a long fiber, or an animal / vegetable fiber, a compound fiber, etc. As shown in the figure, the third roller pair 3 is removed, and the roller slide 6 to which the second roller pair 2 is attached is re-fixed on the upstream side, and a gauge ( It was set by setting the dimension between rollers). For this reason, there are the following problems.

(1) When the gauge is set in accordance with the long fibers, the second bottom roller 2a and the pressure bar 13 are too close to each other because the position of the pressure bar 13 in the largest draft portion of the draft is not appropriate.
Since the distance between the pressure bar 13 and the front bottom roller 1a was too wide, the short fibers could not be regulated in the draft section that drew a large draft, resulting in an illegal draft and uneven weight distribution of the sliver.

That is, in the case of blending short fibers and long fibers, or blending synthetic fibers and animal and vegetable fibers (hereinafter collectively referred to as blended fibers), and further when spinning bias cut fibers, the length of the short fibers is Since the distance between the bar 13 and the front bottom roller 1a is shorter, some short fibers are subordinate to the downstream fiber group F and some are subordinate to the upstream fiber group F. Becomes unstable.

In addition, short fibers may fall off from the flow of the fiber group F, which causes weight unevenness in the spun sliver and deteriorates its quality. In particular, in the mixed spinning of synthetic fibers and animal and vegetable fibers, the friction resistance of each other,
Since the characteristics such as crimp and fiber length are different, they are in a state of being easily separated, and the mutual restraining force is small or has disappeared.Therefore, they often fall out of the regular fleece flow between rollers. .

(2) As described above, the third roller pair 3 is attached and detached, and the roller slide 6 to which the second roller pair 2 is attached is moved to cope with the change in fiber length. From fibers to short fibers, even mixed spinning and bias cut fibers,
Can not be widely supported.

(3) Each time the fiber length or the type of fiber changes, the third roller pair 3 is attached and removed, and the second roller pair 2 is attached to the roller slide 6.
However, since it has been moved, it takes a lot of time for this switching work, resulting in a decrease in production efficiency. In particular, with the recent diversification of needs, the number of times of switching the draft device has increased, and the switching time cannot be ignored.

[Problems to be Solved by the Invention]

The present invention, in view of the drawbacks of the conventional drafting device as described above, simplifies the switching operation of the drafting device with respect to changes in fiber characteristics such as fiber length, and at the same time, from short fibers to long fibers, further The object was to make it possible to handle a wide range of fibers, including blended fibers and bias cut fibers, and to produce high quality sliver.

[Means for Solving the Problems]

Means adopted by the present invention to solve the above problems, among the draft portion composed of two pairs of front and rear roller pairs, which is a set of a bottom roller and a top roller, of the draft portion having the largest draft rate. A bottom roller that is driven to rotate is provided near the center or on the upstream side of the center, and a pressure bar is provided near the bottom roller so that it can be arranged on both the upstream side and the downstream side. At the time of spinning, the pressure bar is arranged on the upstream side of the bottom roller, and at the time of spinning short fibers,
The pressure bar is arranged on the downstream side of the bottom roller, and the top roller is mounted above the bottom roller so that each fiber is spun.

[Operation of the invention]

When spinning long fibers or blended fabrics, a pressure bar is arranged upstream of the bottom roller arranged in the draft section with the largest draft ratio, and a top roller is provided above this bottom roller. Not not. Therefore, the distance between the nip points of the fiber group in the draft section becomes long. Between the two pairs of front and rear rollers forming the draft part, the fiber group is not completely gripped, but the drafted fiber group is strongly pressed against the pressure bar and the bottom roller. , The pressed portion serves as a virtual nip point that acts close to the nip point.

Therefore, the frictional resistance between the fibers is increased, and the fibers are restrained from each other, so that the short fibers are appropriately drafted without being driven by the long fibers, and at the same time, the bottom roller and the pressure bar are Since the fiber group is not surely gripped in the part (1), the long fiber is strongly pulled by the lower roller pair and appropriately drafted without being cut.

On the other hand, when drafting short fibers, a pressure bar is arranged on the downstream side of the bottom roller, and by mounting a top roller above this bottom roller, the fiber group in the draft part with the largest draft rate Shorten the distance between nip points and set each gauge to the fiber length for drafting.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to examples.
Note that the same parts as those described in the section “Prior Art” are given the same reference numerals and described.

1 to 3 show long fibers, blends,
In a state of drafting the bias cut fibers, the end bracket 9 is movable on the upper end surface of the second roller slide 6 in the front-rear direction and is fixed at a predetermined position via a tightening bolt 11. A guide portion 9a is provided inside the end bracket 9, and both end portions of the holder rod 14 are immovable in the front-rear direction but not in the front-rear direction with respect to the guide portion 9a of the end bracket 9. Is supported as. Holder rod 14
In the state in which the holder rod 14 is supported by the guide portion 9a of the end bracket 9, the holder rod 14 is arranged immediately above or almost directly above the second bottom roller 2a, but is not in contact with the second bottom roller 2a. At both ends of this holder rod 14, pressure bar holders 12a, 12b
Are rotatably mounted about the axis of the holder rod 14.

Both ends of the pressure bar 13 have a smaller diameter than the other portions, and the small diameter portion 13a is fitted into the fitting hole 15 provided in the pressure bar holders 12a and 12b, and the holder 12a, It protrudes from the outer surface of 12b,
It is in contact with a guide portion 6a provided on the second roller slide 6. A spring seat 16 is provided on the upper surfaces of the pressure bar holders 12a and 12b, and the restoring force of a spring (not shown) elastically contacting the spring seat 16 urges the pressure bar 13 downward. There is. When the end bracket 9 is moved in the front-rear direction, the pressure bar 13 is moved in the same direction along the guide portion 6a. In FIGS. 1 to 3, P indicates the flowing direction of the fiber group F.

As shown in FIGS. 1 to 3, when drafting long fibers, blended fibers, and bias cut fibers, the pressure bar 13 is arranged upstream of the second bottom roller 2a and The second top roller 2b is not mounted above the second bottom roller 2a.

In this state, when the fiber group F flows between the roller pairs 1, 3, and 4, the fiber group F is drafted 1.2 to 2 times between the back roller pair 4 and the third roller pair 3. Then, in the draft portion having the largest draft rate between the third roller pair 3 and the front roller pair 1, the draft is drafted about 4 to 7 times. In the largest draft part of the draft, the bottom part of the pressure bar 13 is the third bottom roller 3a and the second bottom roller.
Since the fiber group F is located below the tangent line of each upper part of 2a, the fiber group F is strongly pressed down by the pressure bar 13, passes over the second bottom roller 2a, and is strongly pressed by the front roller pair 1. Pulled
It will be largely drafted. Here, between the third roller pair 3 and the front roller pair 1, the fiber group F is not completely gripped by the bottom roller and the top roller, but the pressure bar 13 is in the positional relationship as described above. Since the fiber group F is largely drafted, the fiber group F becomes a second bottom roller.
Partially squeezed between A ₁ and A ₂ at the top of 2a and B ₁ and B ₂ at the bottom of the pressure bar 13 (these are called virtual nip points) Since the frictional resistance between the fibers is increased, the fibers are bound to each other, and the state is substantially close to the state in which the fibers are gripped by the bottom roller and the top roller. Therefore, the short fibers included in the fiber group F are appropriately drafted without being driven by the long fiber group, and the phenomenon that the short fibers fall off from the fiber group F does not occur. In addition, between the third roller pair 3 and the front roller pair 1, the long fibers are
13 and each virtual nip point of the second bottom roller 2a is not reliably gripped, and is therefore appropriately drafted by being strongly pulled by the front roller pair 1 without being cut.

When drafting long fibers, blended fibers, or bias cut fibers, by appropriately moving the second roller slide 6 or the third roller slide 7 in accordance with the fiber length, the nip point in the largest draft portion of the draft can be obtained. You can adjust the distance and draft properly.

On the other hand, when drafting short fibers,
As shown in the figure, the pressure bar holders 12a and 12b, which were fitted to the left and right ends of the holder rod 14, are flipped to the left and right, and fitted into both ends of the second top roller 2b, and both ends of the second top roller 2b are fitted. When supported by the guide portion 9a of the end bracket 9, the second top roller is located above the second bottom roller 2a.
2b is installed. This way, the pressure bar
13 is arranged on the downstream side of the second bottom roller 2a, and the distance between the nip points in the draft portion having the largest draft rate formed by the front roller pair 1 and the second roller pair 2 becomes short. Then, each gauge is set according to the fiber length of the short fibers to be spun, and drafting is performed.

As described above, since the draft device can be switched from the long fiber to the short fiber or vice versa without removing the third roller pair 3, the draft device can be switched in a short time. By moving the third roller pair 3, the second bottom roller 2a, and the pressure bar 13, the optimum gauge setting can be performed in accordance with a wide range of fiber characteristics such as fiber length.

In another embodiment shown in FIG. 6, the pressure bar holder 12a (12b) is integrally formed with the end bracket 9 '. By doing so, the holder rod 14 is not arranged above the second bottom roller 2a, so that problems such as the accumulation of cotton wool on the holder rod 14 are eliminated. However, when spinning short fibers, it is necessary to replace the entire end bracket 9 '.

〔The invention's effect〕

According to the draft device of the present invention, it is possible to easily switch the draft device from the long fiber to the short fiber or vice versa without removing a specific roller pair, so that the draft device can be switched in a short time. Can be done at.

Also, without removing the roller pair, by attaching and removing the top roller of a specific roller pair and changing the arrangement position of the pressure bar, various fibers having different fiber characteristics such as fiber length are spun. Therefore, it is possible to set the optimum gauge according to a wide range of fiber characteristics. Therefore, a wide range of fibers such as blended fibers and bias cut fibers can be handled, and a high quality sliver can be spun out.

[Brief description of drawings]

FIGS. 1 to 6 are views for explaining the present invention. FIG. 1 shows each roller pair 1, 3, 4 and pressure bar 13 of a drafting device when spinning long fibers. 2 is an enlarged view of the portion of the pressure bar 13 in FIG. 1, FIG. 3 is a perspective view of the portion of the pressure bar 13 in FIG. 1 seen from the rear, and FIG.
Figure, schematic side view showing the arrangement of each roller pair 1 to 4 of the draft device and the pressure bar 13 when spinning short fibers, and Figure 5 is a rear view of the portion of the pressure bar 13 in Figure 4. FIG. 6 is a perspective view showing the pressure bar holder 12 integrally provided on the end bracket 9 ′.
It is a perspective view of the portion of the pressure bar 13 supported by a and 12b. 7 to 9 are views for explaining a conventional drafting device, FIG. 7 is a perspective view of the drafting device when spinning short fibers, and FIG. 8 is also an end bracket. FIG. 9 is a plan view of the portion 9 and FIG. 9 is a schematic side view showing the arrangement of each roller pair when spinning a long fiber. The explanation of the reference numerals of the main parts constituting the present invention is as follows. 1-4: Roller pair 1a-4a: Bottom roller 1b-4b: Top roller 9: End bracket 12a, 12b: Pressure bar holder 13: Pressure bar, 14: Holder rod

Claims (1)

[Claims] 1. A draft part composed of two pairs of front and rear roller pairs, one set consisting of a bottom roller and a top roller, near the center of the draft part having the largest draft rate, or on the upstream side of the center. , A bottom roller that is driven to rotate is provided, and a pressure bar is provided in the vicinity of the bottom roller so that it can be arranged on both the upstream side and the downstream side of the bottom roller. The pressure bar is arranged on the upstream side of the above, and when the short fibers are spun, the pressure bar is arranged on the downstream side of the bottom roller, and a top roller is mounted above the bottom roller to spin each fiber. A drafting device for a spinning machine, which is configured to be ejected.