US3528459A - Loom - Google Patents

Description

Sept. 15, 1970 E.'PFARRWALLER ETAL 3,528,459

LOOM

Filed April 24, 1968 7 Sheets-Sheet 1 Fig. 1

119 F g 2 89a 30 122 85 Inventors. ERWIN PFARRWALLER GERD- SCHMITZ BY Winin J We M A TORNEYS Sept. 15, 1970 p w LL ET AL 3,528,459

7 LOOM Filed April 24, 1968 7 Sheets-Sheet 2 Inventors. ERWIN PFARRWALLER GERD SCHMITZ ATTORNEYS Sept. 15, 1970 p RRw iq ET AL 3,528,459

LOOM

Filed April 24, 1968 R E M W L F 1 M M O M T Vm n C A I W S 1 WW R E B E G 7 Sept. 15, 1970 F WA ET AL 3,528,459

LOOM

7 Sheets-Sheet 5 Filed April 24. 1968 ERWIN PFARRWALLER GERD SCHMITZ BYfiw J A TORNEYS Sept. 15, 1970 E. PFARRWALLER ET AL LOOM 7 Sheets-Sheet 6 Filed April 24, 1968 S L Y w R H M m WWW T mPS mow A. MN

Mm ma 5.

Sept. 15, 1970 Filed April 24. 1968 E. PFARRWALLER ET AL LOOM 5 Fig.1.? 2 a, a 1% a a 7 SheeCsSheet v Inventors.

ERWIN PFARRWALLER GERD SCHMITZ BY W, M11 may/J21,

A TORNEYS United States Patent 3,528,459 LOOM Erwin Pfarrwaller and Gerd Schmitz, Winterthur, Switzerland, assignors to Sulzer Brothers Limited, Winterthur, Switzerland, 21 Swiss company Filed Apr. 24, 1968, Ser. No. 723,684 Claims priority, application Switzerland, Apr. 27, 1967, 6,043/67 Int. Cl. D03d 47/38 U.S. Cl. 139-122 2 Claims ABSTRACT OF THE DISCLOSURE A loom employing a Jacquard mechanism for shedding and for weft-changing. Each of one or more weft-changing Jacquard cords serves, when pulled, or when released, to rotate a lever against a spring and thereby to store a weftchanging signal in the stress of that spring, which is engageable with a lifting-plate. The plate can be driven up or down, according to the angular position imposed on it by action of the spring when the plate is freed from a detent, in response to a cyclical rocking motion of two lifting-blades moving in opposite phases at the picking rate. The vertical motion of the lifting-plate, up or down from a neutral intermediate position, stores energy in a power spring for subsequent quick actuation of the weftchanging mechanism in one direction or the other when the weft-changing mechanism is released. The motion of the weft-changing mechanism and hence the selection of the weft can be composed of motions produced by plural such power springs due to the action of separate liftingplates.

The present invention relates to a loom having a Jacquard mechanism for controlling the shedding of the weft threads and having a weft-changing mechanism for changing the wefts which are to be picked. A Weftchanging mechanism changes the Weft to be picked so that wefts of various types (e.g. of various colors or of various materials) can be picked into the shed according to a program. It will be assumed hereinafter, but only by way of example, that wefts of various colors are being changed in a multi-color loom.

In a loom of the type described which has already been proposed the Jacquard machine is used solely to control the warp threads, and the weft-changing mechanism is controlled by a separate control device, e.g. a card dobby, containing on a punched card the program of the color sequence for the wefts which are to be picked. In this known construction the loom does not contain heddle frames for the warp threads, since the latter are controlled by the Jacquard mechanism. The card dobbyvis used solely to control the weft-changing mechanism.

It is an object of the invention to provide an improved and simplified weft-changing mechanism.

According to the invention, the loom has a weftchanging mechanism for changing the wefts to be picked and a Jacquard mechanism operatively connectedlo control the shedding of the warp threads and also to control the operation of the weft-changing mechanism.

With such a loom, it is not necessary to have a separate control device such as a card dobby for the weft-changing mechanism. The Jacquard mechanism is used to control both the warp threads and the weft-changing mechanism.

In one preferred construction, the operative connection between the Jacquard mechanism and the weftchanging mechanism contains at least one force or energy storage device arranged to store temporarily the energy supplied by the Jacquard mechanism, representative of a weft-changing signal. This permits a movement originating in the Jacquard mechanism, and which may occur only 3,528,459 Patented Sept. 15., 1970 ice at a particular phase in each working cycle and which must always finish before the change of shed, to be used directly or indirectly for switching the weft-changing mechanism, an operation which must take place much faster than the shed-changing movement and at a different time in the cycle. The energy supplied by the Jacquard mechanism, or part of that energy, can be stored in the energy storage device and is available for the later fast operation of shifting the weft-changing mechanism to another =weft supply.

According to one presently preferred embodiment of the invention the operative connection or coupling between the signal energy storage device and the weftchanging mechanism includes a source of power, such as a mechanically driven crank or eccentric, and one or more drive energy storage devices which store energy delivered thereto by this source of power and which deliver that energy to operate the weft-changing mechanism. The signal energy storage device, driven by the Jacquard mechanism, can then be of small dimensions and of small storage capacity, so as to be readily operable by means of the J acquard machine itself, for example via Jacquard cords. The substantially greater force needed for fast shifting of the weft-changing mechanism can then be provided by the power drive and can be delivered to the weft-changing mechanism via the drive energy storage device, which can be designed for the large forces supplied by the power drive. In this way power is obtained for very rapid shifting of the weft-changing mechanism so that little time is required for weft-changing within a loom cycle.

In one presently preferred embodiment of the invention there is provided at least one lifting-plate coupled to a signal energy storage device which is caused to engage and disengage under control of the Jacquard program with suitable elements of the power drive train leading to the weft-changing mechanism. The loom may include stop means, cyclically movable in synchronism with the loom cycle, into and out of position engaging the lifting-plate, so as to stop the latter during the process of energy storage in the signal energy storage device. The energy thus delivered by the Jacquard mechanism, and stored, can then be used at a later phase of the loom cycle to quickly shift the lifting-plate into a position to be engaged by a lifting-blade as a step in the Weft-changing process.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be further described in terms of a non-limitative exemplary embodiment and by reference to the accompanying drawings in which:

FIG. 1 is a diagrammatic front elevational view of a loom according to the invention, seen from the cloth end;

FIG. 2 is a plan view on the line 11-11 in FIG. 1;

FIG. 3 is a perspective view of the main parts of the weft-changing mechanism of the loom of FIG. 1;

FIGS. 4 and 5 are detail sectional views of the energy storage device 31 of the weft-changing mechanism of FIG. 3, shown in two different positions;-

FIG. 6 is a diagram showing four positions for the weftchanging mechanism shown in FIG. 3;

FIG. 7 is a view in side elevation of the lifting-plate 91 of FIG. 3, shown in a first position with certain associated elements of structure;

FIG. 8 is a fragmentary sectional view taken on the line VIlI--VIII in FIG. 7;

FIG. 9 is a sectional view taken on the line IXIX in FIG. 7, but including further parts not shown in FIG. 7;

FIG. 10 is a side view of part of FIG. 9, seen from the right in FIG. 9;

FIG. 11 is a side elevation of the lifting-plate 91 of FIG. 3, together with a part of the associated mechanism, the plate being shown however in an angular position different from that occupied by it in FIG. 7;

FIG. 12 is a further side elevation similar to that of FIG. 7, but showing the plate 91 in lifted position; and

FIGS. 13A through 13H are curves illustrating motions of various parts of the weft-changing mechanism.

FIG. 14 is a plan view of some details of FIGS. 7 and 11.

DESCRIPTION OF PREFERRED EMBODIMENTS In FIG. 1, the loom has a base wtih two uprights 1 and'2 between which there are a warp beam 50, a cloth beam 3 with the cloth web 4 wound onto it, guide and tension means (not shown) for the warps 22 and cloth 4, and a main drive shaft 5. Outside the upright 1 there is a coupling 6 with a brake and an electric drive motor 7. Alternatively, the coupling, brake and motor may be on the right side in FIG. 1. FIG. 1 also shows a reed 8 for beating up the weft 10 and, above the loom, a Jacquard mechanism with pull cords 26 passing through a hardness board 40, to form the shed with the warps 22. One or more pull cords 85 (two, in the embodiment illustrated) extend from the Jacquard mechanism to control a weft-changing mechanism (in the present case a four-weft mechanism) generally designated at 86 in FIG. 1.

The loom has a bobbin support 87 with screens 88 for limiting the balloon of the yarn. Between the screens there are weft supply bobbins 89a and 89d. During weaving, weft is drawn from the bobbins in turn and picked into the shed, as indicated at 10 in FIG. 1, by gripper shuttles 12 running in a shuttle guide 14. The appropriate weft color, according to the weft thread program, is selected by the four-weft mechanism 86 and is passed to the shuttle 12 by means which will be described below. The shuttle 12 is picked by a picking motion 13 and runs to a catching motion 15. A selvage tuck-in device 16 is provided at each edge of the cloth, in addition to the motions 13, 15. Each. device 16 contains a centering device for centering the weft picked, a thread clamp for clamping the weft, and-on the picking side--a cutting device to sever the weft. Each tuck-in device 16 also includes a tuck-in needle which tucks the free weft end into the next shed, forming a selvage at the edge of the cloth.

The four-weft mechanism 86 contains two lifting-plates 91 and 92 (FIG. 3) which can move up and down and which will be described in detail below. The plates 91 and 92 constitute separate weft selecting members. They are pivoted at 93 to bell-crank levers 28 and 29 rotatable about stationary pivots 25. At 94 the bell-crank levers are also pivotally conected to weft-changing drive energy storage devices 30 and 31 to be further described below. The storage devices 30, 31 contain springs adapted to move rods 32 and 33. These rods are pivoted to arms 95 of three- arm levers 36 and 37 rotatable about stationary pivots 34. Arms 38 and 39 of the three-arm levers are pivotally connected by pins 40 and 41 to the ends 42 and 43 of a balance lever 35. A link is pivoted to the balance lever 35 at a point 44 which forms a fulcrum for the lever, and the link 45 is also pivoted to a crank arm 46, to whose crank shaft 47 a weft changing drum 21 is attached.

Four shuttle feeders 49a to 49d are adapted to slide in grooves 48a to 48d in the selector drum. A device (not shown) shifts them as required towards the shuttle 12 when they are in the picking line.

Four notches or recesses 52a to 52d are provided in the rear of the drum 21 to accommodate a locking roller 53. This roller is mounted on a lever 54 rotatable about a stationary pivot 55. A rod 56 pivoted to the lever 54 carries a pin 57, which engages a control groove 58 in a disc cam 59. This cam is attached to a shaft 61 operated at a speed equal to the picking speed of the loom, i.e. shaft 61 rotates once per picking cycle.

The two weft-changing drive energy storage devices 30 and 31 are identical. Storage device 31 will now be described in detail with reference to FIGS. 4 and 5. A

compression spring 67 is supported in a cylindrical casing 65 between two movable spring guides 68 and 69, through which passes a rod 33. The casing 65 is pivoted at 94 to the bell-crank lever 29, and the rod 33 is hinged at its eye 71 to the three-armed lever 37. The rod 33 can slide in a bore in the casing 65. Two shoulders 73 and 72 are provided on the rod against which the spring guides 68 and 69 respectively can bear. These guides are in two parts, so that they can be fastened about the thinner portion 33a of the rod, between shoulders 72 and 73. The two portions of each guide are held together by an end coil of the spring 67.

In the pulled-out position shown in FIG. 4, the rod 33 is pulled downwards and outwards relative to the casing 65, so that the spring 67 is compressed downwardly by the guide 68, forced away from the upper portion 65a of the casing by action of the shoulder 73. There are equal gaps S between the upper portion 65a and shoulder 73 (i.e. guide 68) and between the guide 69 and the shoulder 72. The spring 67 tends to move the rod 33 relative to the casing 65 until the gaps S disappear. For example, the rod 33 may be moved upwards in FIG. 4 by the spring, or the casing 65 may be moved downwards, or the rod and the casing may both be moved towards each other. When S is zero, the force storage means 31 is in a central, inoperative or rest position, in which there is not net force tending to shift the relative position of the rod 33 and casing 65.

In the oppositely stressed position in FIG. 5, the rod 33 has been pushed upwards relative to the casing 65, causing equal gaps 5' between the guide 69 or shoulder 72 and the lower portion 65b of the casing, and between the shoulder 73 and the guide 68. The gap S of FIG. 5 is shown as equal to the gap S in FIG. 4. In the position shown in FIG. 5, the spring tends to move the rod 33 in the direction relative to the casing 65 opposite from that in FIG. 4, toward the central rest position. Obviously the position of minimum strain for the spring is that in which the guides 68 and 69 are both seated on their respective casing portions 64a and 65b, in which event the shoulders 73 and 72 are flush with those casing portions. In the inoperative central position, S is zero. By pulling on the two ends 64 and 71 of the storage devices 30 and 31 apart or by pressing them together, these devices (hereinafter sometimes called spring cylinders) can therefore be brought out of their inoperative central position into an energy storage position, from which they tend to return to the inoperative central position The devices 39 and 31 thus constitute extensible and compressible drive spring elements.

Referring again to FIG. 3, damping pistons 78 and 79 are pivoted on arms 76 and 77 of the three- armed levers 36 and 37. These pistons move in cylinders and 81 containing damping fluid, e.g. oil. As the pistons rise or fall, they retard the pivoting movement of the levers 36 and 37 and therefore the weft-changing movement of the drum 21, particularly in the latter stages of any movement. The top and bottom ends of the cylinders 80 and 81 form stops for the pistons therein.

Each of the two levers 36 and 37 can take up either of two positions, depending on the switching movements of its corresponding one of the cylinders 30 and 31. To these two positions there correspond the upper and lower positions of pistons 78 and 79. Since the distances of the fulcrum 44 on the balance lever 35 from the ends 42 and 43 of this lever are in the proportion of 1:2, four positions 35a to 35d are possible for this lever, as shown in FIG. 6. Any two adjacent ones of the positions a to d of the fulcrum are at equal distances from one another. In FIG. 6 there are shown the four positions a to d of the fulcrum 44, with the corresponding positions 21a to 21d of the weft selector drum 21 diagrammatically indicated in association therewith.

In FIG. 3, the two pistons 78 and 79 are in their upper positions. The cylinder 30 is in the compressed condition illustrated in FIG. for cylinder 31, with spring 67 of cylinder 30 compressed by forcing of rod 32 into the casing beyond the equilibrium point. Consequently, the cylinder 30 tends to rotate the lever 36 clockwise as seen in FIG. 3. Cylinder 31 is in its pulled-out position as illustrated for it in FIG. 4, and therefore tends torotate the lever 37 anticlockwise. In FIG. 3, both of these motions have however already proceeded as far as posisible, the upper limit of travel of piston 78 limiting clockwise travel of lever 36 while the upper limit of travel of piston 79 limits counterclockwise travel of lever 37. The pins 40 and '41 are thus both in their lowest positions, so that the balance lever 35 is in position 35d (FIG. 6) and the drum 21 is in the position 21d shown on the left in FIG. 6. The shuttle feeder 49d is therefore in the picking line, and the locking roller 53 has entered the recess 52d to lock the weft selector drum 21, all as illustrated in FIG. 3.

The two lifting- plates 91 and 92 are identical, and their driving members are also identical. Lifting-plate 91 and the associated driving members will now be described in detail with reference to FIG. 7. The plate contains an aperture 101 the periphery of which includes four portions 1014 to 101d which may be substantially vertical, an arcuate portion 101e lying between portions 101a and 101b, and an arcuate portion 101 lying between the portions 101a and 101d.

Two lifting- blades 102 and 103 pass through the apertures 101 in both of plates 91 and 92. The blade 102 is mounted in one arm 104 of a lever 104, 107 and the blade 103 is mounted in one arm 105 of a lever 105, 108. These levers are pivotable on a stationary pivot 106. The arms 107 and 108 of these levers are engaged by driving levers 109 and 111, operated by eccentrics 113 and 114 mounted on a rotatable but non-translational shaft 112. The shaft 112 rotates at the same speed as the loom main shaft so that each of the lifting- blades 102 and 103 carries out one upward and one downward movement per cycle and therefore per pick. These motions are indicated by the arrows 115 in FIG. 7. The strokes of the two lifting-blades are equal, but the range over which the blade 102 moves is somewhat above that over which the blade 103 moves. The blade 102 may engage portion 101e, as shown in FIG. 7, or blade 103 may engage portion 101 as shown in FIG. 12, depending on the position of the plate 91, further described below. The blade 102 can move the plate 91 downwards while the blade 103 can move it upwards. The blades 102 and 103 constitute drive means engageable with the weft selecting members 91 and 92 to effect motion of those members upwardly and downwardly (as seen in FIG. 12) according to the position of those members about their pivots 93.

The rods 33 of two further energy storing spring cylinders 115 are pivotally connected each at 116 to the uppermost end of a separate one of the lifting- plates 91 and 92. Each of the cylinders 115 is of the same construction as the cylinders 30 and 31 shown in FIGS. 3 to 5, except that for each an arm 118 of a control lever having three arms 118, 121 and 122, movable about a stationary pivot 119, is hinged to the central portion of the casing 65 of the cylinder 115 by means of a needle bearing 117 (FIG. 8). Also, the cylinders 115 have substantially weaker springs than the springs 67 of cylinders 30 and 31. The cylinders 115 thus constitute extensible and compressible signal spring elements. On each of the threearm control levers the end 123 of the arm 121 is engaged by a pin 124, to which a spring guide 125 is attached. A compression spring 127 is supported between the guide 125 and a fixed portion 126 of the loom frame. Portion 126 carries a guide 128 for the spring 127. The springs 127 tend to rotate the two control levers 118, 121, 122 anticlockwise as seen in FIG. 7. A harness cord 85, looped on to the relatively long arm '122 of each of these levers can rotate the control levers 118, 121, 122

6 clockwise about the pivot 119 when pulled by the lacquard mechanism 20 (FIG. 1).

Each of the lifting-plates 91 and 92 (FIGS. 7, 9) has at the bottom a projection 131 having arcuate edges 132 and 133. A sleeve 135 (FIG 9) is attached to a fixed portion 134 of the loom base and contains a movable rod 136. At the left end as seen in FIG. 9 this rod bears a stop pin 137. A transverse bar 141, connected to the rod 136 by a screw 139, is slidably mounted in slots 138 at the right-hand end of the sleeve 135. The bar carries a roller 143 cooperating with a face cam 142. This cam is operated at the same speed as the loom main shaft, so that the pin or detent 137 takes up the inoperative position shown in solid lines in FIG. 9 once per cycle (on account of the raised portion 142a 0f the cam) and reaches the stop position 137a shown in broken lines under the influence of a compression spring 144 when the roller 141 moves on to the low portion 142b of the cam. In this position the lifting- plates 91 and 92 are prevented from rotating about their pivots 93. The stop pin 137 may act either on the edge 132 (FIG. 7) or on the edge 133 (FIG. 12) of each of the plates 91 and 92. With the two plates in different positions, the stop 137 may be at the edge 132 of one plate and the edge 133 of the other.

In the curves of FIGS. 13A to 13H, the angular positions of the loom main shaft are plotted on the abscissae. FIG. 13A illustrates the vertical movement of the harness cords 26 and and therfore of the warp threads. FIG. 13B shows the movement of the lifting-blade 102 and FIG. 130 shows that of the lifting-blade 103. In FIG. 13D the solid and dash line curves show the vertical movement of the lifting plates 91 and 92 respectively, caused by the lifting-blades. FIG. 13E shows the backward and forward pivoting of the plates 91 and 92 about their pivots 93 caused by the harness cords 85. FIG. 13F shows the movement of the stop 137. FIG. 13G shows the movement of the locking rollers 53, and FIG. 13H shows the movement of the weft selector drum 21.

The mode of operation of the apparatus is as follows:

When the main loom shaft is in a selected position, assumed to be zero degrees on the scale of abscissae in FIG. 13, the Jacquard cords 26 to the warp heddles and 85 to the weft-changing mechanism are in an intermediate position denoted J in FIG. 13A, corresponding to the closed position of the shed. With counterclockwise rotation of lever 28, as seen in FIGS. 7, 11 and 12, and with extended, pulled-out position for the spring cylinder 30' as shown in FIG. 4, the blade 102 moves downwardly as at K in FIG. 13B while blade 103 in contrast moves upwardly as indicated at L in FIG. 13C. When plate 91 is counterclockwise as shown in FIG. 7 and as indicated by the lower flat part M of the full-line angular position curve in FIG. 13E, it will be engaged at notch 101e by the downwardly moving blade 102 as indicated at N in FIG. 13D. Plate 91 being counterclockwise, blade 103 cannot engage it. Since however plate 92 is clockwise, as indicated by the initial upper flat portion of the dash-line curve in FIG. 13E, blade 103 can engage with plate 92 so as to move plate 92 upwardly, as indicated at N on the dash-line curve in FIG. 13D. Over the upper flat portion P of FIG. 13F, the stop pin 137 is in operative position, holding plate 91 in counterclockwise position and plate 92 in clockwise position. The blocking roller 53 is engaged with drum 21 over the flat lower portion Q of FIG. 13G. The weft-changing drum 21 will be locked, over phase R in FIG. 13H, for example in the locked position 21d shown in FIGS. 3 and 6.

With further upward motion beyond I of the Jacquard cord 85 pertaining to plate 91, the lever generally indicated at 118 to which that cord is attached is rotated about its axis 119 in the clockwise sense in the vicinity of the phase S of FIG. 13A. This rotation requires compression of spring cylinder 115, spring cylinder being shifted to the right, so that that cylinder is transferred from the neutral or rest position to the compressed stressed or energy-storing position illustrated in FIG. for the similar cylinder 31. This compression is preparatory to clockwise rotation of the plate 91 about its pivot 93.

At approximately 50 past zero degrees in the loom cycle, i.e. at the phase S in FIG. 13A and T in FIG. 13F, there begins withdrawal of the stop pin 137 from its operative position 137a. The pin is completely withdrawn at phase U in FIG. 13F, 90 after the start of the loom cycle. When the blade 102 reaches its lowest position, shown in FIG. 7, at 70 of the loom cycle (phase V in FIG. 13B) and when simultaneously the blade 103 has reached its highest position, the locking roller 53 has completed withdrawal from drum 21, as indicated at W in FIG. 13G. Consequently, the energy stored in cylinder 30 upon the downward motion of plate 91 and consequent counterclockwise rotation of lever 28, now completed, can become effective to rotate lever 36 counterclockwise in FIG. 3. The weft-changing drum 21 shifts quickly at phase X in FIG. 13H from the position 21d to another position, for example the position 21a on the assumption that blade 92 had been rocked clockwise so as to be lifted by blade 103. Immediately thereupon the locking roller 53 returns to locking position as indicated by the middle lower portion of FIG. 13G. At 105 of the loom cycle, the picking operation may begin. The above-described storage of energy in cylinder 115 is employed only for the second next pick.

When the blade 102 is again moved upwardly at about the phase Y of FIG. 13B, the plate 91 will follow upwards a short distance, as indicated at Z in FIG. 13D, in consequence of a residual stressing of the spring in cylinder 30 even after the counterclockwise rotation permitted to lever 36 when drum 21 was unlocked. A neutral intermediate position for the cylinder 30 is reached at 125 of the loom cycle, indicated at phase g in FIG. 13D, and upward movement of plate 91 stops. Upon further upward motion of the blade 102, this blade will be withdrawn from the arcuate portion 1012 of the opening 101 so that the plate 91 can, at phase h of FIG. 13E, be rotated clockwise about its axis 93 under influence of the energy now stored in the cylinder 115. A first portion of the rocking motion extends to phase i. Here the portion 1010 of the boundary of the cut-out 101 comes into engagement with the blade 103 now moved approximately halfway along its downward path of motion. It is only upon further downward motion of the blade 103, occurring at the phase k in FIG. 13E, that the blade 103 comes into position below the arc 1011 of the cut-out 101. Therewith, the plate 91 is rotated through a second are about its axis 93 in the clockwise direction under influence of the cylinder 115, this motion ending at the phase m in FIG. 13E. The position of the plate 91 shown in FIG. 11 has now been reached. In this position the blade 103 is in its lowest position, whereas the blade 102 is in its highest position. These are the positions shown for the blades in FIG. 11. For comparison, these two extreme positions for the blades have been shown in dash-lines in FIG. 7. At some 230 of the loom cycle, indicated at phase 11 in FIG. 13F, there begins motion of the stop pin 137 into its elfective position 137a, reached at 270 of the loom cycle as indicated at p in FIG. 13F. Plate 91 is thereby held fast in the clockwise angular position therefor about its axis 93 shown in FIG. 11.

The blade 102 has reached its uppermost position, shown for it in FIG. 11, at phase q in FIG. 133 while blade 103 has reached its lowest position at phase r in FIG. 13C. Thereupon the blades 102 and 103 move respectively downwardly and upwardly, at the phases s and t in FIGS. 13B and 13C respectively, but without effect on the position of plate 91. The rising blade 103 engages the are 101] of blade 91 at phase u of FIG. 13D. The blade 102 may or may not simultaneously come into contact with the plate 92 at its arc 101e, depending on the angular position of plate 92. In this way, at phase v the plate 91 will be moved upwardly so that at of the next loom cycle, i.e. the phase w and y of FIGS. 13C and 13D, the energy storage cylinder 30 will have been shifted to its opposite extreme or compressed position. In the now immediately following disengagement of the locking roller 53 which occurs at the phase 150 of FIG. 13G, the weft-changing drum 21 will move, at phase 151, from its position 21a to another position, for example the position 210 (FIG. 13H), under influence of the energy stored in the spring of the cylinder 30. The elements of structure have now been brought into the position illustrated in FIG. 12.

When the cord is allowed to descend at phase 152 of FIG. 13A, the switching or control lever 118 is rotated in counterclockwise sense about its axis 119, as seen in FIG. 12, by operation of the spring 127. In this process the storage cylinder 115 is pulled out or extended, and returns to the opposite condition of energy storage, i.e. the pulledout position, initially occupied by it. This constitutes preparation for counterclockwise rotation of plate 91 about its axis 93.

As soon as the stop pin 137 has been withdrawn at the phase 153 of FIG. 13F, the lifting-plate 91 is rocked counterclockwise in two steps about its axis 93 at the phase 154 of FIG. 13E by operation of the cylinder 115. The plate 91 is now positioned to be entrained by the blade 102 at the arc 1012 of the cut-out 101 upon the next downward motion of that blade. The cylinder 30 is again shifted into the pulled-out stressed position, and the drum 21 shifts immediately to a new position when the locking cylinder 53 is withdrawn. The elements then have returned to the position shown in FIG. 7.

The dash-line curves in FIGS. 13A, D and E represent possible courses for the position of the Jacquard cord 85, for the vertical position of plate 92, and for the angular position of plate 92 respectively, all opposite in phase to the position shown by the full-line curves in those figures. The motions of the plate 92 and of its controlling cord may however be the same as and in phase with those of the plate 91.

The dash-line curve in FIG. 13H illustrates other possible motions for the weft-changing drum, from position 21a to position 21d and thereafter from position 21d to position 21b. Insertion of the shuttle begins for example at of the loom cycle when the shed has almost reached open position and the cords 26 have almost ceased their motion. Consequently the cords 85 cannot now either be used for storage of energy in the cylinder 115, any more than the cords 26. This energy must therefore have been stored at the phases J and S in FIG. 13A, at which times the cords 85 are in motion. It is only at these times that these cords can be moved.

The blades 102 and 103 together with the elements 104 to 109, 111, 113 and 114 constitute a drive train through which the relatively large forces required for setting the drive cylinders 30 and 31 can be brought to bear. Setting is here used to refer to the stressing of the springs in those cylinders with consequent storage of energy therein. The strong springs of the cylinders 30 and 31 are required for a sufiiciently rapid change of the weft-changing drum. The forces necessary thus to set the cylinders 30 and 31 are derived from the blades 102 and 103 via the plates 91 and 92. Control of the plates, i.e. guidance thereof to the positions in which they can come into engagement with one or the other of the blades, is effected by the storage cylinders 115 of those plates respectively. The relatively small force required to set the signal cylinders 115 can be delivered through the Jacquard cords 85 with the aid of the forcemultiplying levers 118.

Whereas in any case two blades 102 and 103 are neces sary, two plates 91 and 92 are required for four-color (four weft) operation (as in the embodiment described), and three plates are required when selection is to be made among six wefts. Only one plate is necessary for selection among two wefts. To each plate provided there is coupled a switching or drive mechanism comprising a lever such as the lever 28, a drive cylinder such as the cylinder 30 and elements '102, 103, 113 and 114 of the drive, and a signal or control mechanism comprising elements 115, 118 and 85.

In a modified form of construction it is possible to forego the power drive of elements 102 to 114 and to couple the cylinders 115 and their pins 33 directly to the arms 95 of the recited levers 36 and 37. This construction is particularly to be recommended when the force available from the cords 85 for setting the cylinders 115, though none too great, is sufficient to switch the drum 21. Such a construction is advantageous when the weft-changing drum is required to execute only relatively slow changes among a small number of wefts, such as two. The force multiplication obtained by proportioning of the arms of lever 118 can moreover be so dimensioned as to avoid overstressing the cord in an embodiment without power drive.

If however a quick and sudden motion of the drum 21 is to be achieved, for, example if selection is to be made among as many as four or six Weft colors, or if the loom operates at a high picking rate, then the power cylinders 30 and 31 and the appurtenant drive must be provided.

FIG. 2 illustrates a compact form of construction in which the shafts 119 and 25 are combined, the control levers 118 and switching levers 28 being pivoted about that axis.

The invention can also be employed with looms employing other types of picking mechanism such as gripper needles, or air or water-stream picking systems. In such embodiments the drum 21 may be modified into a suitable weft-changing element.

While the invention has been described hereinabove in terms of a presently preferred embodiment thereof, the invention is not limited thereto but comprehends all modification of and departues from the embodiments so described properly falling within the spirit and scope of the appended claims.

We claim:

1. A loom comprising a Jacquard mechanism, warp shedding means under control of said mechanism, weft picking means, plural position weft changing means, a weft selecting member movable in opposite first directions and movable in opposite second directions, an extensible and compressible signal spring element coupled between the Jacquard mechanism and Weft selecting member for motion of the latter in said first directions in response to motions of the Jacquard mechanism, an extensible and compressible drive spring elment coupled between said member anl weft changing means for motion of the latter in response to motions of the member in said second directions, and drive means engageable with said member for motion of the latter in said second opposite directions according to the position of said member along said opposite first directions.

-2. A loom comprising a drive, a Jacquard mechanism, warp shedding means under control of said mechanism, weft picking means, releasably lockable plural-position means to support a plurality of weft feeders, an extensible and compressible signal spring element under control of the Jacquard mechanism, an extensible and compressible drive spring element having two ends coupled at one end to said support means, two reciprocable lifting-blades movable cyclically in opposite phases under control of said drive, a lifting-plate coupled to the other end of said drive spring element for opposite extensions thereof in response to movements of the lifting-plate in opposite first directions, said plate being reversibly movable in opposite second directions under influence of said signal spring element between two positions in each of which a separate one of said lifting-blades drives said plate in an opposite one of said first directions, and stop means cyclically movable under influence of said drive to limit motion of said plate in said second directions to selected phases of the loom cycle.

References Cited UNITED STATES PATENTS 159,6 5 3 2/l 87'5 Dornan. 2,123,561 7/1938 Bond 139-171 2,490,589 12/1949 Gage et a1. 139171 3,111,144 11/19'63 Pfarrawaller 189-426 FOREIGN PATENTS 1,480,838 4/ 1967 France.

HENRY S. JAUDON, Primary Examiner U.S. Cl. XJR- 139-126

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