US1355319A - Automatic apparatus for tensioning the warp in looms - Google Patents

Description

I. DUMAIL. AUTOMATIC APPARATUS FOR TEN-SIONING THE WARP IN LOOMS.

APPLICATION FILED MAY 22, i919.

1,355,319, Patented Oct. 12,1920.

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z v ibis/{10m i A 2 UNITED STATES PATENT OFFICE.

ISIDORE DUMAIL, OF ROUEN, FRANCE.

A IC AP A AT OR S QNING HE WAR? IN O M T 0 all whom it may concern:

Be it known that I, IsIDoRn DUMAIL, citizen of the French Republic, residing at Rouen, in the Department of Seine Infrieure, France, have invented an Improved Automatic Apparatus for Tensioning the arp in Looms, of which the following is a specification.

This invention has for its object to provide an improved a paratus for tensioning the warp in looms, the essentially characteristic feature of which consists in this, that the ordinary tension weights acting upon the warp-tensioning levers of the loom are replaced by springs whose strength is carefully adjusted and which exert upon the warp-tensioning levers an effort which is at its maximum when the warp beam is full, and which diminishes gradually as the warp nea-m is emptied, and produces a tension equal to m'Z when the warp is used up.

The diminution of the tension of the springs is controlled by a warp beam feeler, the end of which is always in contact with the warp threads wound on the beam.

The accompanying diagrammatic drawings illustrate by way of example a constructional form of this invention.

Figure 1 is a front elevation of the improved apparatus.

Fig. 2 is a side elevation of the improved apparatus in its two extreme positions.

a As in the known tensioning apparatus, the improved apparatus according to the present invention comprises a warp-tensioning lever 1 (Fig. 1) that exerts a tension upon a-chain 13 which is wound on the pulley 12 of the warp beam 11 and thereby produces a powerful braking action upon the said pulley, which is usually made of cast iron.

In order to exert this braking action in the place of the ordinary known weights, the warp-tensioning lever 1 is pulled down by the action of a spring 2 which is placed in tension when the warp beam is filled, by the downward rocking movement of the lever 8 (Fig. 2) one end of which is fixed to the spring 2. while its other end is attached to a shaft 15 fixed to the frame of the loom.

This lever 8 is held in its lower position by the action of the warp beam feeler which operates in the following manner:

Upon a shaft 5 fixed to the frame of the loom there are fixed two arms, one (4) of which ends in a roller 3 (Figs. 1 and 2) lying Specification of Letters Patent.

Patented Oct. 12, 1920.

Application filed May 22, 1919. Serial No. 298,994.

upon the warp threads from one end to the other of the warp beam. The other arm 6 exerts through its roller 7 a pressure upon the lever 8 which latter is caused by this pressure to rock on its axle 15, and thus by its end 10 to exert a pull upon the spring 2. The braking action is then applied to the down by the warp-tension lever 1.

As the warp beam empties, the roller (Figs. 1 and 2) comes nearer to the center of the warp beam, and as will be readily perceived on reference to the figure, the lever 8 will rise and thus diminish the force of the spring 2 which will then exert a less great effort upon the warp-tension lever 1.

his eifort will be m'l when, the whole of the warp having been unwound, the roller 3 has come in contact with the barrel of the warp beam.

It is to be understood that the more the warp is unwound from the warp beam, the greater will be the acceleration of the beam. As a matter of fact the perforated sheet metal roller in front of the loom, driven by the pawl of the regulator, will always draw in a unit of time the same length of thread. But as the turns situated near the center have a less circumferential length than the outer turns of the full warp beam, it will be necessary, in order that these inner turns shall deliver during the same period of time the same length of thread as the outer turns, that the warp beam shall rotate faster.

In order to enable the warp beam to rotate with a constantly increasing speed, it will be necessary that the braking action upon the pulley 12 which prevents its motion shall diminish exactly in the same proportion. This result is obtained by the arrangement of the warp beam feeler. Owing to the increased speed of the warp beam, the more warp it delivers and the quicker it delivers the warp, the faster the roller 3 of the arm 4, will come nearer to the center of the warp beam 11. Consequently the roller of the arm 6 will rise with an increase pulley 12 by the pull of the chain 13 drawn plified. For this reason it is less costly and can be mounted quickly upon any kind of loom.

The improved apparatus is suitable for all kinds of weaving, heavy or light cloths, provided the tension springs are calculated and correctly adjusted.

lVhen the over-seer places a warp upon the loom provided with the improved apparatus,'he takes care to assure that there is a correct pressure upon the threads. If this pressure is too great or too little, he can adjust this pressure by means of the screws 9 and 10 (Figs. 1 and 2).

He also adjusts the horizontal'position of the warp-tension lever 1 (Fig. 1) by means of the nut 14 which is provided on the end of the brake chain 13. The weaver then need not attend to the tension of the threads until the warp has been used up.

The improved automatic apparatus for tensioning the warp is very suitable for all looms because it assures a greater regularity of the weaving. It is, however, absolutely indispensable for automatic looms where the weaver who attends ten, fifteen or twenty looms has not sulficient time to shift the usual tension weights placed on the warptensioned levers.

Detailed devices (not hereinafter described) may be employed for preventing if necessary the roller 7 from coming into contact with the lever 8 for the purpose of removing temporarily the pressure in cases where the weaver should require to unwind the warp in order to repair some of its threads. V

It is to be understood that the improved apparatus as. hereinbefore described is given solely by way of example as a constructional form of this invention, the essentials of the invention consisting essentially in the replacing of the ordinary tension weights in apparatus for tensioning warp in looms, by any device comprising one or more springs of adjustable tension exerting upon the warp-tension levers of the warp beams, an elfort which isat its maximum when the warp beam is full and which diminishes according as the warp beam empties and produces a tension equal to m'l when the warp is used up the diminution of the tension .said brake pulley, a warp-tensioning lever acting upon said brake chain, an adjustable spring acting upon said warp-tensioning lever, a rocking lever connected to the spring, a rocking shaft, two arms fixed on said rocking shaft, a roller carried by one of said arms, bearing against the warp threads from one end to the other of the warp beam, anda roller carried by theother of said arms, exerting a pressure upon the rocking lever, so as to cause the latter to rock and thus produce a tension of said adjustable spring varying according to the filling of the warp beam, whereby the braking action of said brake pulley on the warp 'beam is modified through the medium of said warp-tensioning lever and said brake chain.

2. In a loom, a warp beam, means including a brake lever for retarding the movement of the heam, a rocking lever, a spring adjustably connected between said levers, a bell crank having arms of unequal length, a roller carried by the short arm and engaging the rocking lever at a less distance from its pivot than the point of attachment thereto of the spring, whereby as the filling of the warp beam becomes smaller, the tension of the spring will be lessened.

In testimony whereof I afiix my signature.

7 ISIDORE" DUMAIL.

Witnesses:

Genus DANZER,

, LUornN CnEsrrN.

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