JP7391763B2 - A focusing device for a spinning machine, a draft device with a focusing device, and a method for operating a focusing device - Google Patents

Description

The invention relates to a focusing device for a spinning machine, in particular a ring spinning machine, for bundling drafted sliver, which comprises a focusing unit, the focusing unit comprising a suction air supply arranged in a base body. and a suction opening to which suction air is supplied from a suction air supply, over which a focusing apron is replaceably arranged.

Drafting devices for spinning machines are known from the prior art in a wide variety of configurations. The drafting device serves to draft or draw the sliver, thereby reducing the fiber cross section. During drawing, the fibers must then be moved alongside each other as evenly as possible in order to obtain a uniform sliver, and the uniform sliver thus obtained must be moved in order to produce a uniform yarn. This is a prerequisite.

Spinning machines in which the twisting takes place directly downstream of the drafting device have the disadvantage that a so-called spinning triangle is formed at the exit roller pair of the drafting device. This spinning triangle has edge fibers which are clearly wider than the developing yarn and which are not neatly bonded to the developing yarn. Such edge fibers therefore contribute little to the strength of the yarn to be spun.

In order to avoid spinning triangles, it is already known from the prior art to arrange a focusing device downstream of the drafting device, in which the drafted but still largely untwisted sliver is is focused or bundled by having its fibers gathered at the sides. The avoidance of spinning triangles during twisting results in twisted yarns that are more uniform, have higher tensile strength, and have less fuzz.

Such focusing devices are used in particular in ring spinning machines. In ring spinning machines, the twist is provided by a rotating ring spinning spindle and a ring traveler rotating along the spinning ring.

Known focusing devices are usually configured to operate pneumatically. In this case, it is already known that the sliver is brought together by suction into perforation tracks extending along the fiber running direction, through which air is sucked in using a suction air stream. The perforation track then extends in the transport direction of the focusing apron, which is arranged to circulate around the suction opening. Such a focusing system with a perforated apron along the suction track is known, for example, from DE 43 23 472 A1. In an alternative configuration in which the focusing apron is made of a narrow woven fabric, the suction opening is designed as a narrow slit, through which only the suction airflow acts on the sliver and focuses it. do. Such a focusing system is disclosed in DE 198 46 268 A1.

The focusing device has a base body with a suction air supply. The base body can be designed as an apron cage surrounded by a focusing apron. Furthermore, the apron cage can be configured in such a way that the apron cage can accommodate the supply roller and the focusing apron surrounds the apron cage and the supply roller. The part of the base body surrounded by the focusing apron can then be designed as a suction shoe with a suction air supply. Preferably, the base body is designed such that the focusing device includes two focusing units for one spinning unit in each case. The focusing apron is subjected to forced wear due to the guidance of the fibers and is therefore usually arranged in a replaceable manner.

The base body may be designed as a hollow profile, which extends in the longitudinal direction of the machine and includes a suction air supply in the area of the spinning unit in the circumferential direction. The hollow profile may extend over several spinning units, that is to say over two or more spinning units or over the entire spinning machine. The hollow profile is preferably splittable, so that the focusing apron can be replaced if necessary.

The use of focusing aprons with perforation tracks, and the use of focusing aprons formed from narrow-knit woven fabrics, has advantages and disadvantages in relation to the fibers to be treated. The use of such aprons therefore requires modification of known focusing devices, in particular draft devices equipped with focusing devices, only at considerable cost after the selection made on the part of the customer for the focusing system. The disadvantage is that once a decision has been made, one must always accept the shortcomings that occur in the selected system.

Furthermore, the disadvantage of known drafting devices with focusing devices is that, if in some cases no focusing is desired, this desire cannot be easily achieved by stopping the suction of the focusing device. This is because when the suction is stopped, the fibers are no longer guided in the area that was previously acting as a focusing area. In some cases, this can lead to fiber damming and yarn breakage upstream of conventional focusing devices.

Starting from the prior art mentioned above, the problem underlying the invention is to provide a focusing device and a draft device equipped with a focusing device, in which the focusing system can be easily replaced.

This problem is solved by a focusing device, in which the focusing unit includes a cover with a cover opening for covering the suction air supply. According to the invention, the base body is designed to releasably accommodate a cover covering the suction air supply, and the suction opening for actuating the focusing unit is variable with the help of the cover.

Within the scope of the invention, a focusing system is understood to mean an arrangement of a focusing unit for focusing the fiber sliver. The focusing systems known at this time include, on the one hand, the construction of a focusing unit by a combination of a focusing apron with an open suction opening and a perforation track, and, on the other hand, a focusing apron formed from a breathable woven fabric; and the configuration of a focusing unit in combination with a suction opening narrowed by a slit.

The invention is distinguished here by at least the simple exchange between these two systems. An important feature of the focusing device according to the invention then lies in the design of the base body, which is designed to accommodate a cover in the area of the suction air supply, so that the focusing device can be used with the help of the cover. The suction opening for operating the unit can be varied. If desired, the suction opening can be limited to a narrow slit, through which only the suction air flow acts on the sliver and causes focusing. According to the invention, the suction opening can be increased by means of a cover such that the suction opening is used in conjunction with a focusing apron having perforation tracks, in which the suction airflow flows through the perforation tracks of the focusing apron. restricted through. If necessary, the focusing unit of the focusing device can be easily modified due to the fact that the cover can be releasably arranged on the base body and that different focusing aprons can be arranged on the base body, so that this The focusing device then performs focusing via a suction slit and a focusing apron formed from a woven fabric.

The focusing device according to the invention can therefore be operated by the user in an optimal manner for the respective intended use, so that the sliver in the area of the focusing device is brought together reliably and optimally. Furthermore, the focusing device according to the invention can also be operated in such a way that no focusing takes place. Therefore, a spinning machine equipped with a converging device according to the invention or a drafting device according to the invention can also be used in a spinning machine, in particular a ring spinning machine, even if it is desired to produce conventional ring yarns instead of compact yarns. It can be operated in In order to avoid focusing, the focusing device according to the invention is operated with an increased suction opening and with a focusing apron designed as a screen apron or a woven apron. Additionally, the suction airflow generated via the suction opening can be reduced, so that the focusing function of the focusing device is stopped without the risk of thread blockage or thread breakage.

Preferably, the cover opening is designed as a suction opening that cooperates with the focusing apron.

According to a first alternative, the cover opening is designed as a suction slit that cooperates with a focusing apron that is designed as a screen apron or a woven apron. The orientation of the suction slit can basically be carried out arbitrarily, for example parallel to the conveying direction. It is also possible to design the suction slit so that it tapers in the direction of conveyance of the sliver, in which case the focusing effect is strengthened.

However, according to a particularly preferred embodiment of the invention, the suction opening extends obliquely to the transport direction of the sliver. A corresponding configuration likewise increases the focusing effect, in contrast to the suction slits oriented parallel to the direction of conveyance of the sliver, with the additionally oblique direction of extension imparting a light false twist to the sliver. This, together with the frictional effect of the conveyor belt, allows the edge fibers to wrap around the sliver even better.

According to a second alternative, the cover opening is designed as a suction opening that cooperates with a focusing apron with perforation tracks extending in the direction of fiber transport.

It is also possible for the suction air supply itself to be designed, ie without a cover, as a suction opening cooperating with the focusing apron. A focusing device according to the invention may include only one cover. This single cover preferably has a cover opening designed as a suction slit, which cooperates with a focusing apron designed as a screen apron or a woven apron. In order to be able to exchange the focusing system, the suction air supply can be designed as a suction opening that cooperates with the focusing apron with perforation tracks. To replace the focusing system, it is only necessary to remove the cover and replace the focusing apron.

Alternatively, the focusing device can also include a second cover. In this configuration, the first cover has a cover opening formed as a suction slit, preferably cooperating with a focusing apron formed as a screen apron or a woven apron, and the second cover has , preferably has a cover opening designed as a suction opening cooperating with a focusing apron having a perforation track.

The positioning of the cover on the base body in a fixed and removable manner can basically be done as desired. However, according to a particularly preferred embodiment of the invention, it is proposed that the base body is designed in such a way that it accommodates the cover flush with the sliding surface in the suction air supply.

According to this embodiment of the invention, the suction air supply has a receiving area, in which the upper surface of the cover arranged on the suction air supply is located on the base body for accommodating the cover. , are formed flush with the area surrounding the cover. This configuration of the invention ensures a particularly trouble-free and reliable operation of the focusing device, in particular the friction-free circulation around the base body of the focusing apron, which is in contact with the top surface of the cover and the sliding surface of the base body. Guaranteed movement.

What is important for the functioning of the focusing device is that the cover is positioned securely on the base body when the cover is in use. Such an arrangement can basically be made arbitrarily, but according to a particularly preferred embodiment of the invention, it is proposed that the cover can be latched to the base body. The lockability ensures a reliable placement of the cover and thus trouble-free operation of the focusing device. The locking configuration can be obtained, for example, by spring-acting locking elements, clamping elements or magnetic elements, which ensure a secure but releasable positioning of the cover upon actuation. do.

The invention furthermore relates to a drafting device for a spinning machine, in particular a ring spinning machine. The draft device according to the invention is characterized in that it has a focusing device with one or more of the configurations described above. The focusing device is arranged in a manner known per se downstream of the exit roller pair of the drafting device.

The invention furthermore comprises a suction air supply arranged in the base body and a suction opening to which suction air is supplied from the suction air supply, that is to say suctioned by negative pressure, above the suction opening. One or more of the above-described configurations for a spinning machine, in particular a ring spinning machine, for bundling drafted sliver, with a focusing unit, in which a focusing apron is exchangeably arranged. The present invention relates to a method for operating a focusing device having the following configuration. According to the invention, the use of a cover with a cover opening for covering the suction air supply changes the suction opening for actuating the focusing unit. For this purpose, the base body is designed to releasably accommodate a cover covering the intake air supply.

A cover can be attached or removed to change the suction opening. The focusing device can thus be operated with or without a cover, depending on the required suction opening. In order to change the suction opening, the cover can also be replaced with a second cover with another cover opening.

By modifying the suction opening according to the invention in combination with the installation of a suitable focusing apron, the focusing system can be easily modified.

Next, one embodiment of the present invention will be described with reference to the drawings.

FIG. 3 is a perspective view of the base body of the focusing device with a cover separated from the base body; FIG. 2 is a perspective view of the base shown in FIG. 1 with a cover inserted; FIG. 2 is a perspective view showing the base body shown in FIG. 1; FIG. 2 is a plan view showing the base body of FIG. 1 without a cover. FIG. 2 is a plan view showing the base body of FIG. 1 together with a cover. 1 is a plan view of a focusing device with a perforated focusing apron; FIG. 1 is a plan view of a focusing device with a cover inserted into the base body and a focusing apron formed from a woven fabric; FIG. FIG. 3 is a plan view of the focusing device without a cover inserted into the base body and without a focusing apron made of a woven fabric;

5 to 7 show the focusing device 1 in different operating states and with different combinations of focusing aprons and suction openings. The central structural element of the focusing device 1 is the base body 2 shown in FIGS. 1 to 4b. This base body 2 is designed as an apron cage in the embodiment shown and has two suction shoes 4 arranged one after the other at a distance, each suction shoe 4 having a supply of suction air. It is equipped with part 5. In order to detachably arrange the cover 6 on the suction shoe 4, the suction air supply part 5 has a notch 13 that matches the shape of the cover 6, and this notch 13 connects the flange 15 with the flange 15. a surrounding edge 14; At this time, the notch 13 is formed so that, in the position shown in FIG. The dimensions are set to . The cover 6 arranged on the suction shoe 4 ensures that the suction air is guided only through the cover opening 7 of the cover 6 . The cover opening 7 is designed in this example as a suction slit, which extends obliquely to the running direction of the sliver 23 in the position where the cover 6 is attached to the suction shoe 4 .

In order to supply suction air to the suction air supply 5, the base body 2 has suction pipe connections 16 connected to the suction air supply 5, these suction pipe connections 16 being Used for connection to a suction air source (negative pressure source), not shown.

In order to place the base body 2 in a drafting device, not shown here, or to facilitate the transport of the focusing apron, the base body 2 has a semicircular receiving opening 19. This allows a coaxial arrangement of the base body 2 on the supply roller 12. The feed roller 12 can be driven by a bottom roller of the drafting device, which extends along the machine length (not shown). In the position shown in FIGS. 5 to 7, in which the base body 2 is thereby mounted on the drafting device, the feed roller 12, seen in the direction of travel of the sliver, is in each case one of the suction shoes 4 and one of the apron cages. It is located in the area between the deflecting rollers 17 that deflect the focusing aprons 8a, 8b, and these deflecting rollers 17 are also a component of the focusing unit 3, like the suction shoe 4 and the focusing aprons 8a, 8b. It is.

The focusing aprons 8a, 8b are guided by an apron cage. The focusing apron 8a, 8b is guided through between the web 18 and the deflection roller 17. The web 18 and the deflection roller 17 form a guide 11 . In order to prevent the focusing aprons 8a, 8b from sliding out laterally from the deflection roller 17 of the focusing unit 3 and the suction shoe 4, the focusing aprons 8a, 8b are connected on one side to the side guide elements 22 in the base body 2. is in contact with. The other side of the focusing apron 8a, 8b is guided via a guide surface 25 of a side guide element 24, which extends transversely to the longitudinal axis of the deflection roller 17.

In a first variant of the focusing device 1, shown in FIG. is transmitted to the sliver 23 via the hole 10 forming the sliver 23. In the embodiment of the focusing device 1 shown in FIG. 5, no cover 6 is arranged on the suction shoe 4, so that the suction air is transmitted to the sliver 23 only via the perforation track 9.

The base body 2 allows a simple modification of the structure of the focusing device 1 if necessary. For this purpose, the focusing apron 8a can be removed from the base body 2. In a second variant of the focusing device 1, the focusing device 1 is formed from a breathable woven fabric after the insertion of the cover 6 into the cutout 13 in the suction shoe 4, as shown in FIG. It can be operated using a focusing apron 8b. In this case, the sliver 23 is brought together via the suction air guided through the cover opening 7, which is formed as a suction slit.

If focusing is not desired, the focusing device 1 can be operated in the third variant shown in FIG. The focusing apron 8b is made of breathable woven fabric. If at the same time the intake air is reduced to such an extent that guidance of the fibers of the sliver 23 is still guaranteed, the focusing device 1 can be operated without a focusing function.

In another variant, not shown in the drawings, a second cover with a relatively large cover opening can be provided, which allows focusing by means of a focusing apron 8a with perforation tracks 9. With this configuration, this second cover, in conjunction with the focusing apron 8b made of breathable woven fabric, can also enable operation without a focusing function.

1 Focusing device 2 Base body 3 Focusing unit 4 Suction shoe 5 Suction air supply section 6 Cover 7 Cover openings 8a, 8b Focusing apron 9 Perforation track 10 Hole 11 Guide 12 Supply roller 13 Notch 14 Inner edge 15 Flange 16 Suction pipe connection section 17 Direction changing roller 18 Web 19 Accommodating opening 20 Sliding surface 21 Upper surface 22 Side guide element 23 Sliver 24 Side guide element 25 Guide surface

Claims (12)

A focusing device (1) for a spinning machine, in particular a ring spinning machine, for bundling drafted slivers (23), comprising a focusing unit (3), the focusing unit (3) comprising a base body; (2), and a suction opening to which suction air is supplied from the suction air supply part (5), and a focusing apron (8a) is provided above the suction opening. , 8b) are exchangeably arranged,
The focusing unit (3) comprises a cover (6) with a cover opening (7) for covering the suction air supply (5);
The base body (2) is formed to releasably house the cover (6) that covers the intake air supply section (5),
By using the cover (6), the suction opening for actuating the focusing unit (3) is variable;
A focusing device (1) characterized by: the cover opening (7) is designed as a suction opening cooperating with the focusing apron (8a, 8b);
Focusing device (1) according to claim 1. the cover opening (7) is designed as a suction slit cooperating with the focusing apron (8b), which is designed as a screen apron or a woven apron;
Focusing device (1) according to claim 1 or 2. the cover opening (7) is designed as a suction opening cooperating with the focusing apron (8a) with a perforation track (9) extending in the fiber transport direction;
Focusing device (1) according to any one of claims 1 to 3. the suction air supply (5) is designed as a suction opening cooperating with the focusing apron (8a, 8b);
Focusing device (1) according to any one of claims 1 to 4. The focusing device (1) includes a second cover;
Focusing device (1) according to any one of claims 1 to 5. The base body (2) is formed to accommodate the cover (6) flush with a sliding surface in the intake air supply section (5).
Focusing device (1) according to any one of claims 1 to 6. The cover (6) is lockable to the base body (2).
Focusing device (1) according to any one of claims 1 to 7. Drafting device for a spinning machine, in particular a ring spinning machine, characterized in that it is provided with a focusing device (1) according to one of the claims 1 to 8. It has a suction air supply part (5) arranged on the base body (2) and a suction opening through which suction air is supplied from the suction air supply part (5), and a focusing apron is placed above the suction opening. Claims 1 to 8 for a spinning machine, in particular a ring spinning machine, for bundling drafted sliver (23), with a focusing unit (3), in which the (8a, 8b) are exchangeably arranged. A method for operating a focusing device (1) according to any one of the preceding claims, comprising:
The use of a cover (6) with a cover opening (7) for covering the suction air supply (5) changes the suction opening for actuating the focusing unit (3) and The base body (2) is formed to releasably house the cover (6) that covers the intake air supply section (5).
A method characterized by: installing or removing the cover (6) in order to change the suction opening;
The method according to claim 10. replacing the cover (6) with a second cover in order to change the suction opening;
The method according to claim 10.