Claims
- 1. A winding machine for winding thread into a package comprising:
- at least one chuck for supporting a thread package;
- a motor connected to said chuck for driving the chuck into rotation about a longitudinal chuck axis;
- a friction roll for contacting the circumference of a thread package on said chuck;
- means for driving said roll into rotation about a longitudinal roll axis;
- means or causing relative movement of said chuck and said roll towards and away from each other along a path extending generally transversely of said axes; and
- means independent of said motor for limiting said relative movement of said chuck and said roll towards each other to leave a space between said chuck and said roll at completion of said relative movement of said chuck and said roll towards each other.
- 2. A winding machine as claimed in claim 1 wherein the means for limiting said relative movement is a stop.
- 3. A winding machine as claimed in claim 1 wherein said space is approximately 1 millimeter.
- 4. A winding machine for winding thread into a package comprising;
- at least one chuck for supporting a thread package;
- first means for driving the chuck into rotation about a longitudinal chuck axis;
- a friction roll for contacting the circumference of a thread package on said chuck;
- second means for driving said roll into rotation about a longitudinal roll axis;
- means for producing a feed back signal representative of the speed of said friction roll; and
- control means for controlling the speed of rotation of said chuck in response to said feed back signal and for selectively adjusting the rotational force applied between said friction roll and a package on said chuck, said control means including a first adjustable setting device connected to said first means and operable to set a predetermined circumferential speed for said package and said roll, and a second adjustable setting device connected to said second means and operable selectively to adjust said second means to correspondingly adjust the rotational force applied between said friction roll and a package on said chuck.
- 5. A winding machine as claimed in claim 4 wherein said means for driving said friction roll comprises an asynchronous motor, said second adjustable setting device selectively adjusting the speed of said synchronous motor to thereby adjust said rotational force.
- 6. A winding machine for winding thread into a package comprising:
- at least one chuck for supporting a thread package;
- means for driving the chuck into rotation about a longitudinal chuck axis;
- a friction roll spaced from said chuck for contacting the circumference of a thread package being wound on said chuck;
- means for driving said roll into rotation about a longitudinal roll axis;
- control means for controlling the speeds of rotation of each of said friction roll and said chuck, said control means being conditionable to have a normal winding condition in which a feedback signal is provided from said friction roll to control said means for driving said chuck and a starting condition in which no such signal is provided and said friction roll is spaced from a package being wound on said chuck; and
- conditioning means to change the condition of said control means from said starting condition to said normal winding condition in response to contact of said friction roll with a thread package being wound on said chuck.
- 7. A winding machine as claimed in claim 6 wherein said control means is operable in said starting condition to control said speeds of rotation of the friction roll and said chuck individually and to match said speeds at said time of contact of the friction roll with a thread package on said chuck.
- 8. A winding machine as claimed in claim 6 wherein said control means includes means for varying the speed of rotation of the chuck in a predetermined manner while said control means is in said starting condition.
- 9. A winding machine as claimed in claim 8 wherein said control means comprises means operable to match the rotational speed of the package to the speed of said friction roll at the time of contact therebetween.
- 10. A winding machine as claimed in claim 9 wherein said control means is operable in said starting condition to cause rotation of said friction roll at contant speed and to cause rotation of said chuck in such manner that the rotational speed of the package is reduced during winding of a package prior to contact with said friction roll.
- 11. A winding machine as set forth in claim 6 wherein said control means includes selectively adjustable means for adjusting the rotational force supplied between said friction roll and the package wound on said chuck.
- 12. A winding machine as claimed in claim 6 wherein said conditioning means is responsive to separation of said chuck and said friction roll due to build-up of a package following contact between said roll and the package.
- 13. A winding machine as claimed in claim 12 wherein said conditioning means is a position sensing member.
- 14. A winding machine as claimed in claim 13 wherein said position sensing member is adapted to sense the position of said chuck on a predetermined path of movement thereof.
- 15. A winding machine as claimed in claim 6 wherein said control means comprises means to produce an output signal dependent upon the speed of rotation of said friction roll, said output signal providing said feed back signal when said control means is in said normal winding condition and said output signal being used by said control means to control the speed of said friction roll when said control means is in said starting condition.
- 16. A winding machine as claimed in claim 6 wherein said control means comprises means to produce an output signal dependent upon the speed of rotation of said chuck, said control means bieng responsive in said starting condition to said output signal to control said means for driving said chuck.
- 17. A winding machine as claimed in claim 16 wherein said control means comprises a regulator for controlling said drive means for said chuck, said regulator being responsive to said output signal when said control means is in said starting condition and being responsive to said feedback signal when said control means is in normal winding condition.
- 18. A winding machine as claimed in claim 17 wherein said control means includes means for varying the speed of said chuck in a predetermined manner while said control means is in said starting condition, said latter means including means for feeding a variable input to said regulator while said control means is in said starting position.
- 19. A winding machine as claimed in claim 6 wherein said control means is selectively adjustable when in said normal winding condition to adjust the rotational force applied between said friction roll and a package on said chuck.
- 20. A method of winding thread comprising the steps of:
- laying a thread upon a driven rotating chuck to form a package thereon while controlling the speed at which the thread is drawn into the package by controlling the speed of rotation of the chuck;
- causing a partially-formed package on the chuck to contact an independently driven friction roll in such manner that the circumferential speed of the friction roll equals the circumferential speed of the package at the time of contact, and
- thereafter maintaining the speed of the friction roll at a set value to control the speed at which the thread is drawn into the package.
- 21. A method as claimed in claim 20 comprising the step of controlling the speed of the chuck in such manner that the circumferential speed of the package is made equal to the circumferential speed of the friction roll at the time of contact.
- 22. A method as claimed in claim 21 including the step of controlling the speed of the chuck in such manner that the circumferential speed of the package is reduced during winding of the package prior to contact with the friction roll.
- 23. A method as claimed in claim 22 including the step of controlling the speed of the package to hold the speed of the friction roll constant after contact with the package at a speed equal to the speed of the friction roll before contact with the package.
- 24. A method as claimed in claim 20 comprising the steps of
- controlling the speed of the chuck and the speed of the friction roll by conditionable control means which changes from a first condition driving the chuck and the friction roll independently of each other to a second condition driving the chuck and the friction roll in dependence on each other in response to contact of the package with the friction roll, and causing the circumferential force applied by the friction roll to the package after said change to said second condition to be equal to the circumferential force applied by the friction roll to the package before said change to said second condition.
PRIOR ART
This invention relates to a machine for winding filament material into packages. The filament material may be a synthetic plastics material, e.g. polyester, polyamide or polypropylene. The filament material may be in the form of a monofilament or a multifilament structure, both of which types will hereinafter be referred to as a "thread".
It is currently common practice to form thread packages on a rotatable bobbin chuck, the drive for the packages, and hence the chuck, being derived from a friction drive roll contacting the circumference of the package--see for example U.S. Pat. No. 3,907,217. The speed of rotation of the package is a determinant for the speed at which thread is drawn into the package, which is vitally important to the spinning operation as it determines spinning conditions e.g. in the region of a spinneret from which a synthetic plastics thread is drawn and these in turn determine the characteristics of the thread. However, at speeds significantly higher than 5000 meters per minute, the slippage which occurs at the region of contact between the friction drive roll and the package becomes unacceptably high. Many proposals have therefore been made to drive the chuck directly during the winding operation and some of these proposals also retain the friction drive on the package surface, see for example U.S. Pat. Nos. 4,146,376 and 4,069,985, GB Pat. Nos. 944552 and 995185 and Japanese Published Patent Application No. 51-49026.
In the prior art, inadequate attention has been paid to the initial phases of the winding operation in which contact is first made between the friction drive roll and the package, bearing in mind that the speed of rotation of these parts may be extremely high.
The present invention relates to a winding machine for winding thread into a package comprising a chuck upon which the package forms during a winding operation and means for driving the chuck into rotation about a chuck axis extending longitudinally thereof. Normally, the thread windings of the package are formed upon a bobbin tube which is removably mounted upon the chuck. In this specification, the term "package" includes the bobbin tube when the latter is used.
The winding machine further comprises a friction roll for contacting the circumference of the package during a winding operation, and a drive means for driving the roll into rotation about a roll axis extending longitudinally thereof. Means are provided for causing relative movement of the chuck and the roll towards and away from each other along a path extending generally transversely of both the chuck axis and the roll axis. The arrangement is, however, such that a space is left between the friction roll and the package at completion of the relative movement of the chuck and the friction with the friction roll is made by reason of build-up of the roll towards one another. Thus, initial contact of the package package and not by reason of the relative movement of the chuck and friction roll towards one another. Means, for example an abutment means, can be provided to limit relative movement of the chuck and friction roll towards one another so as to provide the spacing at the completion of such movement.
Control means may be provided for controlling the speed of rotation of each of the friction roll and the chuck. The control means may be conditionable, having a normal winding condition in which a feedback signal is provided from the friction roll for use in controlling the drive means for the chuck, and a starting condition in which no such signal is provided. The control system may be conditionable in response to sensing of initial contact of the package with the friction roll, e.g. switch means responsive to such contact may be provided to change the control system from the starting condition to normal winding condition.
The control means may be operable to control the circumferential force applied between the friction roll and a package engaged by the roll. Preferably the control means is adjustable so that such circumferential force can be selectively adjusted. For example, if the friction roll is driven by an asynchronous drive motor, that motor can be regulated to provide a controlled output drive moment (within certain limits dependent upon the motor design) independent of the speed of the friction roll, which will be seperately regulated, when the control means is in its normal winding condition, by a feedback loop containing the contact between friction roll and package.
The control means may control the drive means for the chuck in such manner that the speed of rotation of the package is matched to the speed of rotation of the friction roll when contact is first made between the package and the roll. The control means may also be arranged to vary the speed of rotation of the chuck in a predetermined manner during build-up of the package prior to contact thereof with the friction roll. Normally, the rotational speed of the chuck will be varied in such a manner as to maintain the tangential speed at the circumference of the package equal to or slightly higher than the thread-line speed.
The feedback signal provided from the friction roll to control the drive means for the chuck is preferably a signal representing the circumferential speed of the roll. Since the roll has a constant diameter throughout the winding process, the speed of rotation of the roll is related to its circumferential speed by a constant factor. The signal can be derived from a tachogenerator associated with the friction roll. Since the drive for the package is derived from both the drive means for the chuck and the drive means for the friction roll, slippage between the roll and package can be eliminated so that the feedback signal representing the circumferential speed of the friction roll simultaneously represents the circumferential speed of the package.
The winding machine may include a substantially conventional traverse mechanism for reciprocating the thread longitudinally of the chuck axis to enable build-up of the package. The machine may also include a conventional threading-up mechanism to enable initial laying of the thread onto a rotating chuck. The chuck may be of generally conventional construction, and can be provided with means for catching a thread laid thereon and severing the thread from the threading means.
US Referenced Citations (7)
Patent Grant
4548366
