US2247307A

US2247307A - Weft fork for circular weaving looms

Info

Publication number: US2247307A
Application number: US341577A
Authority: US
Inventors: Pelce Henri
Original assignee: Saint Freres SA Soc
Current assignee: Dite Saint Freres SA Ste; Saint Freres SA Soc
Priority date: 1939-07-18
Filing date: 1940-06-20
Publication date: 1941-06-24
Anticipated expiration: 1958-06-24

Description

June 24, 1941. H. PELCE WEFT FORK FOR cmcumm wmvme LOOMS Filed June 20, 1940 Patented June 24, 1941 WEFT FORK FOR ClRgULAR WEAVING LOOM Hem-l Pelc, Flixecourt, France, assignor to Socit dlte: Saint Freres, Socit Anonyme, Paris,

France Application June 20, 1940, Serial No. 341,577

In France July 18, 1939 (Cl. 139-13) I 3 Claims.

The present invention has for object a weftfork adapted to be mounted on a circular weaving loom in order to stop the weaving when a weft thread is missed owing to its breaking or to the cop being spent.

This weft-fork essentially comprises a member pivoted on the shuttle in such a manner that, by rocking under the action of centrifugal force, it can close an electric circuit controlling one or more devices provided to stop the'loom and to operate when the weaving'is stopped, such as a device ensuring the uncovering of the shuttles, the disengagement of the drive for the fabric etc. Said pivoted member is normally held, by the tension of the weft which slides'against it, in

such a position that, notwithstanding the action of centrifugal force, the electric contact is opened; it results therefrom that said contact Said pivoted member is normally held, by the breakage or exhaustion of the weft.

An important consequence of this invention consists in the fact that the circuit controlling the stoppage of the loom is closed by the weftfork only when the loom is working and rotatively drives the shuttles, and when the weft is no longer under tension; consequently, when the loom is stopped and the weft has been tiedor the cop replaced, or when the loom is stopped for any reason independent of the weft threads,the circuit remains open even before the tension of the weft is re-established, so that no difficulty whatever is encountered in restarting the loom.

The utilisation of centrifugal force for causing the closing of the circuit thus offers an essential advantage over the use of a spring the action of which is independent of the rotation of the shuttles and hinders or prevents the loom being restarted as long as the weft threads are not stretched again.

Another feature of the invention consists in the fact that the pivoted member which is carried by the shuttle and on which acts the tension of said weft thread, is shaped-and arranged so that the thread passes in contact therewith by following a sinuous path and is thus subjected to the braking necessary for ensuring the required tension, without it being necessary to use the action of any other tensioning member between the cop and the point of insertion of the weft at the bottom of the shed.

An embodiment of the weft-fork according to the invention is illustrated in plan view in the accompanying drawing by way of example, in which the shuttle and its shoe are shown in partial section.

constantly electrically connected to the well ii through the medium of flexible points 9.

On the shoe i is pivoted at it. near the point where the weft it issues from the shuttle, a member or arm it of sinuous shape, provided with a contact finger it arranged opposite a contact-piece it which is mounted on the shoe and suitably insulated from the shuttle. This contact-piece is connected to a resilient wiper it which is secured on the outer side of the shoe and which slides against the conducting pins 5. The well 31s connected to one of the poles of a source of low voltage current, whereas the crown t, carrying the pins t is connected to the other pole.

The weft passes through the undulations of the arm It so that when it is stretched between the orifice oi the shuttle and its point of insertion in the fabric, it prevents said arm from pivoting in the direction of the arrow 1 under the action of centrifugal force and thereby holds the finger It spaced from the contact-piece it: no current can then pass from t to t. As soon as the ten: sion of the weft ceases during the operation of the shuttle, the it rocks about the pivot it in the direction of the arrow 1, the finger it presses on the contact-piece iii and the circuit of the source of electricity is closed through i, d, 1, it, it, it, it, t and i.

This circuit can comprise one or more relays serving to determine the stoppage of the loom,

the uncovering of the shuttle or any other useful efi'ects.

When the mishap causing the stoppage of the loom has been remedied by tying the broken weft or by replacing the spent cop, etc., and the loom is restarted, the re-stretching of the weft by its sliding through the undulations of the arm it will again hold said arm spaced away, in position for opening the circuit. v

It is to be understood that the loom can comprise any number of shuttles equipped in a similar manner; the stoppage oi the loom will be caused in the same way by the weft thread of any fork, constantly tending to space the finger l3' from the contact-piece ll; said spring acting, as the stretched weft thread, in antagonism to the action of centrifugal force, is sufiiciently weak so as not to annui the action of the latter during the operation of the loom, but suflicient to ensure the breaking of the electric circuit as long as the stopped loom is not restarted. In the case in which the speed of rotation of the loom is insuflicient for the rocking of the arm it or the like to be always ensured upon the breaking of the weft, a spring can also be added, acting on said arm in the same direction as centrifugal force in order to ensure the projection of the finger IS on the contact-piece II as soon as a breakage occurs, and furthermore, in order to cular row of members connected to the body ofthe frame of the loom.

2. In a circular weaving loom, the comblnation of a circular guiding track for the shuttles,

avoid the vibrations of the device during normal operation. These two springs having opposed actions can moreover be used concurrently provided that the relaxation of each of them is suitably limited.

A small weight'can eventually be mounted on the end of the rocking arm for increasing the effect of centrifugal force acting on said arm.

I claim:

1. In a circular weaving loom, the combination of a circular guiding track for the shuttles, said track being a conductor of electricity and electrically insulated from the body of the frame of the loom, a shuttle-carrier guided on said, track, a contact member of said shuttle-carrier, adapted to rub against said guiding track, a lever pivotally mounted on said shuttle-carrier and having an arm through which a weft thread issuing from the shuttle is adapted to pass, said arm being adapted to be held by the tension of said thread in a direction oblique relatively to said circular track, a contact finger rotatively connected to said lever and adapted to come in contact with said contact piece on the shuttle-carrier when centrifugal force causes said lever to pivot, the shuttle-carrier having a conducting horn electrically connected to said contact finger and adapted to constantly rub against a cirsaid track being a conductor of electricity an. electrically insulated from the body of the frame of the loom, a shuttle-carrier guided on said track, a contact member on said shuttle-carrier, adapted to rub against said guiding track, a lever pivotally mounted on said shuttle-carrier and having an arm of sinuous shape through which a weft thread issuing from the shuttle is adapted to pass with friction, said arm being adapted to be held by the tension of said thread in a direction oblique relatively to said circular track, a contact finger rotatively connected to said lever and adapted to come in contact with said contact piece on the shuttle-carrier when centrifugal force causes said lever to pivot, the shuttlecarrier having a conducting horn electrically connected to said contact finger and adapted to constantly rub against a circular row of mem- Pers connected to the body of the frame of the com.

3. In a circular weaving loom, the combination of a circular guiding track for the shuttles, said track being a conductor of electricity and electrically insulated'from the body of the frame of the loom, a shuttle-carrier guided on said track, a contact member on said shuttle-carrier, adapted torub against said guiding track, a lever pivotally mounted on said shuttle-carrier and having an arm through which a weft thread issuing from the shuttle is adapted to pass, said arm being adapted to be held by the tension of said thread in a direction oblique relatively to a said circular track, a contact finger rotatively connected to said lever and adapted to come in contact with said contact piece on the shuttlecarrier when centrifugal force causes said lever to pivot, the shuttle-carrier having a conducting horn electrically connected to said contact finger and adapted to constantly rub against a circular row of members connected to the body of the frame of the loom, said members being constituted by flexible points which are secured on a ring outside the shed andwhich pass between the warp threads so as to penetrate within the shed and to be rubbed by said horn.

HENRI PELCE.