DEVICE FOR LOCALIZING AN EXCESS IN LENGTH IN A THREAD
United States Patent 3580444
This device, which is adapted to be interposed between a device for continuously supplying a thread and a device for intermittently conveying the thread, comprises first and second thread-guiding elements, between which is a space in which an excess in length in the thread can hang down from such elements in the form of a loop. A downward-directed nozzle is arranged adjacent to the first thread-guiding element, through which thread enters the loop, for discharging fluid downward along the descending leg of the loop in order to place the descending leg under tension so as to prevent the loop from tangling. The ascending leg of the loop is relatively free of tension.
US Patent References:
Process and apparatus for treating artificial filaments
Mummery - July 1945 - 2379824
Apparatus for producing bonded staple lengths of grouped filaments
Palmer - September 1958 - 2854059
Tape slack device
Maxey - May 1965 - 3185400
/1287172.html
Andrews - December 1918 - 1287172
Air blower for linearly feeding a continuous strand
Kelley - May 1953 - 2639487
Process and apparatus for treating artificial filaments
Mummery - July 1945 - 2379824
Apparatus for producing bonded staple lengths of grouped filaments
Palmer - September 1958 - 2854059
Tape slack device
Maxey - May 1965 - 3185400
/1287172.html
Andrews - December 1918 - 1287172
Air blower for linearly feeding a continuous strand
Kelley - May 1953 - 2639487
Application Number:
04/755260
Publication Date:
05/25/1971
Filing Date:
08/26/1968
View Patent Images:
Export Citation:
Assignee:
Machinefabriek V, Te Strake N. L. (Deurne, NL)
Primary Class:
Other Classes:
226/117, 66/132R, 226/97.400, 226/113, 28/194, 139/435.100, 28/272, 226/118.100
International Classes:
D03D47/00; B65H17/32
Field of Search:
226/7,97,113,118,117 242/182--185 28/1.4
Primary Examiner:
Schacher, Richard A.
Claims:
I claim
1. A device for localizing an excess in length in a thread, adapted to be interposed between a device for continuously supplying a thread and a device for intermittently conveying the thread, wherein the improvement comprises first and second thread-guiding elements between which is a space in which an excess in length in the thread can hang down from the thread-guiding elements in the form of a loop, a baffle extending downward from the first and second thread-guiding elements, adjacent and parallel to the loop of thread which hangs down from such elements, to shield the loop against air currents, and a downward-directed nozzle, arranged adjacent to the first thread-guiding element, through which the thread enters the loop, for discharging fluid downward along the descending leg of the loop in order to place the descending leg under tension so as to prevent the loop from tangling, the ascending leg of the loop being relatively free of tension.
2. A device according to claim 1, wherein the baffle is provided, along its two vertical edges, with two sidewalls for confining and shielding the two legs of the loop.
3. A device for localizing an excess in length in a thread, adapted to be interposed between a device for continuously supplying a thread and a device for intermittently conveying the thread, wherein the improvement comprises first and second thread-guiding elements, between which is a space in which an excess in length in the thread can hang down from the thread-guiding elements in the form of a loop, and a downward-directed nozzle, arranged adjacent to the first thread-guiding element, through which the thread enters the loop, for discharging fluid downward along the descending leg of the loop in order to place the descending leg under tension so as to prevent the loop from tangling a second downward-directed nozzle, the fluid discharging capacity of which is substantially smaller than that of the first nozzle, arranged adjacent to the second thread-guiding element, for discharging fluid downward along the ascending leg of the loop, the ascending leg of the loop being relatively free of tension.
1. A device for localizing an excess in length in a thread, adapted to be interposed between a device for continuously supplying a thread and a device for intermittently conveying the thread, wherein the improvement comprises first and second thread-guiding elements between which is a space in which an excess in length in the thread can hang down from the thread-guiding elements in the form of a loop, a baffle extending downward from the first and second thread-guiding elements, adjacent and parallel to the loop of thread which hangs down from such elements, to shield the loop against air currents, and a downward-directed nozzle, arranged adjacent to the first thread-guiding element, through which the thread enters the loop, for discharging fluid downward along the descending leg of the loop in order to place the descending leg under tension so as to prevent the loop from tangling, the ascending leg of the loop being relatively free of tension.
2. A device according to claim 1, wherein the baffle is provided, along its two vertical edges, with two sidewalls for confining and shielding the two legs of the loop.
3. A device for localizing an excess in length in a thread, adapted to be interposed between a device for continuously supplying a thread and a device for intermittently conveying the thread, wherein the improvement comprises first and second thread-guiding elements, between which is a space in which an excess in length in the thread can hang down from the thread-guiding elements in the form of a loop, and a downward-directed nozzle, arranged adjacent to the first thread-guiding element, through which the thread enters the loop, for discharging fluid downward along the descending leg of the loop in order to place the descending leg under tension so as to prevent the loop from tangling a second downward-directed nozzle, the fluid discharging capacity of which is substantially smaller than that of the first nozzle, arranged adjacent to the second thread-guiding element, for discharging fluid downward along the ascending leg of the loop, the ascending leg of the loop being relatively free of tension.
Description:
BACKGROUND OF THE INVENTION
The invention relates to a device for localizing an excess in length in a thread.
In textile machinery, particularly in looms in which a thread has to be inserted into the shed by jet action the circumstances are such that a thread which preferably is to be supplied from a thread package with a constant velocity and further has to be conveyed with a variable speed becomes periodically slack. Slackening of a running thread in textile machinery can be very dangerous because the thread can become entangled, owing to which the thread cannot be handled anymore. It is already known to provide an arrangement in which a thread runs in front of the mouth of a flat shaft and the excess in length in the thread can be taken up in the shape of a loop in this shaft. In such cases use is made of an airstream which runs across the path of the thread, owing to which the thread is subjected to a strong flutter. To avoid fluttering of the thread the shaft is adapted as a guide having two opposite walls close together between which a loop in the thread can be guided. A further drawback of such a device is the need of a relative long narrow shaft to keep the thread tensioned in the stream of air. When a considerable excess in length in the thread is to be localized consequently the shaft is long and it takes a considerable amount of time to remove the thread therefrom.
SUMMARY OF THE INVENTION
The object of the invention is a simple device for localizing an excess in length in a thread which makes possible a high conveying speed of the thread and in which the excess of length in the thread can be removed at any time.
According to the invention this is attained with a device which is characterized by a thread supply and a thread-conveying device, between which a jet nozzle for a fluid with guiding elements for the thread has been positioned in such a manner that the thread running from the supply device enters the path of the jet leaving the jet nozzle which thread is to be laterally drawn from the jet by means of the conveying device.
When the thread-supplying device is formed by rotating rollers drawing the thread from a thread package only a small jet nozzle is to be placed in the path of the thread which path is located by the rollers which constitute a thread-guiding element, or by a thread guide proper. The thread can be drawn laterally out of the jet at any moment and the jet nozzle can be continuously operative when the thread-removing device, such as that provided in looms e.g. a device for weft inserting is only periodically operative. As the thread has already a running speed by the action of the thread-supplying device only a small jet action of the jet nozzle will be sufficient because the jet leaving the jet nozzle need not be used for conveying the thread.
A further advantage of the device according to the invention is the tension to which the thread between the jet nozzle and the thread-supplying device is subjected and the supplying device can be situated at a considerable distance from the device for localizing the excess in length in the thread.
A practical embodiment according to the invention is attained in that the jet nozzle has been positioned with respect to a guide for the thread in such a manner that the thread leaving this guide runs parallel to the jet leaving the jet nozzle. The provision of such a guide near a jet nozzle is advantageous because the thread comes immediately in contact with the jet leaving the jet nozzle. By means of another thread-guiding element spaced laterally from the jet nozzle the thread can be removed laterally from the jet.
In a device according to the invention it is advantageous that a baffle has been situated parallel to a plane running through the jet leaving the jet nozzle and the thread which is laterally drawn from the jet. By the provision of such a baffle the thread will run quietly even when a large loop in the thread has been formed and no other air current created by moving parts of the textile machinery will disturb the loop in the thread. Further it is advantageous that the baffle has been provided with lateral projecting sidewalls encompassing the plane running through the jet and the thread laterally drawn from the jet, resulting in a limiting of the area in which the loop in the thread can be formed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a diagrammatic perspective view of the device according to the invention in a first embodiment, and
FIG. 2 shown a front view, partly in section of a device according to FIG. 1 in a second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The device for localizing an excess in length in a thread can be used in textile machinery in which a thread periodically has an increased running speed, without subjecting the thread to a high tension. Such circumstances occur e.g. in looms in which a thread is drawn from a thread package, which thread has to be inserted as a weft into the shed by jet action. When the jet leaving a weft-inserting nozzle acts on the thread this thread must not have a high resistance and the thread is to be supplied by a separate supplying device.
When considering FIG. 1 a thread 1 is drawn from a stationary thread package 2. A thread eye 3 has been situated above the thread package 2, which thread eye can be fastened to a part of the textile machinery. The provision of a thread eye has the advantage that a thread balloon can be formed when the thread 1 is drawn from the thread package 2 at a high speed. The thread 1 runs from the thread eye 3 to a thread guide 4. This thread guide 4 is positioned in front of two conical rollers 5 and 6. The thread runs over a part of the conical circumferential surface of the roller 5 and is pressed against same by means of a roller 6. The rollers 5 and 6 are driven e.g. by means of a separate driving mechanism or by means of a rotating shaft of a textile machine upon which the device according to the invention has been mounted. The position of the thread guide 4 can be adjusted in a direction parallel to the axis of the roller 5, owing to which the drawing speed of the thread from the thread package and further the supplying speed of the thread to the remaining part of the machinery can be accurately adjusted with a given speed of rotation of the roller 5 because the circumferential speed of that part where the thread 1 makes contact with the circumferential surface of the roller 5 is a measure for the running speed of the thread. Consequently a thread-supplying device is formed by the rollers 5 and 6. Further the thread 1 runs to a thread-removing device which device has been generally indicated by the reference numeral 7 in FIG. 1.
In the embodiment shown in FIG. 1 the thread-removing device 7 is adapted as a jet nozzle for a fluid, e.g. air under pressure. The jet nozzle is connected to a source 10 of a pressure medium, preferably air by means of a line 8 and a control valve 9 (diagrammatically shown). When now the control valve is controlled e.g. by a part which rotates synchronously with the textile machine in such a manner that at a certain moment air from the source 10 is admitted to the jet nozzle 7, the thread will be ejected from the nozzle 7 e.g. as a weft into a shed. As soon as the control valve 9 is closed the removing device for the thread, thus the jet nozzle 7, becomes inoperative whereas the thread-supplying device formed by the rollers 5 and 6 is still operative. The result of this is an excess in length of the thread, which excess will be received by the device according to the invention comprising a jet nozzle 11 which is directed in such a manner that the jet leaving the nozzle 11 is directed parallel to the thread delivered by the rollers 5 and 6. Preferably the thread guide 12 has been arranged near the jet nozzle 11. The thread supplied by the rollers 5 and 6 runs through the thread guide 12, which thread is stretched by the jet action of the jet nozzle 11. When now the jet nozzle 7 becomes operative the thread running through the thread eye 13 will be laterally drawn out of the jet leaving the jet nozzle 11. The part of the thread between the thread guide 12 and the thread eye 13 is indicated in FIG. 1. The jet nozzle 11 is connected to the source 10 for the fluid under pressure. As soon as the jet nozzle 7 becomes operative the loop in the thread 1 which is held in a stretched position at one side by the action of the jet nozzle 11 will be reduced e.g. into that state which is indicated by the reference numeral 1a.
In order to prevent a fluttering of the thread e.g. caused by air currents created by some moving parts of the textile machinery the device according to the invention is provided with a baffle plate 16. Further the baffle plate possesses upright walls 17a and 17b encompassing the path of the thread between the thread eyes 12 and 13. As mentioned above the rollers 5 and 6 form the thread-supplying device and the jet nozzle 7 forms the thread-removing device. The design and construction of the thread-supplying device and the thread-removing device, however, are independent of the construction of the jet nozzle 11. Instead of removing the thread by the jet action of the jet nozzle 7 the thread can be removed in a mechanical manner. The main purpose of FIG. 1 is to show how the excess in length in the thread between the rollers 5 and 6 and the jet nozzle 7 can be localized by the action and the arrangement of the jet nozzle 11.
In the embodiment shown in FIG. 2 a stationary thread package 2 with its thread eye 3 has been indicated again. Further the rollers 5 and 6 for drawing the thread 1 from the thread package are diagrammatically indicated. However the thread runs from the rollers 5 and 6 through a passage 18 of a ring nozzle 19. The ring nozzle 19 has been formed by a chamber in a block 21. A channel 20 debouches in the chamber of the ring nozzle 19. A fluid such as air under pressure can flow through the channel 20 to the ring nozzle 19 and a jet will leave this ring nozzle which jet will be formed around the thread 1. As a result of the influence of the ring nozzle 19 secondary air stream can be created in the passage 18 which will tension the thread leaving the rollers 5 and 6. The thread 1 will be conveyed laterally of the baffle 16 to a thread eye 13a. When the rollers 5 and 6 are positioned at a considerable distance from the ring nozzle 19 the passage 18 can be adapted accordingly. A channel 22 has been situated within the block 21 above the baffle 16, and the channel 22 is connected to the ring nozzle 19 and debouches through a mouth 24 near the thread eye 13a at that side of the block where the loop in the thread is to be formed. The channel 22 has been provided with an adjusting bolt 23 for choking the passage in the channel 22. A jet can thus be created at the mouth 24 of the channel 22 which jet intersects the thread near the thread eye 13a. By this arrangement the loop in the thread can be somewhat widened, owing to which the loop in the thread can have a comparatively large length.
A good device for localizing an excess of length in a thread can be attained with very simple means as appears from the embodiments shown in the drawing, without the need of a complicated construction. As indicated by the shape of the loop in FIG. 2, the ascending leg of the loop, like the ascending leg of the loop in FIG. 1, is relatively free of tension. That is true because the fluid-discharging capacity of the mouth 24, because of its small size and because of the choking action of the adjusting bolt 23, is substantially smaller than the fluid-discharging capacity of the relatively large nozzle 19. The relatively small stream of fluid discharged from the mouth 24 assists in keeping the loop flat when a relatively large loop is employed.
The invention relates to a device for localizing an excess in length in a thread.
In textile machinery, particularly in looms in which a thread has to be inserted into the shed by jet action the circumstances are such that a thread which preferably is to be supplied from a thread package with a constant velocity and further has to be conveyed with a variable speed becomes periodically slack. Slackening of a running thread in textile machinery can be very dangerous because the thread can become entangled, owing to which the thread cannot be handled anymore. It is already known to provide an arrangement in which a thread runs in front of the mouth of a flat shaft and the excess in length in the thread can be taken up in the shape of a loop in this shaft. In such cases use is made of an airstream which runs across the path of the thread, owing to which the thread is subjected to a strong flutter. To avoid fluttering of the thread the shaft is adapted as a guide having two opposite walls close together between which a loop in the thread can be guided. A further drawback of such a device is the need of a relative long narrow shaft to keep the thread tensioned in the stream of air. When a considerable excess in length in the thread is to be localized consequently the shaft is long and it takes a considerable amount of time to remove the thread therefrom.
SUMMARY OF THE INVENTION
The object of the invention is a simple device for localizing an excess in length in a thread which makes possible a high conveying speed of the thread and in which the excess of length in the thread can be removed at any time.
According to the invention this is attained with a device which is characterized by a thread supply and a thread-conveying device, between which a jet nozzle for a fluid with guiding elements for the thread has been positioned in such a manner that the thread running from the supply device enters the path of the jet leaving the jet nozzle which thread is to be laterally drawn from the jet by means of the conveying device.
When the thread-supplying device is formed by rotating rollers drawing the thread from a thread package only a small jet nozzle is to be placed in the path of the thread which path is located by the rollers which constitute a thread-guiding element, or by a thread guide proper. The thread can be drawn laterally out of the jet at any moment and the jet nozzle can be continuously operative when the thread-removing device, such as that provided in looms e.g. a device for weft inserting is only periodically operative. As the thread has already a running speed by the action of the thread-supplying device only a small jet action of the jet nozzle will be sufficient because the jet leaving the jet nozzle need not be used for conveying the thread.
A further advantage of the device according to the invention is the tension to which the thread between the jet nozzle and the thread-supplying device is subjected and the supplying device can be situated at a considerable distance from the device for localizing the excess in length in the thread.
A practical embodiment according to the invention is attained in that the jet nozzle has been positioned with respect to a guide for the thread in such a manner that the thread leaving this guide runs parallel to the jet leaving the jet nozzle. The provision of such a guide near a jet nozzle is advantageous because the thread comes immediately in contact with the jet leaving the jet nozzle. By means of another thread-guiding element spaced laterally from the jet nozzle the thread can be removed laterally from the jet.
In a device according to the invention it is advantageous that a baffle has been situated parallel to a plane running through the jet leaving the jet nozzle and the thread which is laterally drawn from the jet. By the provision of such a baffle the thread will run quietly even when a large loop in the thread has been formed and no other air current created by moving parts of the textile machinery will disturb the loop in the thread. Further it is advantageous that the baffle has been provided with lateral projecting sidewalls encompassing the plane running through the jet and the thread laterally drawn from the jet, resulting in a limiting of the area in which the loop in the thread can be formed.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 shows a diagrammatic perspective view of the device according to the invention in a first embodiment, and
FIG. 2 shown a front view, partly in section of a device according to FIG. 1 in a second embodiment.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
The device for localizing an excess in length in a thread can be used in textile machinery in which a thread periodically has an increased running speed, without subjecting the thread to a high tension. Such circumstances occur e.g. in looms in which a thread is drawn from a thread package, which thread has to be inserted as a weft into the shed by jet action. When the jet leaving a weft-inserting nozzle acts on the thread this thread must not have a high resistance and the thread is to be supplied by a separate supplying device.
When considering FIG. 1 a thread 1 is drawn from a stationary thread package 2. A thread eye 3 has been situated above the thread package 2, which thread eye can be fastened to a part of the textile machinery. The provision of a thread eye has the advantage that a thread balloon can be formed when the thread 1 is drawn from the thread package 2 at a high speed. The thread 1 runs from the thread eye 3 to a thread guide 4. This thread guide 4 is positioned in front of two conical rollers 5 and 6. The thread runs over a part of the conical circumferential surface of the roller 5 and is pressed against same by means of a roller 6. The rollers 5 and 6 are driven e.g. by means of a separate driving mechanism or by means of a rotating shaft of a textile machine upon which the device according to the invention has been mounted. The position of the thread guide 4 can be adjusted in a direction parallel to the axis of the roller 5, owing to which the drawing speed of the thread from the thread package and further the supplying speed of the thread to the remaining part of the machinery can be accurately adjusted with a given speed of rotation of the roller 5 because the circumferential speed of that part where the thread 1 makes contact with the circumferential surface of the roller 5 is a measure for the running speed of the thread. Consequently a thread-supplying device is formed by the rollers 5 and 6. Further the thread 1 runs to a thread-removing device which device has been generally indicated by the reference numeral 7 in FIG. 1.
In the embodiment shown in FIG. 1 the thread-removing device 7 is adapted as a jet nozzle for a fluid, e.g. air under pressure. The jet nozzle is connected to a source 10 of a pressure medium, preferably air by means of a line 8 and a control valve 9 (diagrammatically shown). When now the control valve is controlled e.g. by a part which rotates synchronously with the textile machine in such a manner that at a certain moment air from the source 10 is admitted to the jet nozzle 7, the thread will be ejected from the nozzle 7 e.g. as a weft into a shed. As soon as the control valve 9 is closed the removing device for the thread, thus the jet nozzle 7, becomes inoperative whereas the thread-supplying device formed by the rollers 5 and 6 is still operative. The result of this is an excess in length of the thread, which excess will be received by the device according to the invention comprising a jet nozzle 11 which is directed in such a manner that the jet leaving the nozzle 11 is directed parallel to the thread delivered by the rollers 5 and 6. Preferably the thread guide 12 has been arranged near the jet nozzle 11. The thread supplied by the rollers 5 and 6 runs through the thread guide 12, which thread is stretched by the jet action of the jet nozzle 11. When now the jet nozzle 7 becomes operative the thread running through the thread eye 13 will be laterally drawn out of the jet leaving the jet nozzle 11. The part of the thread between the thread guide 12 and the thread eye 13 is indicated in FIG. 1. The jet nozzle 11 is connected to the source 10 for the fluid under pressure. As soon as the jet nozzle 7 becomes operative the loop in the thread 1 which is held in a stretched position at one side by the action of the jet nozzle 11 will be reduced e.g. into that state which is indicated by the reference numeral 1a.
In order to prevent a fluttering of the thread e.g. caused by air currents created by some moving parts of the textile machinery the device according to the invention is provided with a baffle plate 16. Further the baffle plate possesses upright walls 17a and 17b encompassing the path of the thread between the thread eyes 12 and 13. As mentioned above the rollers 5 and 6 form the thread-supplying device and the jet nozzle 7 forms the thread-removing device. The design and construction of the thread-supplying device and the thread-removing device, however, are independent of the construction of the jet nozzle 11. Instead of removing the thread by the jet action of the jet nozzle 7 the thread can be removed in a mechanical manner. The main purpose of FIG. 1 is to show how the excess in length in the thread between the rollers 5 and 6 and the jet nozzle 7 can be localized by the action and the arrangement of the jet nozzle 11.
In the embodiment shown in FIG. 2 a stationary thread package 2 with its thread eye 3 has been indicated again. Further the rollers 5 and 6 for drawing the thread 1 from the thread package are diagrammatically indicated. However the thread runs from the rollers 5 and 6 through a passage 18 of a ring nozzle 19. The ring nozzle 19 has been formed by a chamber in a block 21. A channel 20 debouches in the chamber of the ring nozzle 19. A fluid such as air under pressure can flow through the channel 20 to the ring nozzle 19 and a jet will leave this ring nozzle which jet will be formed around the thread 1. As a result of the influence of the ring nozzle 19 secondary air stream can be created in the passage 18 which will tension the thread leaving the rollers 5 and 6. The thread 1 will be conveyed laterally of the baffle 16 to a thread eye 13a. When the rollers 5 and 6 are positioned at a considerable distance from the ring nozzle 19 the passage 18 can be adapted accordingly. A channel 22 has been situated within the block 21 above the baffle 16, and the channel 22 is connected to the ring nozzle 19 and debouches through a mouth 24 near the thread eye 13a at that side of the block where the loop in the thread is to be formed. The channel 22 has been provided with an adjusting bolt 23 for choking the passage in the channel 22. A jet can thus be created at the mouth 24 of the channel 22 which jet intersects the thread near the thread eye 13a. By this arrangement the loop in the thread can be somewhat widened, owing to which the loop in the thread can have a comparatively large length.
A good device for localizing an excess of length in a thread can be attained with very simple means as appears from the embodiments shown in the drawing, without the need of a complicated construction. As indicated by the shape of the loop in FIG. 2, the ascending leg of the loop, like the ascending leg of the loop in FIG. 1, is relatively free of tension. That is true because the fluid-discharging capacity of the mouth 24, because of its small size and because of the choking action of the adjusting bolt 23, is substantially smaller than the fluid-discharging capacity of the relatively large nozzle 19. The relatively small stream of fluid discharged from the mouth 24 assists in keeping the loop flat when a relatively large loop is employed.