US3379225A - Loom stopping apparatus - Google Patents

Description

April 23, 1968 TERUHIKO lCHlMl ETAL 3,

LOOM STOPPING APPARATUS Filed May 26, 1966 4 Sheets-Sheet 1 TIcHrMI,

I lnvenlorS M/ E A llorneyS April 23, 1 TERUHIKO ICHlMl ETAL LOOM STOPPING APPARATUS Filed May 26, 1966 4 Sheets-Sheet 2 Z. OZEKI y f V/MOY M lnvenlors Attorney:

April 23, 1 TERUHIKO ICHIMI ETAL LOOM STOPPING APPARATUS Filed May 26, 1966 4 Sheets-Sheet Q Y- SHI MOYAM A lnvenlor By id A llorneys April 23, 1958 TERUHIKO ICHIMI ETAL 3,379,225

LOOM STOPPING APPARATUS Filed May 26, 1966 4 Sheets-Sheet 4 Y SH/MOYAMA T? ICHLMI,

K. RKAHAsHI, AND 2. OZEKI Inventors zwdmk A tlorneys United States Patent 3,379,225 LOOM STOPPING APPARATUS Teruhlko Ichimi, Osaka, Keinosuke Takaliashi, Ako, Ziro Ozeki, Yokkaichi, and Yukishige Shimoyama, Kishiwada, Japan, assignors to Toyo Boseki Kabushiki Kaisha, Osaka, Japan Filed May 26, 1966, Ser. No. 553,173 Claims priority, application Japan, May 31, 1965,

40/32,358; Dec. 29, 1965, 40/81.,767

3 Claims. (Cl. 139-353) ABSTRACT OF THE DISCLOSURE A loom stopping apparatus for a loom having a sley and a warp shed forming means, said stopping apparatus comprising a light source and a photoelectronic element mounted on opposite ends of the sley and aligned so that the light source directs a beam of light against the photoelectronic element through the warp shed formed by the warp shed forming means, electromagnetic means coupled to said photoelectronic element and actuated thereby when the light intensity detected by said photoelectronic element changes due to a broken warp, loom stopping means coupled to said electromagnetic means and actuated thereby to stop the loom when the electromag netic element is actuated, and circuit breaking means coupled to said loom and to the circuit between said photoelectronic element and said electromagnetic means for breaking the circuit therebetween each time the Warp shed forming means changes the shed, whereby the loom stopping apparatus is not actuated to stop the loom except when the warp thread breaks.

The present invention relates to a loom stopping apparatus, and more particularly it relates to an apparatus adapted to electrically stop a loom when some defect occurs in warp threads on the loom.

In the conventional warp stopping apparatus, a thin flat plate (called a drop wire) is suspended for each warp thread and the falling of said drop wire at the time of the break of the corresponding warp thread is mechanically or electrically detected thereby to actuate a stop mechanism. In this case, however, the drop wires are positioned behind the heald frames, so that if a thread break occurs forwardly of the heald there will be a lag in detection and hence in the stopping of the loom, and during the lag the breaking end of the thread tends to entangle around the adjacent threads which, in turn, While the drop wire has not yet been down, are tightened in a position to divide the warp shed defined by the warp thread sheet divided into upper and lower parts, thereby forming an improper warp shed which causes weaving defects to the fabric. Such improper warp shed as mentioned above is caused not only at the time of yarn break but also by the nap, and particularly when filament yarns of silk, artificial silk or synthetic fiber are used as warp threads in weaving operation, such defects as mentioned above are caused in a stage of filament break before growing into yarn break.

An object of the invention is to provide an apparatus so arranged that when an improper warp shed occurs due to thread nap; filament break or yarn break, it detects the warp thread causing said improper warp shed and immediately stops the loom. Another object is to effect the detection in such a manner as not to touch the Warp thread thereby not to aggravate nap formation.

Briefly, a loop stop ing apparatus of this invention is characterized in that a light source and a photoelectronic element are provided in the rear of the sley of the loom so as to be opposed to each other, it being so arranged that a light beam issuing from said light source may pass through the warp shed formed during the driving of the loom and enter the photoelectronic element whereby when the amount of light incident to the photoelectronic element is varied the loom is stopped.

According to a preferred embodiment, said photo electronic element is a phototransistor, and the photoelectronic element and the light source are secured to the opposed ends of a beam long enough to substantially cover the reed space, said beam being secured to the rear surface of the sley through a packing having compressive resiliency interposed therebetween.

The invention will now be described in more detail with reference to the accompanying drawings wherein,

FIG. 1 is a plan view of the front half of a loom,

FIGS. 2, 3, 4 and 5 are sectional views taken along lines IIII, III-1II, IV-1V and V--V in FIG. 1 respectively.

The loom has right and left upstanding side frames 1, 1 which are interconnected at their front side upper surfaces by a breast beam 2. As is apparent from FIG. 1, there is provided a handle bracket 3 positioned on the right hand side of the breast beam 2 and extending therefrom. The handle bracket 3 has a substantially rectangular opening 4, the rear right hand edge thereof forming a notch 5 recessed toward the rear side of the loom. During the driving of the loom, a handle lever 6 is positioned in said notch 5. A crank shaft 7 is provided in the central portion of the loom so that it extends through the side frames 1, 1. Secured to said crank shaft are a brake wheel 8 and a spur gear 9 positioned outside the side frame 1 on the right hand side. A pulley 11 driven by V-belts 10, 1G, 10 is adapted to impart rotation to the crank shaft 7 through a conical friction clutch. A shifting lever indicated at 12 for effecting the engagement and disengagement of the clutch is adapted to transmit the rightward or leftward movement of the aforesaid handle lever 6 to the pulley 11 through a rod 13, lever 14 and shaft 15 (FIG. 4). These mechanisms are conventional, and although a detailed explanation thereof will be omitted it is to be noted that the handle lever 6 is adapted to be turned back and forth and also right and left, and is pulled backwardly and rearwardly by means of springs. If pushed to the right, the handle lever 6 will fit in said notch 5, and if it is forwardly pushed from this position it will be disengaged from the notch 5 to be returned to the position shown at 6, whereupon the clutch is disengaged and simultaneously the brake is actuated, so that the loom is stopped.

A sley 16 is composed by integrally coupling a wooden plate 18 on a channel beam 17. A square member 19 is secured to the rear surface of the sley. The lower edge of a reed 21 is fitted in a groove 20 provided on the upper surface of the joint portion between the wooden plate 18 and square member 19. The upper edge of the reed 21 is fitted in a groove 23 provided on the lower surface of a reed cap 22 so that the reed is fixed in position. The sley 16 executes back and forth movements in the course of the rotation of the crank shaft 7. In FIG. 2, when in the foremost position, the sley 16 and other parts are shown in solid lines, and when in the rearmost position they are shown in broken lines, the prime mark being applied to the reference numerals denoting the same parts. In the rear of the sley 16 there are a pair of heald frames 24 and 25 executing up and down movements, said heald frames 24 and 25 being provided with a number of wire healds indicated schematically at 26 and 27, respectively. Similarly indicated warp threads 30 and 31 passed through heald eyes 28 and 29, respectively, are caused alternately to assume upper or lower position so that they are divided into two groups,

upper and lower, to form sheds. The warp threads are woven together with weft threads to form a fabric 32 which, in turn, is forwardly moved for being wound.

The foregoing is an outline of the structure of the usual loom which is known per se. According to the present invention, as shown in FIGS. 1-3, there is provided a channel beam 34 secured to the rear surface of the square member 19 abutting against the rear surface of the sley 16 by means of bolts 35 and nuts 36, with a packing plate 33 having compressive resiliency such as sponge being interposed therebetween. The channel beam 34 is long enough to cover the reed space and may take any desired shape in cross-section so far as it is rendered hard to fiex. It is essential that in case that the sley 16 is distorted during the driving of the machine, the distortion be absorbed by the packing plate 33 and the beam 34 itself maintain its straight form. The upper surface of the beam 34 is made fiat and has at its opposed right and left ends plates 38 and 37 secured thereto and extending therefrom toward the right and left, respectively. Secured to the upper surface of the plate 38 positioned on the right as viewed toward the front of the loom is a box 39 having a lamp 40 mounted therein, as best seen in FIG. 3. Projecting from the right side of the box 39, as viewed toward the back of the loom, is a hood having at its end a window 41 with a diameter of 1-2 cm. so that a light beam will pass through the shed. On the other hand, the opposite plate 37 has a box 42 secured thereto and containing a phototransistor 43 which is one of the photoelectronic elements in such a manner as to be capable of receiving said light beam. Further, the box 42 has a hood projecting therefrom and having at its end a hole 44 with a diameter of 3-5 mm. positioned on the axis of light extending between said phototransistor 43 and said lamp 40. Further, in order to prevent excessive light beams from entering the phototransistor, the box 42 is sealed by a cover 45. The lamp 40 is connected to the terminal 49 of an amplifier 48 (FIG. 1) by lead wires 46 and 47. The phototransistor 43 is connected to the terminal 52 of the amplifier 48 by lead wires 50 and 51. The amplifier 48 has terminals 53, 54 and 55 besides said terminals 49 and 52, the terminal 53 being connected to a suitable electric source, the terminal 54 being connected to a solenoid 58 by lead wires 56 and 57, the terminal 55 being connected to a timing switch 62 by lead wires 60 and 61 (FIG. 1). The amplifier may be of the usual type, provided that it has little noise and high sensitivity and that there is no variation in voltage supplied to the lamp and phototransistor. Thus, when the amount of light incident to the phototransistor is varied, such variation is amplified enough to actuate the solenoid 58. As shown in FIG. 4, the solenoid 58 has a frame 63 and an iron piece 64, it being so arranged that when the solenoid 58 is actuated, the iron piece 64 is pulled toward the front of the machine (i.e. to the left, as viewed in FIG. 4). The frame 63 of the solenoid 58 is secured to the upper surface of a bracket 65 secured to the upper part of the front side of the right side frame 1 of the loom. The iron piece 64 is connected to the front end of a spindle 66 capable of moving back and forth by a pin 67. The spindle 66 has weft sensible forks 68 on its rear end and is supported by a bracket 69 as usual. Further, the spindle has a lever 70 by means of which it is possible to disengage the handle lever 6 from the notch when the spindle is moved forward (i.e. to the left, as viewed in FIG. 4). Thus, when the solenoid 58 is energized during the driving of the machine, the spindle is forwardly moved to release the handle lever 6 thereby to stop the loom. The timing switch 62 is adapted to render the phototransistor operative for a predetermined period of time when the crank shaft 7 executes one complete revolution. The opening and closing of the timing switch is controlled by a cam 71. The circuit including the timing switch is so arranged that if the amount of light received 4. by the phototransistor is varied during the closing of the timing switch, the aforesaid solenoid is actuated.

The cam 71 consists of two cam plates 72 and 73 of the same size and shape, each having a large diameter portion extending around an arc of degrees, the remaining portion being smaller diameter portion. These cam plates 72 and 73 are each capable of being independently fixed to the crank shaft 7. Thus, the cam 71 is so constructed that the larger diameter portion thereof can be varied within a range of 120 to 240 degrees by interlocking and circumferentially displacing the cam plates relative to each other.

The timing switch 62 is supported by an L-shaped bracket 74 secured to the side frame 1 on the left and has a spindle 75 movable toward and away from the cam 71 and is provided at its foremost end with a bowl 76 in rolling contact with the cam .71. The cam bowl 76 is contacted just with the joint portion between the cam plates 72 and 73 and is adapted to close the circuit when it is brought into contact with the larger diameter portion of the cam. With the cam 71 suitably set and when the loom is driven, the light beam scans through the shed along a broken line a shown in FIG. 2 during the back and forth movements of the sley. Thus, if there are, in the shed, improper warp threads 30 and 31 which would form an improper shed due to nap or yarn break, the light beam will be instantaneously interrupted so that the amount of light incident to the phototransistor is varied and hence the electric current flowing therethrough is varied. With the usual loom, a rate of change enough to amplify the aforesaid variation of electric current can be obtained because the sley is moving at a considerable speed. Generally, in order to increase the chance of finding the improper shed-forming warp threads 30' and 31', it is preferable that the time during which the timing switch 62 is closed be prolonged. However, this prolongation of the closing period of the timing switch is limited because of the fact that when the upper and lower warp threads are to be upwardly or downwardly separated after they have arranged on the same level, the movement of the Warp threads lags behind the movement of the healds so that it becomes necessary not to mistake the lagging warp threads for the improper shed-forming warp threads. In case of tappet shedding, the closing period of the timing switch preferably corresponds to an angular region of about 225 degrees defined extending about 90 degrees forwardly and about degrees rearwardly of the center of the dwell during one revolution of the crank shaft. In case of a loom using a shedding tappet and adapted to have its warp threads brought to the same level at the front dead center, a region extending from the bottom center to a 210 degree line may be used as the timing switch-closing region, though it would be necessary to change the design of the cam 71 since the dwell and also the time at which all the warp threads are brought to the same level vary according to the type of the loom. It :is, of course, supposed in that case that the crank shaft rotates in a counterclockwise direction (in the direction of arrow b in FIG. 5).

As is evident from the foregoing description, the present invention makes it possible to prevent the occurrence of weaving defects due to improper shedding occurrable in the course of Weaving operation.

Although the invention has been described with ref-- erence to a loom using a flying shuttle, it can be applied to other looms using no flying shuttle, for example, water jet looms and air jet looms, and it is also understood that modifications thereof may be made within the scope of the present invention.

What we claim is:

1. A loom stopping apparatus for a loom havinga sley and a warp shed forming means, said stopping apparatus comprising a light source and a photoelectronic element stationarily mounted on opposite ends of the sley and aligned so that the light source directs a beam of light against the photoelectronic element through each warp shed formed by the warp shed forming means, electromagnetic means coupled to said photoelectronic element and actuated thereby when the light intensity detected by said photoelectronic element changes due to a warp thread extending in said shed, loom stopping means coupled to said electromagnetic means and actuated thereby to stop the loom when the electromagnetic element is actuated, and circuit breaking means coupled to said loom and to the circuit between said photoelectronic element and said electromagnetic means for deactivating the circuit therebetween during each warp shed change by the warp shed forming means, whereby the loom stopping appartus is operable to stop the loom only when a warp shed is formed.

2. A loom stopping apparatus as claimed in claim 1 in which said photoelectronic element is a phototransistor.

References Cited UNITED STATES PATENTS 963,100 7/1910 Williams et a1. 139-352 2,711,093 6/1955 Edelman et a1. 139-353 3,139,911 7/1964 Breitmeier 139-370 FOREIGN PATENTS 330,444 7/ 1958 Switzerland.

HENRY S. JA'UDON, Primary Examiner.

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