US3815349A

US3815349A - Clutch for a stretching mechanism is a spinning or twisting machine

Info

Publication number: US3815349A
Application number: US00262698A
Authority: US
Inventors: A Gardella
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-06-21
Filing date: 1972-06-14
Publication date: 1974-06-11
Anticipated expiration: 1991-06-11
Also published as: BE785163A; DE2226272A1; NL7208461A; GB1328769A

Abstract

A clutch for a stretching mechanism in a spinning or twisting machine in which a drivable stretching roller is connected to a co-axial drive shaft by a clutch which can be disengaged by a thread monitor with the aid of a stop motion in the event of the thread breaking, wherein the clutch comprises two halves one of which carries coupling elements, such as spring-loaded balls, which can engage corresponding catch bores in the other halfclutch, and a rotatable ratchet disc with tapered apertures through the larger ends of which the coupling elments can project is disposed between the two half-clutches, the ratchet disc being arranged to be braked by the stop motion on breakage of the thread so as to force the coupling elements out of engagement with the catch bores and thereby to disengage the clutch.

Description

United States Patent [191 Gardella 1 CLUTCH FOR A STRETCHING MECHANISM IS A SPKNNING OR TWISTING MACHINE [76] Inventor: Adriano Gardella, 248, via a1 Capo di Santu Chiara, Genoa, Italy 16146 [22] Filed: June 14, 1972 [21] Appl. No.: 262,698

[30] Foreign Application Priority Data June 21,1971 Italy 12763/71 [52] 11.5. C1 57/83, 192/24, 192/45 [51] Int. Cl. B0111 13/16, DOlh 13/18 [58] Field of Search 57/78, 83, 80, 79, 84-87;

[56] References Cited UNITED STATES PATENTS 2/1929 Schloz ..192/25 1/1943 Eason....

[ .lune 11, 1974 2,685,948 8/1954 Freeman et a1 192/25 2,807,131 9/1957 Bade 3,327,464 6/1967 HalleuX 3,385,044 5/1968 Anderson et a1. 57/83 X Primary Examiner-John Petrakes Attorney, Agent, or Firm-Larson, Taylor & Hinds 5 7] ABSTRACT A clutch for a stretching mechanism in a spinning or twisting machine in which a drivable stretching roller is connected to a co-axial drive shaft by a clutch which can be disengaged by a thread monitor with the aid of a stop motion in the event of the thread breaking, wherein the clutch comprises two halves one of which carries coupling elements, such as spring-loaded balls, which can engage corresponding catch bores in the other half-clutch, and a rotatable ratchet disc with tapered apertures through the larger ends of which the coupling elments can project is disposed between the two half-clutches, the ratchet disc being arranged to be braked by the stop motion on breakage of the thread so as to force the coupling elements out of engagement with the catch bores and thereby to disengage the clutch.

5 Claims, 5 Drawing Figures BACKGROUND OF THE INVENTION The invention relates to a clutch for stretching mech anisms in spinning or twisting machines, in which a drivable stretching roller mounted for free rotation is connected to a drive shaft disposed coaxially to it by a clutch adapted to be disconnected by a thread monitor with the aid of a stop motion in the event of a thread breaking.

In spinning or twisting machines having a plurality of juxtaposed spindles the stretching mechanisms associated with the individual spindles are driven by a common drive shaft which is connected to a roller in each stretching mechanism, for example a roller of the pair of feed rollers. This driven stretching roller in turn drives the other rollers or other parts, for example the belt or belts of the respective stretching mechanism. In the event of a thread breaking on one spindle, it is necessary to stop only the associated stretching mechanism, thereby interrupting the feeding of the sliver, while the spinning or twisting operation is continued with the other spindles. For this purpose the drivable roller of each stretching mechanism is connected to the drive shaft disposed coaxially to it by a clutch adapted to be disengaged by a thread monitor with the aid of a stop motion in the event of a thread breaking.

The problem underlying the invention consists in providing a clutch of this kind which has a particularly simple, space-saving, and economical construction and which in conjunction with ease of operation and great operational reliability is adapted to be automatically disengaged not only on the breaking of a thread but also in the event of disturbances, particularly the obstruction and braking of the running of the stretching mechanism.

SUMMARY In a clutch of the type described above this problem is solved according to the invention through the fact that a half-clutchsecured to rotate with the drive shaft and a half-clutch lying opposite thereto and secured to rotate with the drivable stretching roller are adapted to be connected together for simultaneous rotation by coupling elements which are movably mounted, axially parallel to the drive shaft or to the stretching roller, in one half-clutch and partly engage by their hemispherical ends, under the action of associated engaging springs, in corresponding catch bores in the other halfclutch, and that between the two half-clutches a ratchet disc, which is coaxial thereto and which is adapted to, be'braked or locked by the stop motion of the spinning or twisting machine in the event of a thread breaking, is mounted for free rotation and is provided with In this construction of a clutch for stretching mechanisms in spinning or twisting machines the hemispherical ends of the coupling elements of one half-clutch partly engage, in the operative position, through the wider end portion of each curved aperture in the ratchet disc, so as to penetrate into a corresponding catch bore in the other half-clutch. The clutch is consequentlyengaged and the drivable stretching roller is driven rotationally by the drive shaft, while the ratchet disc disposed between the two half-clutches also rotates at the same speed. In the event of a thread breaking, the ratchet disc is braked or locked by the thread monitor with the aid of the stop motion. Consequently, the coupling elements, which at first continue to rotate together with the stretching roller and the drive shaft, move towards the narrower end of the respective curved apertures of the ratchet disc and are thereby pressed out of the corresponding catch bores in the other half-clutch against the force .of their respective engaging springs. The clutch is consequently disengaged and the rotational connection between the stretching roller and the drive shaft interrupted. After the thread breakage has been mended, it is merely necessary to release the ratchet disc again. In consequence of a partial rotation in relation to the half-clutch provided with the coupling elements it then automatically resumes within a very short time its operating position in which the coupling elements come to lie in the region of the wider end portion of each aperture in the ratchet disc, so that their hemispherical ends can pass through these apertures in the ratchet disc and engage tion of the running of the stretching mechanism, that is in respective catch bores in the other half-clutch under the action of the associated engaging springs. The clutch is thereby rc-engaged.

In the event of disturbances, particularly the obstructo say if the half-clutch associated with the drivable stretching roller is heavily braked or stopped, the cou- BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings: FIG. 1 shows the pair of feed rollers of a stretching mechanism, equipped with the clutch according to the invention, for spinning or twisting machines, in side elecurved apertures which are angularly spaced around penetration of the hemispherical ends of the coupling elements and the engagement of each of them in a catch bore to a minimum width preventing the engagement of the hemispherical ends of the coupling elements in the catch bores.

vation,

FIG. 2 is a plan view of the pair of feed rollers shown in FIG. 1, on a smaller scale,

FIG. 3 is a longitudinal section through the drivable feed roller, connected by a clutch to the drive shaft, in the stretching mechanism shown in FIGS. 1 and 2,

FIG. 4 is a side elevation of the clutch viewed in the direction IV-IV in FIG. 3, and

FIG. 5 is a cross-section through the clutch on the line VV in FIG. 3.

DETAILED DESCRIPTION OF THEINVENTION FIGS. 1 and 2 of the drawings show the pair of feed rollers 1,2 of a stretching mechanism for spinning or twisting machines. The drivable feed roller 1 is freely rotatable on a drive shaft 3, which is common to all the stretching mechanisms of the spinning or twisting machine, but can be connected to said shaft by a clutch which will be described more fully below. The other feed roller may be in the form of a pressure roller. The drivable feed roller 1 is provided at one end with a coupling flange 4, which on its periphery is formed as a gear 5. This gear 5 meshes with a gear 6 which is rotationally fastened to the top guide roller 7 of a belt 8. Belt 8 is the belt of the tape stretching mechanism to which the sliver referred to hereinabove is fed. The drive for the belt 8 is therefore taken from the drive shaft 3 through the feed roller 1 and the pair of gears 5, 6. The belt 8 co-operates with pivotally mounted guide rollers 9.

In the embodiment illustrated the drivable feed roller 1 is mounted for free rotation on a bearing bush 10 which is mounted on the drive shaft 3, to which the bush is secured against relative rotation by a threaded pin 11, as can be seen particularly in FIG. 3. On the opposite side to that where the coupling flange 4 of the feed roller 1 is disposed the bearing bush 10 has a stop flange 12, which prevents axial displacement of the feed roller 1.

The clutch between the drivable feed roller and the drive shaft 3 consists of the aforesaid coupling flange 4 of the feed roller 1' and a coupling flange 14' mounted opposite the flange 4 on the bearing bush 10 and rotationally fastened to the bearing bush 10 or to the drive shaft 3 by threaded pins 13, as can be seen particularly in FIGS. 2 to 5. In the coupling flange 4 of the feed roller 1 there are provided blind bores 15 which are parallel to the axis and in each of which there is disposed a longitudinally slidable coupling ball 17 pressed by an engaging spring 16 outwards against the coupling flange 14 of the drive shaft 3. Part of the half of each coupling ball 17 which projects out of the respective receiving bore can engage in a corresponding catch bore 18 provided in the coupling flange 14 of the drive shaft 3.

Between the two coupling flanges 4, 14 a relatively thin ratchet disc 19 is mounted for free rotation on the bearing bush 10. This ratchet disc 19 has curved apertures 20 which are disposed on the pitch circle of the coupling balls 17 or of the catch bores 18 and are angularly offset in relation to one another with the same spacing as the coupling balls 17 or catch balls 18, as i]- lustrated particularly in FIG. 5. Each aperture 20 has a width which decreases progressively in the direction of rotation F of the drive shaft 3. The wide end of each aperture 20 is made so wide and is so shaped that a coupling ball 17 can project through the wider end portion of the aperture 20 and engage to the desired extent in a catch bore 18. The other, narrow end of each aperture 20 of the ratchet disc 19 has on the other hand so slight a width that a coupling ball 17 cannot pass through this narrower end portion of the aperture 20 to engage in a catch bore 18.

On its periphery the ratchet disc 19 is provided with projecting teeth 119, which cooperates with a pawl 21, as illustrated particularly'in FIG. 1. This pawl 21 is operated by a' rocking lever 22 in the stop motion (not shown) which is known per se and which responds to thread breakages in the spinning or twisting machine.

23 and 24 denote lubricant'passages for lubricating the sliding surfaces between the feed roller 1 and the bearing bush 10.

In the operative position of the clutch the pawl 21 assumes the released position shown in FIG. 1, in which the ratchet disc can turn unhindered. The coupling balls 17 of the coupling flange 4 connected to the feed roller 1 thus engage through the wider end portion of the apertures 20 in the ratchet disc 19 and in respective catch bores 18 in the coupling flange 4l'provided with the drive shaft 3, as illustrated particularly in FIGS. 3 and 5. The coupling flanges 4, 14 are consequently coupled together, that is to say the clutch is engaged and the drivable feed roller 1 of the stretching mechanism is rotationally driven by the drive shaft 3. The ratchet disc 19 disposed between the coupling flanges 41, 14 is likewise rotated.

When the thread monitor (not shown), which is known per se and is part of the stop motion, detects a thread break, for example between the stretching mechanism and the spinning or twisting spindle following it, the lever 22 of the stop motion is rocked to the left in FIG. 1 and brings the pawl 21 into engagement with the teeth 119 of the ratchet disc 19. The ratchet disc 19 is thereby held fast. The coupling balls 17, which at first continue to turn in the direction of rota tion F in FIG. 5 together with the feed roller 1 and the drive shaft 3, consequently move towards the narrower end of the respective curved apertures 20 in the stationary ratchet disc 19 and are consequently pressed out of the corresponding clutch bores 18 in the coupling flange 14 connected to the drive shaft 3, against the force of the appertaining engaging springs 16. The clutch is thereby disengaged, that is to say the rotational connection between the two coupling flanges 4, 14 and consequently between the feed-roller land the drive shaft 3 is interrupted. The feed roller 1 and the belt 8 of the stretching mechanism are stopped, while the drive shaft 3 together with the bearing bush 10 and resumes within a very short time the operating position shown in FIG. 5, in which the coupling balls 17 of the coupling flange 4 connected to the feed roller 1 come to lie in the wider end region of the apertures 20 of the ratchet disc 19 and engage through the apertures 20, under the action of the appertaining engaging springs 16, into the respective catch bores 18 in the coupling flange 14 connected to the drive shaft 3, as illustrated particularly in FIG. 1. The clutch is thereby re-engaged and the feed roller is again coupled to the drive shaft 3.'

In the event of obstruction to the running of the stretching mechanism, for example when the rotation of the feed roller 1 is obstructed or greatly braked by disturbances of any kind, the clutch described acts as an automatic overload or torque-limiting clutch. When a predetermined torque is exceeded, the coupling balls 17, which together with the coupling flange 4 of the feed roller 1 are braked in their rotational movement or held fast, are in fact pressed, against the force of the appertaining engaging springs 16 at the wider edge of the apertures 20, out of the corresponding catch bores 18 in the coupling flange provided on the drive shaft 3 and rotating in the direction of rotation F, whereby the clutch slips and the rotational connection between the 5 feed roller 1 and the drive shaft 3 is automatically disengaged.

The invention is naturally not restricted to the embodiment illustrated, but within the framework of the general principle of the invention a number of different solutions, which differ particularly in respect of construction, are possible. Thus, for example the coupling balls 17 may be mounted in the coupling flange 14 joined to the drive shaft 3, and the corresponding catch bores 18 provided in the coupling flange 4 connected to the feed roller 1. In addition, the clutch may be disposed between any other roller in the stretching mechanism and the respective drive shaft. Instead of the coupling balls '17 it is also possible to use cylindrical coupling elements which are axially slidable in the receiving bores and of which the outer end, directed towards the other half-clutch andpartly engaging in the catch bores 18, is made hemispherical. On the other hand, all the features which can be seen from the drawing and description, including constructional details, may also be integral parts of the invention in any desired combination.

I claim:

1. A clutch device for a stretching mechanism in a spinning or twisting machine including a stop motion mechanism actuated by a thread monitor in the event of a thread breaking, said clutch device comprising a stretching roller mounted for free rotation,

a drive shaft coaxial with said roller,

a clutch, which is disengaged responsive to actuation of the stop motion mechanism by the thread monitor, for coupling said drive shaft to said stretching roller, said clutch comprising a first clutch member mounted for rotation with said shaft, a second clutch member disposed opposite said first clutch member and rotatable with said stretching roller, a plurality of movable coupling elements, mounted in one of said clutch members for axial movement parallel to the longitudinal axis of said shaft, for coupling said first clutch member to said second clutch member, said elements including hemispherical ends and the other of said clutch member including a corresponding plurality of catch bores in which said hemispherical ends are received, a corresponding plurality of springs for urging the hemispherical ends of said coupling elements into engagementin said catch bores, and a ratchet disc, disposed between said clutch members coaxial therewith and mounted for free rotation, which is braked responsive to actuation of the stop motion mechanism by the thread monitor. said ratchet disc including a corresponding plurality of curved apertures therein angularly spaced about the circumference of a circle which is in registry with said coupling elements and said catch bores, said apertures having a width which progressively decreases in the direction of rotation of said drive shaft between a maximum width which permits the hemispherical ends of said coupling elements to at least partially penetrate said apertures so as to engage in said catch bores to a minimum width which prevents said coupling elements from engaging in said catch bores.

2. A clutch device as claimed in claim lwherein said stretching roller includes a flange which forms said first clutch member and wherein said drive shaft includes a coupling flange which forms said second clutch mem her.

3. A clutch device as claimed in claim 2 wherein said stretching roller is mounted for rotation on a bearing bush which is secured to said drive shaft to prevent rel ative movement therebetween, said coupling flange being affixed to said bush.

4. A clutch according to claim 1, wherein the coupling elements are in the form of balls.

5. A clutch according to claim 1, wherein the ratchet disc is provided on its periphery with teeth which cooperate with a pawl adapted to be operated by the stop

Claims

1. A clutch device for a stretching mechanism in a spinning or twisting machine including a stop motion mechanism actuated by a thread monitor in the event of a thread breaking, said clutch device comprising a stretching roller mounted for free rotation, a drive shaft coaxial with said roller, a clutch, which is disengaged responsive to actuation of the stop motion mechanism by the thread monitor, for coupling said drive shaft to said stretching roller, said clutch comprising a first clutch member mounted for rotation with said shaft, a second clutch member disposed opposite said first clutch member and rotatable with said stretching roller, a plurality of movable coupling elements, mounted in one of said clutch members for axial movement parallel to the longitudinal axis of said shaft, for coupling said first clutch member to said second clutch member, said elements including hemispherical ends and the other of said clutch member including a corresponding plurality of catch bores in which said hemispherical ends are received, a corresponding plurality of springs for urging the hemispherical ends of said coupling elements into engagement in said catch bores, and a ratchet disc, disposed between said clutch members coaxial therewith and mounted for free rotation, which is braked responsive to actuation of the stop motion mechanism by the thread monitor, said ratchet disc including a corresponding plurality of curved apertures therein angularly spaced about the circumference of a circle which is in registry with said coupling elements and said catch bores, said apertures having a width which progressively decreases in the direction of rotation of said drive shaft between a maximum width which permits the hemispherical ends of said coupling elements to at least partially penetrate said apertures so as to engage in said catch bores to a minimum width which prevents said coupling elements from engaging in said catch bores.

2. A clutch device as claimed in claim 1 wherein said stretching roller includes a flange which forms said first clutch member and wherein said drive shaft includes a coupling flange which forms said second clutch member.

3. A clutch device as claimed in claim 2 wherein said stretching roller is mounted for rotation on a bearing bush which is secured to said drive shaft to prevent relative movement therebetween, said coupling flange being affixed to said bush.

5. A clutch according to claim 1, wherein the ratchet disc is provided on its periphery with teeth which cooperate with a pawl adapted to be operated by the stop motion.