US2077525A - Pneumatic safety device for thread working machines - Google Patents

Description

April 20, 19370 M. L. MENNESEON PNEUMATIC SAFETY DEVICE FOR THREAD WORKING MACHINES Filed Dec. 9, 1935 2 Sheets-Sheet l I VEWZOP Nance) Louis Mennetssaw Giiiorne 8 April 20, 1937. M. L. MENNESSON 2,077,525

PNEUMATIC SAFETY DEVICE FOR THREAD WORKING MACHINES Filed Dec. 9, 1955 {91 2 Sheets-Sheet 2 I 2,077,525 PATENT OFFICE PNEUMATIC SAFETY DEVICE-FOR THREAD WORKING MACHINES Marcel Louis Mennesaon, Neuilly-sur-Seine, France, asalgnor to Socit Anonyme Solex, Neuilly-sur-Seine, France, a corporation of France Application December 9, 1935, Serial no. sacs: In Belgium December 12, 1934 11 Claims.

The present invention relates to pneumatic safety devices for machines for the treatment of threads, or the like, of the kind in which the absence of a thread produces, due to an escape of fluid, a variation in the pressure of said fluid in a chamber. The invention is more especially, although not exclusively, concerned with machines of this kind adapted to work on threads, yarns,

wicks, or the like, of textile materials.

The object of the present invention is to provide a device of the kind above referred to which, while occupying but little space, is capable of controlling, in a safe and efllcient manner, the work'- ing of the machine with which it is associated.

The essential feature of the present invention consists in providing the chamber containing the fluid under pressure as above stated with at least one outlet adapted to cooperate with a corresponding valve adapted to be controlled by at least 20 one thread, yarn, or the like, and in fitting said chamber with an element, either deformable or movable, which under the influence of a drop of the pressure in said chamber resulting from the opening of said valve, is capable either of stop- 25 ping the machine or of operating a signal through an electric or pneumatic relay.

v Other features of the present invention will result from the following detailed description of some specific embodiments thereof.

Preferred embodiments of the present invention will be hereinafter described, with reference to the accompanying drawings, given merely by way of example, and in which:

Fig. 1 is a diagrammatic sectional view of a 35 device made according to a first embodiment of the invention;

Fig. 2 is a sectional view of a modification of a part of this device;

' Figs. 3 and 4 are views similar to Fig. 2, relat 40 ing to two other modifications, respectively;

Figs. 4a and 4b diagrammatically show, in vertical section on the line X'X of Fig. 4b and in plan view, respectively, a modification of the arrangement of Fig. 4;

Fig. 5 is a diagrammatic sectional view of a device according to the present invention;

Fig. 6 is a similar view of a device made according to a third embodiment of the invention;

Fig. '7 is a diagrammatic sectional view of the eombination of several devices according to the invention so as to control a single electric relay; Fig. 8 is a diagrammatic sectional view of a similar arrangement; Fig. 9 is a view similar to Fig. 8, showing a M modification; V

Fig. 10 is a similar view showing a device according to the present invention, equipped with a pneumatic relay.

In the following description, the word thread will be employed to designate any elongated material, obtained by drawing, extrusion, or otherwise, such for instance as a thread, yarn, wick, portion of a wick, combination of wicks, made of a textile, metallic, or other material.

The device according to the present invention includes a chamber l communicating, through an orifice or passage of restricted section 2, with a conduit 3 connected with a reservoir containing a gaseous fluid under pressure, for instance compressed air, at uniform pressure, or at a pressure variable within certain limits.

This chamber is further provided with at least one outlet 4 through which it can communicate with the atmosphere.

Furthermore,chamber I communicates,through a conduit 5, with a casing 6, in which is fitted a membrane 1 (or a. piston) upon the internal face of which the pressure existing in chamber I can act, while the atmospheric pressure acts on the external face of said membrane.

This membrane 1 is caused to act; for instance through a. rigid push-piece 8, on a control organ 9, for instance an oscillating lever, which acts either directly or indirectly, for instance through an electric relay, not shown in Figs. 1 to 7, fed with current through a contact Hi. This control organ 9 is thus capable of producing a modification of the working of the machine, or even the stopping thereof or of a portion thereof. It may also, according to the invention, operate an optical, acoustic, or other signal which permits of finding immediately the part of the machine where a fault in the working has occurred.

The arrangement of this control organ 9 is such that it is in the inactive position when the pressure in chamber l is normal. On the contrary, when this pressure drops, membrane (or piston) l moves downwardly and brings the cooperating elements of contact Ill together.

This drop of the pressure in chamber l is obtained in the following manner: a

The outlet orifice 4 of chamber is closed, in the example of Fig. 1, by a stopping device ll, such as an oscillating valve provided with a counterweight l2, upon which passes generally a single thread l3, either before or after the passage of said thread through the machine in which said thread is utilized. As shown by Fig. 5, I may, in some cases, cause several threads, for instance two, or on the contrary only a portion of a thread, for instance one half of a wick,

to pass upon element l Id.

Due to the tension, weight and friction oi. the thread, valve element H is held upon its seat with a strength suflicient for overcoming the pressure existing inside chamber I. When the thread breaks, this action on the thread disappears. valve l l opens automatically, and the air present underplessure in chamber I- can escape freely through orifice 4. The compressed air that is fed through orifice 2 is not suflicient for restor- 6 ing the initial pressure existing in-said chamber prior to the opening of outlet 4. Consequently, hmembrane I, or the like, moves downwardly, for instance under the action oi! its own weight, or of the weight of push-piece 8, or of a return 10 spring or the like, which closes contact II. The respective positions occupied by the parts at this time are shown in dottcd'lines in Fig. 1.

Whenthethreadhssbeenrepairedandvalve element again applied against its'seat, the initial ltpressureisrestm'edinchamber l,whichmoves membrane I or the like upwardly and brings back .control organ l 0-! into inactive position. 7 Instead of a membrane or piston, such as I, I might make use of any other manometric device capable of controlling an electric relay or-a pneumatic relay, or a signalling device. For instance I might make use of a mere U-shaped .tube containing an electricity conducting liquid adapted to cooperate with one or several elec- 2 'tric contacts connected tothe to be controlled from a distance.

Inthemodiiicationsshownbir s 2and3, the thread I! itself directly stops the outlet-of chamber I, beingengaged in a transverse pas- 'sage ll connected with said chamber (as' shown by l ig. 2), or being merely applied upon said outlet 4 (as shown by Fig. 3). Of course, in this case, the outlet is made of such a shape and size that the thread shall eflectively stop leakage between itself and conduit II, or, at least, shall permit only losses which can be compensated by the inflow of fluid through orifice I.

As a matter of fact, the arrangements according to Figs. 2 and 3 are capable of workingwhen 40 it is desired to stop the machine or operate a signal when, for some reason, the sectionof the thread undergoes a sudden reduction, suflicient for creating a leakage, past said thread, which the inflow through orifice 2 is not capable ofcompensating. I thus obtain a drop oi the fluid pressure inside chamber l which may be suflicient for bringing control organ 9 into operative position, 'for which position it indicates that something abnormal is taking place.

The modification of Fig. '4 follows directly from the embodiment ,ofl 'ig. 1; with the difference that valve element Ila and the counterweight are'combined into a single piece, capable of pivoting about an axis il andwhich serves to close outlet orifice 4, for instance through a ball valve 1!. -Piece lie, in which thread II is passing, forms a kind of U-shaped gutter It, the branches of which are'curved on the'inlet side so as to prevent the accumulation of matter. The center 3001 gravity of thewholeis located above carryapart ltionwhichthethreadtqbc controlled is normally applied, and at least one lateral extension is, arranged in line with the lateral extension llb of the main part Ila of the active portion of an adjacent detecting de- 6 vice. With this arrangement, the threads, which pass normally p n the main parts I6 and lie respectively, can, eventually, replace each other, for instance due to a crossing.v without ceasing. for this reason, to maintain the two-correspond- '10 ing detecting devices in the closing podtion.

Analogous detecting devices are shown in Figs. 5 and 6, and also, in a partial manner, in Figs. 7 .to 10. It should be well understood that Imaymakeuseofanyofthearrangements the other face of said membrane is subjected to theaction ofthepressureexistinginachamher 6% This last mentioned pressure is controlled by a device including a chamber II provided with two orifice of restricted section ll and II arranged in series, orifice ll opening into the atmosphere. Chamber i1 is fed with fluid through conduit 2, that is to say from the same source of fluid under pressure .as chamber 0. With this arrangement, the pressure existing in chamber II is always proportional to the feed pressure transmitted through condu'itl. whereby slight variations of this feed pressure are without consequence. As soon as the pressure drops inchamber l,dueto breakingof ithread II (opening ,of outlet 4) the pressure existing in chamber 0 which is not modified byifthis drop; causes membrane I to move downwardly. k

optical or acoustic signal, independent of the relay II, either electric or not, which is controlled y member I.

. chine, for instance by means of sleeves made ofaninsulatingmateriaLsuchasebonite.

circuit is then advantageously closed thmllh themassoftheapparatusasitisciearlyvisihle ontherilhthandsideofl'kflJnwhichitms beenmpmscdthat oneof thewires hadiust broken.

In'i'ig. 8 I haveshown in what manner an apshunt'with a conductor Il itsdf connectedin.

with current from a source 24 of alternating current. To the feed circuit of the primary 23, there is connected, in shunt, a second primary 25,

5 belongingto a second transformer, preferably identical-to the first mentioned one and advantageously including a test lamp or adjusting lamp 26. The respective secondaries 21, 28 of these transformers are connected in series and arrangedin' such manner that the inducted electromotive forces are in opposition. These secondaries feed current, preferably through a rectifier 29, to an electro-magnet 30- the armature 3| of which is connectedto the clutch lever 32 of the machine, which is provided with a counterweight 33.

Under normal conditions of working, the primary 23 is not fed with current and only primary 25 is connected to the source of alternating current 24'; Alternating current is fed to rectifier 29 and to electro-magnet 30, which keeps its armature 3| in the position for whichthe lever v 32 keeps the clutch inoperative engagement. If

one of the threads happen to break, for instance 25 a thread corresponding to the apparatus'shown on the right hand side of Fig. 8, the current also flows through primary 23 and as its secondary 21 is mounted in opposition with the secondary of the other transformer, which is constantly energized, the tension at the terminals of rectifier 28 and of electro-magnet 30 is reduced, eventually to 'zero, whereby counterweight 33 moves lever 32 into the position in which the clutch is disengaged, shown by Fig. 8.

When the thread has been repaired, a workman brings back lever 32 into the position that corresponds to the engagement of the parts of the clutch and the electro-mag'net maintains its armatur 3| in the corresponding position.

In the embodiment of Fig. 9, the contacting devices 3-"! are inserted in series in the feed circuit 2| of the primary 23 of a transformer the secondary 21 of which is connected, through rectifier 29, with electro-magnet 30, which works as 45 above described. When a thread breaks, contact I0 is cut off (contrary to what has been'supposed up to now) which causes the electro-magnet 30 to be de-energized. Furthermore, a test lamp I 8 may be connected in shunt to the terminals 50 of each relay 20, provided that its electrical resistance is sufiiciently high in order that, due to the cutting ofi of the circuit 2, the tension at the terminals of the electro-magnet is suiilciently reduced in order that its strength becomes lower 55 than the effect of the weight of 33.,

In the example shown by Fig. 10,'the clutch 32 is controlled by a pneumatic relay 35 including ,a piston 38 both of the faces of which are subjected-to the pressure of a gaseous fluid fed by 00 a reservoir 31 to which said fluid is supplied from any suitable source, for instance a pump 38, which may be actuated by a cam 40 driven by a moving organ of the machine.

5 The pressure that acts upon the upper face of 65 the piston always corresponds to that of reservoir 3'I owing to the communication aifordedby a passage of large section; ,On the contrary, the pressure that-acts on the lower face of the piston corresponds to that existing in a chamber 31 70 which can be placed in communication with chamber 3l'throu'gh'a calibrated orifice or small section 42 and a conduit 43. Under normal conditions of working, the pressures acting on the respective faces of piston 33 are equal and the 35 control lever not the machine occupies the position for which the clutch is let in. If, due to the I breaking of a thread, the pressure in the corresponding chamber 1 decreases, membrane 1 or the like is moved downwardly and it produces the displacement of a valve member 34, mounted either pivotally or otherwise, which cooperates with an orifice 4| provided in the wall of chamber 31 1. It follows that the. pressure in chamber 31 decreases and piston 38, urged by the higher pressure existing in chamber 31, moves downwardly. bringing lever 32 into the position corresponding to the disengagement of the clutch,

as shown by Fig. 10.

Once the thread has been repaired, the pressure increases inchamber I; the corresponding membrane I is moved upwardly and closes orifice 4|. The pressure in chamber 31 again-becomes equal to that existing in chamber 31 and the workman can bring lever 32 into its position corresponding to the clutch being let in.

It should be noted that chamber, or chambers, I, and also chamber 31 might be fed from the same source of fluid under pressure, forinstance pump 38.'

Of course, it is possible to. control, either through the same relay or through an auxiliary relay, any device for braking the machine, entering into action when the clutch is released, eitherin the manner above described, or in any other way.

In thepreceding description I have only considered the case in which, in chamber I, there exists an overpressure which drops when one or several of the outlet orifices 4 is opened. I might also, and with the same advantage, use any arrangement in which an outlet remains closed under normal conditions and automatically opens as soon as the thread breaks or its section suddenly decreases below a predetermined value. The device above described, which is both simple and eflicient, permits of automatically controlling the working of a machine by immediately bringing about an operation or operating a signal which permits of obviating the consequences of any defectuous operation.

In a general way,-while I have,-in the above description, disclosed what I deem to be practical and efllcient embodiments of the present invention, it should'be well understood that I do not wish to be limited thereto as there might be changes made in the arrangement, disposition and form of the parts without departing from the principle of. the present invention as comprehended within the scope of the accompanying claims.

What I claim is:

l. A device for use in a machine for working threads .and the like, which comprises, in combination, a casing including a chamber filled with a fluid at a pressure different from atmospheric pressure andhaving at least one outlet, valve means for controlling said outlet adapted to be operatlvely controlled by at least one thread element, so as to open when said thread is broken,

and a member movable in response to variations in the fluid pressure in said chamber produced by the opening of said valve means.

2; A device for use in a machine for working threads and the'like, which comprises, in combination, a casing. including a chamber filled with a fluid at a pressure different from atmospheric pressure and having at least one outlet, a valve cooperating with sald outlet arranged to be kept in closedposition by the presence of at least one thread element worked normally in said machine,

to operate when-saidthread element is missing, and a member movable in response to variations in the fluid pressure in said chamber produced 5. by the opening oi said valve.

3. A device for use in a machine ior working threads and the like, which comprises, in combination, a casing including a chamber having at least one outlet opening into the atmosphere and 10 an inlet oi restricted section, means for 'ieeding fluid under pressure to said chamber through said inlet, a valve for controlling said outlet arranged tobekeptinclosedpositionbythepresenceotat least one thread element normally worked upon 15 by said machine. yielding means for opening said valve adapted to operate when said thread element is missing and a member movable in re-' sponse to variations in the fluid pressure in said chamberproduced by the opening or said valve.

' 4.Adeviceaccordingtoclaim3inwhichsaid valveisarrangedtobedirectlyacteduponbysaid thread element, the yielding means for opening element.

acne yielding means for opening said valve adapted 8.Adeviceaccordingtoclaim3iurtherineludin: a second chamber havingtwo oriflces of restricted section connecting the inside of said second mentioned chamber respectively with the atmosphere and with said means for feeding fluid under pressure. and means for causing the fluid Pressure in said second mentioned chamber to act on said movable member in opposition to the action or the fluid in the flrst mentioned chamber.

7. A device according to claim 3 further including means operative by said movable member for stopping at least one part oi said machine.

8. A device according to claim 3 further including, signalling means, and means operative by said movable member -i'or actuating said signalling means.

9. 'In connection with a machine for working threadsandthelike,apluralityoi'devicesaccording to claim 3, and a common relay adapted tobe operated by any of these movable members.

10. Adevi'ce according to claim 3 further including an electric relay. a circuit for said relay, and a make'and break device in said circuit, said movable member of claim 8 constituting the active element of said make and break device.

'll. A device according to claim S'iurther in eluding a pneumatic relay, and means operative by said movable member tor operating said re- MARLEL N.

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