US3643883A

US3643883A - Lap-detecting stop motion

Info

Publication number: US3643883A
Application number: US847335A
Authority: US
Inventors: Olivier Wuest
Original assignee: Maschinenfabrik Rieter AG
Current assignee: Maschinenfabrik Rieter AG
Priority date: 1968-08-08
Filing date: 1969-08-04
Publication date: 1972-02-22
Anticipated expiration: 1989-02-22
Also published as: FR2015258A1; GB1275974A; DE1940272A1; CH494832A; DE1940272B2

Abstract

There is disclosed a lap-detecting stop motion for thread transporting rolls of draw-winding, drawtwisting or takeup machines for processing endless filaments. Such stop motion comprises a feeler set closely to the roll surface, the feeler in its rest or idle position being arranged substantially in a plane containing the roll axis, wherein the feeler portion nearest to the roll can be deflected in the direction of the roll circumference.

Description

United States Patent Wuest Feb. 22, 1972 [54] LAP-DETECTING STOP MOTION [72] Inventor: Olivier Wuest, Winterthur, Switzerland [73] Assignee: Rieter Machine Works, Ltd., Winterthur,

Switzerland [22] Filed: Aug. 4, 1969 [21 Appl. No.: 847,335

[30] Foreign Application Priority Data Aug. 8, 1968 Switzerland ..12119/68 [52] US. Cl ..242/36, 19/.26, 28/7l.4, 57/80, 57/86, 226/10 [51] Int. Cl ..B65h 63/00 [58] field of Search ..242/36, 37, 39,18, 35, 5, 242/19, 57; 226/11, 10; l9/.26; 57/80-87; 28/71.4

[56] References Cited UNITED STATES PATENTS 7/ 1927 Scott ..19/ .26 6/1935 McKean ..242/19 2,084,810 6/1937 Jones ..226/11 3,081,046 3/1963 Barnes, Jr. et a1. ..242/36 3,169,716 2/1965 Furst ..242/36 3,512,690 5/1970 Fisher et a1. ..226/11 FOREIGN PATENTS OR APPLICATIONS 952,571 5/1949 France ..242/39 1,192,766 4/1959 France ..242/39 Primary ExaminerStanley N. Gilreath Attorney-Werner W. Klieman [5 7] ABSTRACT There is disclosed a lap-detecting stop motion for thread transporting rolls of draw-winding, drawtwisting or takeup machines'for processing endless filaments. Such stop motion comprises a feeler set closely to the roll surface, the feeler in its rest or idle position being arranged substantially in a plane containing the roll axis, wherein the feeler portion nearest to the roll can be' deflected in the direction of the roll circumference.

12 Claims, 4 Drawing Figures LAP-DETECTING STOP MOTION BACKGROUND OF THE INVENTION The present invention relates to a new and improved lap-detecting stop motion for the thread transporting rolls of drawwinding, drawtwisting or takeup machines for processin endless filaments.

In transporting endless filaments, hereinafter conveniently referred to as threads, usually a considerable portion of the circumference of a draw roll or separator roll is covered by thread wraps, and, in case of an end breakage or low thread tension, undesirable lap formation occurs relatively frequently, that is to say, the thread sticks to the roll and is no longer removed therefrom. This unfavorably influences the processing operation. The same adverse effect can occur on the takeup friction drums on which the thread takeup package rests even if, at best, the thread contacts the friction drum only at the contact point.

SUMMARY OF THE INVENTION Thus, a primary objective of the present invention is the earliest possible detection of such lap formations in order to avoid more severe disturbances and, furthermore, stopping the thread feed as immediately as possible after detection of such lap formations.

Stop motions for this purpose are already known to the art, in which a pivotable tangential feeler is set close to the roll, so that this feeler, in case of lap formation, is pushed aside and activates a switch which stops the machine. This arrangement, however, possesses the great disadvantage of relatively low sensitivity, activating the switch only if the lap already has reached a certain thickness. The triggering distance of the switch depends on the very small pivoting angle of the feeler and directly on the thickness of the lap forming on the roll, such thickness is particularly very small if fine deniers are processed.

Accordingly, the present invention is primarily concerned with the achievement of the aforementioned objective and the elimination of the disadvantages mentioned above, by means of a lap-detecting stop motion for thread transporting rolls of draw-winding, drawtwisting or takeup machines for processing endless filaments which is of the type comprising a feeler positioned or set closely to the roll surface. According to an important aspect of the invention the feeler in its rest or idle position is arranged substantially in a plane containing the roll axis or shaft and the feeler portion nearest to the roll can be deflected in the direction of the roll circumference. The feeler can be constructed in the form of a lever, wherein the portion disposed closest to the roll can, for instance, extend completely or only partially over the width of such roll. The lever can consist of a deflectable thin, flat spring or it can be rigid.

BRIEF DESCRIPTION OF THE DRAWING The invention will be better understood, and objects other than those set forth above, will become apparent, when con sideration is given to the following detailed description thereof. Such description makes reference to the annexed drawing wherein:

FIG. 1 is a schematic view of a draw-winding machine equipped with the inventive lap detecting stop motion;

FIG. 2 shows details of the inventive lap detecting stop motion;

FIG. 3 is an alternative design of a draw'winding location or position; and

FIG. 4 is a schematic view of a drawtwisting machine equipped with the inventive lap-detecting stop motion.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Describing now the drawing, and, referring more particularly to FIG. I, a monoor multifilament thread I is transferred from a suitable feed point (not shown) to a roll 2 and a separator roll 3 and from there to a draw roll 4 and a separator roll 5 both rotating faster. Then, thread 1 passes through a thread traversing device 6 onto a bobbin 7 resting on, and driven by, a drive roll 8. Closely set to drive roll 8 is a spring or resilient plate 10 deflectable in the direction of the roll circumference and mounted on a housing 9. Spring plate 10 is connected to a switch 11 which, via circuit 12, activates a thread cutting device 13 arranged above rolls 2 and 3 if spring plate 10 is deflected upwardly into the position indicated by dashed lines. Clearance between the surface of roll 8 and spring plate 10 is regulated by adjusting the screw 14 penetrating through a nonillustrated slot of plate 10. Depending on the triggering sensitivity desired, plate 10 can be set for clearances ranging from a=0.05 to 0.1 mm. without rendering the triggering distance needed for activation of switch 11 too small. For obtaining optimum performance it is advantageous if plate 10 is arranged in, or as closely as possible to, a plane comprising the axis or shaft of the roll on which laps are to be detected.

As an example, it can be stated that for a triggering distance it (FIG. 2) of switch 11 of approximately I mm., total deflection h of the plate 10 on the drive roll must be about 2 mm. At a draw roll diameter of R=50 mm. and a plate length of r=40 mm. to the pivoting point D corresponding to the position of screw 14 a deflection h results if thread wraps are wound to a thickness of S=0.07 mm. It can be seen from this that a very small thread lap thickness of S=0.07 causes a deflection of the plate on the roll which corresponds to about 17 times the small lap thickness, plate clearance being a=0.05 mm. This plate deflection can be used to activate a switch, as explained above. The formation of an undesirable lap thus can be suppressed at its very beginning if the thread immediately is cut by means of cutting device 13, i.e., if thread feed is stopped. As best seen by referring to FIG. 2, a pivotal rigid lever 10' pivotably arranged about an axis or shaft D can be substituted for an elastic thin plate 10, this rigid lever 10 can be constructed to be completely flat or only at its end confronting the roll.

The arrangement according to FIG. 3 differs from the one shown in FIG. I only in that here the thread after passing through the traversing thread guide 15 encircles about half the circumference of drive roll 16 before being wound onto bobbin 17. If a lap-detecting stop motion device 18, reacting fast as described above, is provided at the region of the drive roll 16 covered by the thread, the traversing thread guide 15 can be arranged very closely to drive roll 16 without danger of damage in case of lap formation. The particular advantage, however, is the possibility of keeping to a minimum the distance F between the traversing thread guide 15 and the thread takeup point A, as the shape of the package improves the closer to the takeup point A thread traversing is effected. In a winding unit without a lap detecting stop motion, or one which reacts only after a considerable lap thickness is built up, the traversing thread guide would have to be located farther away and distance F necessarily would increase so much that package build would be impaired. Arrangement of a lap-detecting stop motion at drive rolls 8 or 16 is of particular advantage as these rolls are the last elements in the thread path on which lap formation possibly can occur.

In drawtwisting machines, such as exemplified in FIG. 4, the lap detection device 19 of course must be arranged at draw roll 20, as shown, as here no lapping occurs on spindle 21, and at which the arrangement of a detecting device would not make sense. 1

Also, on a draw-winding machine according to FIGS. 1 and 3, the arrangement of an additional detecting device 22 (indicated with phantom or dashed lines in FIG. 1) at draw roll 4 can be considered, in order to also immediately detect laps forming there. This device is wired parallel into circuit 12.

It should be apparent from the foregoing detailed description that the objects set forth at the outset to the specification have been successfully achieved.

What is claimed is:

l. A lap-detecting stop motion for thread transporting rolls of draw-winding, drawtwisting or takeup machines for processing endless filaments, comprising a thread transporting roll, a feeler set closely to the roll surface, said feeler in its rest position being arranged substantially in a plane containing the roll axis, means mounting said feeler such that the feeler portion nearest to the roll surface is capable of deflecting in a direction along at least part of the roll circumference, separate cutting means arranged in spaced relationship from said feeler for cutting the thread upon lap formation at the thread transporting roll, and means operatively connecting said cutting means with said feeler for actuating said cutting means in response to detection of lap formation at said roll by said feeler.

2. A lap-detecting stop motion according to claim 1, wherein said feeler is in the form ofa lever,

3. A lap-detecting stop motion according to claim wherein said feeler comprises a thin spring plate.

4. A lap-detecting stop motion according to claim 2, wherein said lever is pivotably arranged on a fixed axis.

5. A lap-detecting stop motion according to claim 1, wherein said operatively connecting means includes an electric circuit, an electric switch for influencing said electric circuit, said feeler being operatively connected to said electric switch so that when said feeler is deflected said electric switch influences said electric circuit.

6. A lap-detecting stop motion according to claim 1, wherein said feeler is arranged at a thread package drive roll ofa draw-winding machine.

7. A lap-detecting stop motion according to claim 6, wherein said feeler is arranged at a portion of said drive roll transferring the thread to the thread package in the region which is covered by the thread 8. A lap-detecting stop motion according to claim I, wherein said feeler is arranged at a draw roll.

9. A lap-detecting stop motion according to claim 1, wherein said feeler is in the form of a lever, said lever possessing a substantially flat construction at the region of said feeler portion nearest the roll.

10. A lap-detecting stop motion according to claim 1. wherein said feeler is in the form of a lever, means providing a pivot point for said lever which is located substantially in said plane containing the roll axis.

11. A lap-detecting stop motion for thread transporting rolls of draw-winding, drawtwisting or takeup machines for processing endless filaments, comprising a thread transporting roll, a substantially flat, lightweight, quickly responsive feeler arranged closely to the roll surface, said feeler in its rest position being located substantially in a plane containing the roll axis, means mounting said feeler such that the feeler portion nearest to the roll surface is capable of deflection along at least a portion of the circumference of the roll, cutting means arranged in spaced relationship from said feeler for cutting the thread upon the formation of laps at the thread transporting roll irrespective of the position of the thread at the surface of such roll, and means operatively connecting said cutting means with said feeler for actuating said cutting means in response to detection of lap formation at said roll surface by said feeler.

12. A lap-detecting stop motion according to claim 11, further including a traversing thread guide located in close proximity to said roll for delivering thread thereto.

Claims

1. A lap-detecting stop motion for thread transporting rolls of draw-winding, drawtwisting or takeup machines for processing endless filaments, comprising a thread transporting roll, a feeler set closely to the roll surface, said feeler in its rest position being arranged substantially in a plane containing the roll axis, means mounting said feeler such that the feeler portion nearest to the roll surface is capable of deflecting in a direction along at least part of the roll circumference, separate cutting means arranged in spaced relationship from said feeler for cutting the thread upon lap formation at the thread transporting roll, and means operatively connecting said cutting means with said feeler for actuating said cutting means in response to detection of lap formation at said roll by said feeler.

2. A lap-detecting stop motion according to claim 1, wherein said feeler is in the form of a lever.

3. A lap-detecting stop motion according to claim 1, wherein said feeler comprises a thin spring plate.

6. A lap-detecting stop motion according to claim 1, wherein said feeler is arranged at a thread package drive roll of a draw-winding machine.

7. A lap-detecting stop motion according to claim 6, wherein said feeler is arranged at a portion of said drive roll transferring the thread to the thread package in the region which is covered by the thread.

8. A lap-detecting stop motion according to claim 1, wherein said feeler is arranged at a draw roll.

10. A lap-detecting stop motion according to claim 1, wherein said feeler is in the form of a lever, means providing a pivot point for said lever which is located substantially in said plane containing the roll axis.