Shed mechanism for a weaving machine
United States Patent (1 1 Kallmeyer et al.  
  SHED MECHANISM FOR A WEAVING MACHINE I75} Inventors: Albert W. Kallmeyer, Crestwood;  
 Harry A. Holman, .lr., Ladue; William W. Weaver, St. Louis, all of Mo.  
 [73] Assignee: McDonnell Douglas Corporation. St. Louis, Mo.  
 [22] Filed: Oct. 13, 1972 [21] Appl. No.: 297,320  
 Primary l&#39;..ramiiwrStephen C. Bentley Attorney, Agent, or FirmGravc1y. Lieder &amp; Woodruff I571 ABSTRACT A circular weaving machine in which longitudinal 1 Apr. 8, 1975 threads are arranged in radial groups is provided with a shed mechanism for creating shed openings in the radial groups so that a wrap thread can be passed through the openings to produce a circular weave. The shed mechanism includes operating threads connected with the longitudinal threads and arranged in corresponding groups. The operating threads of each group extend outwardly from the longitudinal threads and thence downwardly. and suspended from the depending portions of the operating threads are gripping balls. A draw bar positioned below the gripping balls carries a pick-up assembly and indexing assembly for incrementally advancing the pick-up assembly. The pick-up assembly moves in the direction in which the group of balls is arranged, and as it does it either engages or disengages the gripping balls of the group. depending on the direction of movement. When a selected number of gripping balls are engaged or disengaged. a drive assembly lowers the draw bar and this pulls the operating threads connected with the engaged gripping balls downwardly. The displaced operating threads in turn draw the longitudinal threads to which they are connected outwardly to create a shed opening in the group of longitudinal threads.  
 14 Claims, 9 Drawing Figures PATENTEUMR 8i975 3.875873 sum 1 or 5 PATENIED AFR 8975 I Ill/l &#39;IWQVIIIIIIA SHED MECHANISM FOR A WEAVING MACHINE BACKGROUND OF THE INVENTION This invention relates in general to weaving machines and more particularly to a mechanism for producing a shed opening in the longitudinal threads on such machines.  
  Structural and ablative members have heretofore been produced by weaving yarn into a tubular configuration, impregnating the weave with a resin, and then curing the resin. The members so formed are characterized by high strength and light weight. Indeed, the strength of such materials approaches that of steel.  
  In order to provide adequate strength the weave must have substantial thickness. This is achieved by arranging the longitudinally extending threads ofthe weave in radial groups and then passing a wrap or weft thread through the longitudinal threads of each group. in which case the wrap thread will trace a curvilinear path. Few machines exist which have the capability of producing a circular weave of substantial thickness, much less automatically controlling the weave pattern. Indeed. controlling the weave pattern where the radial threads of each group are many in number has been a major problem in the art of circular weaving.  
 SUMMARY OF THE INVENTION One os the principal objects of the present invention is to provide a weaving machine with a mechanism for automatically varying the weave pattern. Another object is to provide a mechanism of the type described which is ideally suited for use with circular weaving machines wherein the longitudinal threads are arranged in radial groups. A further object is to provide a mechanism of the type stated which is suitable for use in circular weaving machines having the many threads in each radial group. These and other objects and advantages will become apparent hereinafter.  
  The present invention is embodied in a shed mechanism which creates a shed opening in a group of longitudinal threads. The device includes connectors engaged with the longitudinal threads. pick-up means for engaging a selected number of connectors, selector means for varying the number of connectors engaged by the pick-up means. and drive means for moving the pick-up means such that the connectors engaged by the pick-up means shift. The invention also consists in the parts and in the arrangements and combinations of parts hereinafter described and claimed.  
 DESCRIPTION OF THE DRAWINGS In the accompanying drawings which form part of the specification and wherein like numerals and letters refer to like parts wherever they occur:  
  FIG. I is a fragmentary elevational view in section of a weaving machine having shed mechanisms constructed in accordance with and embodying the present invention;  
  FIG. 2 is a fragmentary sectional view of a circular weave produced on the weaving machine;  
  FIG. 3 is an elevational view ofone ofthe shed mech anisms on the weaving machine;  
  FIG. 4 is a fragmentary elevational view of the shed mechanism and showing the draw bar thereof partially broken away;  
  FIG. 5 is a sectional view taken along line 55 of FIG. 4;  
  FIG. 6 is an enlarged elevational view of an indexing mechanism forming part of the shed mechanism;  
  FIG. 7 is a sectional view taken along line 77 of FIG. 6;  
  FIG. 8 is a fragmentary sectional view taken along line 88 of FIG. 7 but showing the whole of the indexing mechanism in its drive position; and  
  FIG. 9 is a sectional view taken along line 9-9 of FIG. 3.  
 DETAILED DESCRIPTION Referring now to the drawings, M (FIG. 1 designates a weaving machine which weaves a wrap or weft thread a into longitudinal or warp threads b to form a tubular weave w (FIG. 2). Actually, the weave w is formed about a mandrel m which is supported by the machine M and the longitudinal threads b are arranged in radial groups g. Each group g contains a plurality of longitudinal threads b arranged radially with respect to one another so that the group g as a whole projects radially outwardly from the surface of the mandrel m. To simplify the discussion of this invention each group g is illustrated having only a few longitudinal threads I), but it should be understood that each group g may contain many more such threads. To produce the weave iv. the  
 machine M moves the longitudinal threads I) of each group g independently of one another in the radial direction. while passing the wrap thread a through the various groups. Space for passage of the wrap thread a is provided in each group g by separating two adjacent longitudinal threads b of the group g more than the remaining adjacent threads I; so as to create a shed opening 0 in the group g. The wrap thread a is delivered as close to the apex of the shed opening 0 as possible. By changing the position of the shed opening 0 with each pass of the wrap thread a. intricate and varied weaves w are produced.  
  The weaving machine M includes (FIG. I) a framework 2 of generally circular configuration and this framework is provided with a center pillar 4 and a centrally disposed mandrel mount 6 above the pillar 4. The mandrel mount 6 carries an elevating mechanism 8 to which the mandrel m is secured so that as the weave a is formed about the mandrel m, the mandrel in may be elevated. This enables the wrap thread a to be delivered into the longitudinal threads b at about the same elevation irrespective of the amount of weave w preceding the thread a. The upper ends ofthe longitudinal threads 19 are anchored in a trough of polyethylene glue which is also carried by the elevating mechanism 8 above the mandrel m.  
  As previously mentioned the longitudinal threads I) extend downwardly past the side face ofthe mandrel m. At its lower end each longitudinal thread b is spliced to a working thread 10 which forms a continuation of the longitudinal thread b. The working threads I0 in turn pass through apertured guide plates I2 which are sup ported on the center pillar 4. The apertures ofthe guide plates I2 are arranged in radially extending rows so as to position the working threads 10, and likewise the longitudinal threads 12 attached thereto in the radial groups g. Below the lower of the two guide plates 12 the working threads 10 are tied to weights 14 which maintain the working threads 10 and longitudinal threads h under a slight amount of tension. The lower ofthe two guide plates 12 is shiftable in a vertical direction and is raised as the weave w progresses. The shed opening within each group g of longitudinal threads b is created by drawing all of those threads 10 located to the outside of the desired location for the opening 0 outwardly, in which case the weights I4 on the displaced working threads 10 will rise slightly. but will still maintain those threads under tension. All of those longitudinal threads b and working threads 10 to the inside of the shed opening 0 are in the inshed&#34; position. and conversely all to the outside are in the &#34;out-shed position.  
  The weaving machine M further includes (FIG. 1) a circular track 20 which is mounted on the framework 2 below the mandrel m and also below the splice joints between longitudinal threads h and the working threads I0. The track 20 is concentric with respect to the mandrel m and is segmented by radial slots 22 which align with the radial groups g of working threads 10. Indeed. the working threads 10 will move into the slots 22 of the track 20 when shifted to their out-shed positions.  
  The circular track 20 supports a carriage 24 provided with an electric motor which drives the carriage 24 around the track 20. the motor being engaged with the track 20 through a rack and pinion arrangement. In addition. the carriage 24 carries a bobbin 26 of wrap thread a and a filament insertion device 28 which extends upwardly beyond the track 20 for delivering the wrap thread a from the bobbin 26 into the apex of the shed opening 0 as the carriage 24 moves along the track The weaving machine M is further provided with a shed mechanism for displacing the longitudinal threads b of each group g outwardly to form shed openings u in those groups g. and for also changing the positions of the shed openings 0. The shed mechanism S has five basic components for each group g of longitudinal threads 11 and working threads 10, namely. a draw as&#39; sembly 36 (FIGS. I and 3). a frame assembly 38 (FIG. 3] a pick-up assembly 40 (FIGS. 4 and 5 J. an indexing assembly 42 (FIGS. 6-8]. and a drive assembly 44 (FIG 3). The assemblies 36. 38, 40 and 42 are positionetl radially outwardly from the groups g of working threads with which they are associated.  
  The draw assembly 36 for each group g of longitudi nal threads I) and working threads 10 is actually en gaged with the working threads 10, serving as a connection between those threads and the pick-up assembly 40. The draw assembly 36 includes an operating thread 50 (FIG. I] for each working thread I0, and the operating threads 50 for each group g of working threads 10 are likewise arranged in a group g. Thus. for every group g of longitudinal threads I) and working threads I0 there is a group g of operating threads 50, and for every working thread [0 within a group g there is an operating thread 50 within the corresponding group g. Each operating thread 50 attaches to its corresponding working thread I0 below the circular track with the operating threads 50 for the innermost working threads 10 being below the operating threads 50 for the outermost working threads 10 insofar as each individual group g is concerned.  
  Considering now only one group g of operating threads 50, those threads extend outwardly to a positioning board 52 (FIG. I] having eyes 54 mounted thereon at equally spaced intervals and in a line canted 45 to the vertical. The lowermost eye 54 is disposed furthest inwardly and receives the operating thread 50 connected to the innermost working thread 10. The up permost eye 54 is disposed furthest outwardly and receives the operating thread connected with the outermost working thread 10. The intermediate eyes 54 receive the remaining operating threads 50 such that the operating threads extend outwardly from the working threads 10 and then downwardly without crossing one another. The operating threads 10 depend from the eyes 54 and since the eyes 54 are arranged in a line canted at 45, the operating thread 50 connected to the innermost working thread will be innermost. while the operating thread 50 connected to the outermost work ing thread 10 will be outermost. Since the eyes 54 are equally spaced, the spacing between the depending portions ofadjacent operating threads 50 will be equal.  
  Each operating thread 50 extends downwardly to a pulley 56 where it reverses direction, and extends upwardly to the outside edge of the positioning board 52. The upper ends of the threads 50 are fastened to the positioning board 52 by means of removeable anchor pegs 58 which fit into holes in the outer edge of the board 52. Thus, the height of an individual pulley 56 can be adjusted by removing the anchor peg 58 for the operating thread 50 extending through that pulley 56 and then raising or lowering the terminal end of the operating thread 50. This enables the operator to position all pulleys 56 at the same height. Each pulley 56 has an operaring wire 60 (FIGS. I and 3) depending from it. and each wire 60 is provided with a swaged gripping ball 62 at its lower end and a limit ball 64 located up wardly from the gripping ball 62. Each operating thread 50, the pulley 56 supported thereby. and the operating wire 60 and gripping ball 62 suspended from the pulley 56 are considered a connector with the inner end of the connector being that end of the thread 50 attached to the corresponding longitudinal working thread 10 and the opposite end being the gripping ball 62.  
  The frame assemblies 38 (FIGS. 3 and 4) are also mounted on the framework 2, with the frame assembly 38 for a particular group 3&#39; of operating threads 50 being located directly below the positioning board 52 for that group g so that the depending portions of the operating threads 50 align with the frame assembly 38, and the operating wires 60 connected to those threads 50 pass through it.  
  Each frame assembly 38 includes inner and outer vertical rods 68 which are bolted to the framework 2, and have vertical mounting plates 70 fastened to the upper portions of them. Interconnecting the vertical mounting plates 70 are pairs of channel-shaped guide plates 72 and 74. The guide plates 72 and 74 are disposed horizontally. and further extend radially with re spect to the center axis of the machine M. Moreover. the upper guide plates 72 are located below the pulleys 56 on the operating threads 50 and are spaced apart a distance slightly greater than the diameter of the operating wires 60. The same is true of the lower guide plates 74. Indeed. the operating wires 60 for the group g depend through the spaces between the guide plates 72 and 74 and immediately below the lower guide plates 74 are the limit balls 64 for the operating wires 60. The diameter of the limit balls 64 is greater than the spacing between the two lower guide plates 74 and con sequently the limit balls 64 prevent the wires 60 from being displaced upwardly. The two guide plates 72 and likewise the two guide plates 74 are provided with guide pins 76 (FIG. 4) which traverse the spaces he tween those plates and maintain the proper radial spacing between adjacent operating wires 60.  
  The two vertical rods 68 are further connected by a lower structural member 78 (FIG. 3) located near the bottom of the frame assembly 38 and considerably below the pair of lower guide plates 74.  
  Aside from the foregoing components, each frame assembly 38 is further provided with a draw bar 80 (FIGS. 3 and 4) which shifts vertically in the space between the lower guide plate 74 and the lower structural member 78. The draw bar 80 consists of a pair of side plates 82 which are separated at their lower edges by a track member 84 having a centrally disposed rib 85 extending the length thereof. Near their ends the side plates 82 are further separated by spacer blocks having grooved guide rollers 88 journaled in them. The rollers 88 at the peripheral grooves thereon engage the vertical rods 68 and guide the bar 80 as it moves upwardly and downwardly. Mounted within the interior of the draw bar 80 near the ends thereof are pairs of pulleys 90, and trained over these pulleys 90 are two stabilizing cables 92. One stabilizing cable 92 is secured to the lower structural member 78 adjacent to the inner vertical rod 68. From that point of securement it extends upwardly along the inner vertical rod 68 to the lower pulley 90 at the inner end of the draw bar 80, over which it is trained. The cable 92 thereupon extends through the interior of the bar 80 to the upper of the two pulleys 90 at the outside end of the bar 80. After passing around that pulley 90 the cable extends upwardly along the outer vertical rod 68 and is fastened to the mounting plate 70 located along that rod 68. The other cable 92 is connected to the lower structural member 78 at the outer end of that member. and passes over the lower of the two pulleys 90 at the outer end ofthe bar 80. It then extends through the interior of the bar 80 and passes around the upper pulley 90 at the inner end of the bar 80, beyond which it is secured to the mounting plate 70 on the inner vertical rod 68. The arrangement of pulleys 90 and cables 92 maintains the draw bar 80 perfectly horizontal as it moves vertically in the space between the lower guide plate 74 and the lower structural member 78.  
  Along their upper edges the side plates 82 of the draw bar 80 have inwardly directed rims 94 (FIGS. 4 and 5) and the distance between the two rims 94 exceeds the diameter of the gripping balls 62, thus enabling the gripping balls 62 and the lower ends of the operating wires 60 to fit into the interior of the draw bar 80 when the draw bar 80 is raised to its uppermost position.  
  The pick-up assembly 40 (FIGS. 4 and 5) is housed within the hollow interior ofthe draw bar 80, and is furthermore shiftable longitudinally of the draw bar 80. In other words. the pick-up assembly 40, shifts radially with respect to the central axis of the weaving machine M. The pick-up assembly 40 includes a slide bar 100 which rests on the central rib 85 of the track member 84 and slides relative thereto. Riveted to the slide bar 100 are a pair of upstanding plates 102 which are set inwardly from the side plate 82 of the draw bar 80. At their upper ends the upstanding plates 102 are fitted with low friction guide blocks 104 which project outwardly and are positioned immediately below the inwardly directed rims 94 on the side plates 82 of the draw bar 80. The guide blocks 104 bear against the inside faces of those side plates 82 and maintain the pickup assembly 40 centered with respect to the draw bar 80. They further prevent upward withdrawal of the pick-up assembly 40. The upstanding plates 102 are further provided with gripping strips 106 (FIG. 5) which project inwardly into space between the plates 102 at the upper ends thereof. The two gripping strips 106 are spaced apart a distance greater than the diam eter of the operating wires 60, but less than the diameter of the gripping balls 62 on the lower end of the operat ing wires 60. Moreover. the innermost end ofthe pickup assembly 40 is open, and when the draw bar is positioned in its uppermost position on the frame assembly 38. the shoulder at the lower ends of the gripping strips 106 is above the gripping balls 62 on the operating wires 60. Hence. when the pick-up assembly 40 is moved along the draw bar 80 toward the group g of operating wires 60 and gripping balls 62, the gripping balls 62 will in time enter the space between the upstanding plates 102 of the pick-up assembly 40. in which case the operating wires 60 will pass through the space between the gripping strips 106, assuming of course that the pick-up bar 80 is in its uppermost position. If the draw bar 80 moves downwardly. the gripping balls 62 will be engaged by the shoulder at the lower ends of the gripping strips 106 and displace downwardly also. This in turn will draw the operating wires 60 connected to the displaced gripping balls 62 downwardly. Of course, some of the gripping balls 62 within a group g may be engaged and some may not. the number engaged being dependent on the position of the pick-up assembly 40 within the draw bar 80.  
  Also riveted to the slide bar of the pick-up assembly 40 are ratchet bars 108 which project downwardly across the side faces of the rib 85, but do not en gage the top surface of the track member 84. The ratchet bars 108 have downwardly projecting ratchet teeth. with the spacing between these teeth being equal to the spacing between adjacent gripping balls 62. Moreover, the two bars 108 are oriented with their teeth projecting in opposite directions.  
  The indexing assembly 42 (FIGS. 68) fastens to the underside of the draw bar 80 and is engageable with the ratchet teeth on the ratchet bars 108 for displacing the pick-up assembly 40 in either direction along the bar 80. More specifically. the function of the indexing assembly 42 is to engage the ratchet bars 108 and effect a one pitch change in the position of the ratchet bar 108 so engaged and the pick-up assembly 40 connected thereto for every electrical pulse received by it.  
  The indexing assembly 42 includes a pair of aligned mounting bars (FIG. 6) which are connected by side plates 122 and a center plate 124 (FIG. 7) disposed intermediate the side plates 122. The mounting bars 120 are bolted against the underside of the track member 84 on the draw bar 80 (FIG. 6). Extended between the lower ends of the side and center plates 122 and 124 and the mounting bars 120 are brackets 126 having solenoids 128 mounted thereon with the armatures of the solenoids 128 operating in a direction parallel to the mounting bars 120 and the track member 84. Each solenoid 128 operates a drive pawl 130. One pawl 130 projects upwardly from the space between the center plate 124 and one of the side plates 122, and into a slot 132 (FIGS. 5 and 6) in the track member 84. When actuated by its solenoid 128, this pawl 130 lifts upwardly still further, engages a tooth in the overlying ratchet bar 108, and shifts that bar 108 a distance equal to the pitch of the ratchet teeth. The other drive pawl 130 projects upwardly from the space between the center plate 124 and the other side plate 122 and into another slot 132 in the track member 84. This slot 132 underlies the other ratchet bar 108 so that when the second pawl 130 is actuated it too lifts upwardly. engages the teeth of the ratchet bar 108 above it and moves that bar 108. Since the teeth of the two ratchet bars 108 are oriented in opposite directions, one pawl 130 will move the pick-up assembly 40 in one direction and the other will move it in the opposite direction.  
  Each pawl 130 possesses a triangular configuration (FIG. 6). and at its rear end is provided with a slot 134 which is disposed horizontally when the pawl 130 is in its drive position. that is its uppermost position (FIG. Extended through the slot 134 is a pin 136 which is anchored in a fixed position to the side and center plates 122 and 124. Near its front end and below the corner which actually engages the ratchet bar 108 the pawl 130 is provided with an oblique slot 138 through which another pin 140 extends. Unlike the pin 136, the pin 140 is not anchored in a fixed position in the side and center plates 122 and 124, but on the contrary, is confined in a horizontal slot 142 in the side and center plates 122 and 124 so that it can shift horizontally with the pawl 130.  
  The pawl 130 is disposed within a yoke 144 through which the pin 140 also extends so that the pawl 130 and its yoke 144 are connected together through the hori zontally shiftable pin 140. The yoke 144 in turn is con nected rigidly to a draw bar 146 which extends to and is connected with the armature of one of the solenoids 128. Extended between the rear end of the pawl 130 and the bracket 126 for the solenoid 128 which oper ates the opposite pawl 130 is a spring 152 which urges the pawl 130 to its retracted or lowermost position and draws the armature for its solenoid 128 outwardly.  
  When the solenoid 128 is energized, it of course draws its armature inwardly and the armature in turn moves the drive bar 146 horizontally. Since the pin 140 is connected to the drive but 146 through the yoke 144. the pin 140 will likewise shift in its horizontal slots 142. With respect to the pawl 130, during the initial incre ment of movement the pin 140 merely shifts from one end of the oblique slot 138 therein to the other end of that slot. This causes the front end of the pawl 130 to lift upwardly or raise to its drive position. but the rear end of the pawl 130 merely pivots about the pin 132 which remains near the forward end of the horizontal slot 134 due to the force applied by the spring 152. During the final increment of movement for the solenoid armature. pin 140 engages the lower end of the oblique slot 138 and moves the entire pawl 130 longitudinally against the force exerted by the spring (FIG. 6). As this occurs, the slot 134 at the rear end of the pawl 130 moves with respect to the pin 136 extended through it. Thus. when the solenoid 128 is initially retracted. the pawl 130 moves upwardly through its slot 132 in the track member 84 and is positioned between two teeth of the overlying ratchet bar 108. Thereafter. the pawl 130 shifts horizontally and engages a tooth of the ratchet bar 108, thus shifting the bar 108 and the entire pick-up assembly 40 within the draw bar 80. The movement of the pawl 130 is enough to drive the ratchet bar 108 a distance equal to the pitch of its teeth. When the solenoid 128 is deenergized, the spring 152 draws the pawl 130 rearwardly, while the weight of the pawl causes it to fall downwardly away from the ratchet bar 108. This in turn causes the pin to shift through the oblique slot 138 in the pawl 130 and along the horizontal slots 142 in the side and center plates 122 and 124. Therefore, when the solenoid 128 is again energized the ratchet bar 108 will again be engaged and advanced a distance equal to the pitch between adjacent ratchet teeth, and in so doing will advance the pick-up assembly 40 still further. Of course. energizing the other solenoids 128 will cause the other pawl 130 to rise and engage the opposite ratchet bar 108 to move the pick-up assembly 40 in the opposite direction.  
  Also housed in the two spaces between the center plate 124 and the two sideplates 122 are detents (FIGS. 6-8) which. like the pawls 130, project upwardly through the slots 132 in the track member 84. The detents 150, however, remain engaged with the teeth of the ratchet bars 108 to prevent the pick-up assembly 40 from shifting when not engaged by one of the pawls 130. The detents 150 pivot about the pins 136 and are urged upwardly by springs 148 extended between their lower ends and downward extensions of the center plate 124. The lower ends of the detents 150 bear against adjustable stops at the lower ends of the side plates 12. Of course, as the pickup assembly 40 is moved by the pawls 130 the two detents retract and engages different teeth of the ratchet bar 108.  
  The solenoids 128 are controlled by a computer which directs electrical pulses to them. The number of pulses determines the distance the pickup assembly will move, while the solenoid 128 to which those pulses are directed determines the direction of movement. For example, if it is desired to have the pick-up assembly engage three more gripping balls 62 on the downward movement ofthe draw bar 80, the innermost solenoid 128 is energized three times. by directing three pulses to it. This moves the pawl 130 connected to that solenoid three times, thereby advancing the overlying ratchet bar 108 and pick-up assembly 40 a distance equal to three teeth. Consequently. three more gripping balls 62 enter the interior of the pick-up assembly 40 and will be disposed below the gripping strip 106 thereof.  
  Each drive assembly 44 (FIG. 3) operates a plurality of draw bars 80, moving them from their lowermost position to their uppermost position where the pick-up assemblies 40 in them can engage or disengage gripping balls 62 on the operating wires 60, and thence downwardly again. As the draw bars 80 move downwardly the operating threads 50 connected with the gripping balls 62 engaged by the pick-up assemblies 40 are likewise drawn downwardly, and this moves the working threads 10 connected with those displaced operating threads 50 outwardly. The end result is the creation of a shed opening 0 in each of the groups g of working threads 10 associated with the draw bars 80 connected to the drive assembly 44.  
  Each drive assembly 44 includes a reversible rotary actuator which may be of the hydraulically operated variety. The actuator 160 is bolted to a vertical mounting plate 162 attached to the framework 2 below the frame assemblies 38, and has a crank arm 164 which moves through The crank arm 164 abuts against elastomeric stops 166 at the ends of its arcuate movement, and the stops 166 are also bolted to the mounting plate 162.  
  Fastened to the mounting plate 162 above actuator 160 are vertical rails 168 of circular cross section, and these rails 168 guide a crosshead 170, confining it to truly vertical motion. Actually. the crosshead 170 is provided with grooved rollers 172. the grooved peripheries of which engage the rails 168 so that the cross head 170 follows the rails 168 as it moves. The crank arm 164 is connected to the cross head 170 through a connecting arm 174. Thus. as the crank arm 164 swings from the lower stop 166 to the upper stop 166 it moves the crosshead 170 from its lower position to its upper position. Moreover, the crank arrangement causes the crossarm to experience a gentle acceleration and decel eration at the beginning and end of its upward move ment.  
  The cross head 170 is attached to the draw bars 80 of a plurality of adjacent frame assemblies 38 by tie rods 176 (FIG. 3). Therefore. as the crosshead 170 is elevated through operation of its rotary actuator 161). it in turn will elevate the draw bars 80 connected to it. The draw bars 80 remain in a perfectly horizontal disposition as they rise due to the effect thereon of the pulleys 90 and stabilizing cables 92. When the rotary actuator 160 is reversed the crosshead 170 and draw bars 80 connected thereto will. of course. descend to their initial positions.  
  The rotary actuator is operated by the same computer which operates the solenoids 128 of the indexing assemblies 42.  
  It should be apparent from the foregoing discussion that the frame assemblies 38 are spaced at equal intervals around the center axis of the weaving machine 14, there being one frame assembly 38 for each group g of working threads 50. The draw bar 80 of each frame as sembly 38 carries a pick-up assembly 40 and indexing assembly 42. Finally. the drive assemblies 44 are also spaced at equal intervals around the center axis of the weaving machine M. but they are fewer in number than the frame assemblies 38 since one drive assembly 44 elevates several draw bars 80.  
 OPERATlON To prepare the weaving machine M for operation the upper ends of the longitudinal threads b are embedded in glue above the mandrel m (FIG. 1). while the lower ends are spliced to the working threads 10 which extend through the apertured guide plates 12. Indeed. the guide plates 12 arrange the working threads 10 and likewise the longitudinal threads 11 in the radial groups g with equal spacing between the groups g and between the individual threads 1) within the groups g. Thereafter. the upwardly extending terminal ends of the operating threads 50 are lowered or raised to bring the gripping balls 62 on the operating wires 60 to the prescribed height, That height is below the gripping strips 106 on the pick-up assembly 40 when the pick-up assembly 40 is in its raised position. and is such that the open end that the pick-up assembly 40 will align with and receive the gripping balls 62 as it is moved inwardly (FIGS. 4 and 5). ln this regard. all ofthe working threads are initially in their iii-shed positions, that is none is displaced outwardly to form a shed opening 0, and all of the pick-up assemblies 40 are in the outermost positions. Once the gripping balls 62 are brought to the prescribed height. the terminal ends of the operating threads 50 are secured at the anchor pegs 58.  
  The bobbin 26 containing the wrap thread a installed on the carriage 24, and the wrap thread a is threaded through the filament insertion device 28 and secured to the mandrel mount 6 along with the longitudinal threads b.  
  After the longitudinal threads h and wrap thread a are properly installed, the weaving machine M is energized. In particular, the motor of the carriage 24 is energized along with the computer which operates the solenoids 128 of the various indexing assemblies 42 and the rotary actuators 160 of the several drive assemblies 44. The motor drives the carriage 24 around the slotted track 20. and as it does the wrap thread a plays out through the filament insertion device 28.  
  The position of the carriage 24 is part of the input to the computer, and that computer actuates the rotary actuators 160 of the drive assemblies 44 such that the crosshead 170 which is 180 from the carriage 24 is in its elevated position. while the crosshead 170 immediately ahead of the carriage 24 is in its lowermost position. Moreover, while the crosshead 170 which is 180 from the carriage 24 is in its elevated position. the coniputer will operate the solenoids 128 of the several in dexing assemblies 42 lifted by that crosshead 170 so that the pick-up assemblies will become engaged with or detached from gripping balls 62 on the depending operating wires when that crosshead 170 descends.  
  Now considering only one frame assembly 38 and the pickup assembly 40 and indexing assembly 42 associated with it, the draw bar of this frame assembly 38 will rise with the crosshead to which it is attached when the carriage 24 passes beyond it and approaches a position from it. Actually, the crosshead 170 is elevated by the rotary actuator 160 which is connected to it through the crank arm 164 and connecting arm 174. The gripping balls 62 suspended from the operating wires 60 and operating threads 50 for the group g associated with the frame assembly 38 under consideration align with the slot-like opening in the drawn bar 80. and as that draw bar 80 is elevated by the crosshead 170. the gripping balls 62 eventually enter the slot like opening (F168. 4 and 5). When the draw bar 80 is in its uppermost position the gripping balls 62 will be dis posed within the interior of the draw bar 80. All of the balls 62 which enter the slot will be at the same elevation and spaced at equal intervals.  
  Prior to the initial pass ofthe carriage 24, the pick-up assembly 40 will be in its outermost position, in which case it will not be engaged with any ofthe gripping balls 62, nor will it interfere with any ofthe gripping balls 62 as the draw bar 80in which it is housed rises. However. once the draw bar 80 reaches its uppermost position, the computer energizes the indexing mechanism 42 by directing electrical pulses to the solenoid 128 which drives the pick-up assembly 40 inwardly. The number of pulses directed to the solenoid 128 depends on the number of gripping balls 62 which are to be engaged which in turn is dependent of the location of the shed opening 0 in the weaving schedule for the particular group g of working threads 10 associated with the frame assembly 38. For example. if the weaving schedule calls for the shed opening 0 to be located between fourth and fifth longitudinal threads 11 from the outside of the group g. the solenoid 128 which drives the pickup assembly 40 inwardly will receive four pulses.  
  Each time the solenoid 128 receives a pulse, the pawl 130 connected to it moves upwardly into engagement with a tooth of the ratchet bar 108 and then shifts hori zontally a distance equal to the spacing between adjacent teeth on the bar 108. This spacing equals the distance between adjacent gripping balls 62 so that four pulses move the gripping assembly 40 inwardly a dis tance of four gripping balls 62.  
  With the initial incremental move the open end of the pick-up assembly 40 passes over the gripping ball 62 on the outermost wire 60 so that after four pulses of the soienoid 128 the four outermost gripping balls 62 in the group g are positioned beneath gripping strips 106 of the pickup assembly 40 with the operating wires 60 attached thereto being extended upwardly through the slots in the tops of the pick-up assembly 40 and the draw bar 80.  
  The computer positions all of the pick-up assemblies 40 on a single crosshead 170 simultaneously, and once they are positioned the rotary actuator 160 for that crosshead 160 is lowered. This lowers the draw bars 80 and along with them the pick-up assemblies 40. Again, considering only one frame assembly 38, the pick-up assembly 40 in the draw bar 80 of that frame assembly 38 engages the gripping balls 62 disposed within it along the gripping strips 106 and draws those balls 62 downwardly along with the operating wires 60 attached thereto. The operating wires 60 in turn pull the operating threads 50 from which they are suspended and the operating threads 50, being connected to the working threads 10 at their upper ends. pull those working threads outwardly. Thus, where four gripping balls 62 are engaged by the pick-up assembly 40, the four outermost operating threads 50 will be drawn downwardly and the four outermost working threads will be drawn outwardly to the outshed position so that the shed opening 0 will be located between the fourth and fifth threads from the outside.  
  Those working threads 10 which are displaced outwardly to the outshed position are moved far enough to be disposed entirely with the slots 22 of the track 20. The displaced threads 10 remain in this position until the draw bar 80 associated with them is again elevated. in the meantime. the carriage 24 passes over the frame assembly 38. that is through the same angular position as the carriage 38, and the filament insertion device 28 lays the wrap thread u into the shed opening 0 close to the apex thereof.  
  The foregoing steps are repeated for each frame assent bly 38 so that once the carriage 24 has completed one revolution the wrap thread a will have been laid in the shed openings 0 of each group g of longitudinal threads [1 or if the weaving schedule calls for no shed openings 0 in a particular group g, then past that group When the carriage 24 again reaches a position 180 opposite the frame assembly 38 under consideration. the crosshead 170 for that frame assembly 38 will have again elevated its draw bar 80 to its uppermost posi tion. At this time the computer may not energize either solenoid 128 ofthe indexing assembly 42, in which case the pickup assembly 40 will draw the same number of operating threads 50 on its next descent and the shed opening 0 will remain in the same place; the computer may energize the solenoid 128 which drives the pick-up assembly 40 inwardly, in which case the pick-up assembly 40 will draw more operating threads 50 downwardly and the shed opening 0 will be located further to the center; or the computer may energize the solenoid 128 which moves the pick-up assembly outwardly, in which case the less operating threads will be drawn outwardly and the shed opening 0 will move outwardly. The particular solenoid 128 energized and the number of pulses received depends on the weave programmed into the computer.  
  The operations heretofore described for the shed mechanism S are repetitive, and as the carriage 24 continues to revolve about the track 20 the tubular weave w builds up about the mandrel m. In order to maintain the apexes of the shed openings 0 at approximately the same elevation of mandrel m is raised as the weave w grows.  
  This invention is intended to cover all changes and modifications of the example of the invention herein chosen for purposes of the disclosure which do not constitute departures from the spirit and scope of the invention.  
 What is claimed is:  
  1. In a weaving machine having longitudinal threads arranged in groups with the threads of each group being side-by-side, a device for creating shed openings in the groups so that another thread can be passed through the shed openings to effect a weave; said device comprising: a connector engaged with each longitudinal thread for displacing its longitudinal thread when the connector is moved, the connectors for the longitudinal threads of each group being arranged in a line; pick-up means for engaging a selected number of the connectors of a line of connectors; selector means connected to the pick-up means for moving the pickup means in the direction ofthe line of connectors and for thereby varying the number of connectors engaged by the pickup means; and drive means for moving the pick-up means such that the connectors engaged by the pick-up means move, whereby the longitudinal threads are displaced and a shed opening may be created in the individual groups of longitudinal threads.  
  2. A device according to claim 1 wherein the connec tors are enlarged at their ends; wherein the pick-up means has an open end and a hollow interior leading from the open end; and wherein the selector means moves the pick-up means such that the open end thereof receives the enlarged portions on the connectors in a line as the pick-up means moves toward and along the line of connectors.  
  3. A device according to claim 2 wherein each connector includes an elongated flexible element.  
  4. A device according to claim 3 wherein the elongated flexible element for each connector depends downwardly and the enlarged portion of the connector is suspended from the depending flexible element.  
  5. A device according to claim 4 wherein the pick-up means and selector means are carried by a draw bar, and the drive means moves the draw bar upwardly and downwardly, whereby when the draw bar moves downwardly the enlarged portions are engaged by the pickup assembly and the flexible elements are drawn downwardly.  
  6. A device according to claim 2 wherein the pick-up means and the selector means are mounted on a member which is shifted by the drive means; wherein the pick-up means has ratchet teeth thereon; and wherein the selector means includes a pawl for engaging the ratchet teeth and shifting the pick-up means. and actuating means for moving the pawl.  
  7. A device according to claim 6 wherein the pick-up means has two sets of ratchet teeth with the teeth of one set being oriented in the direction opposite to the teeth in the other set, and wherein the selector means includes two pawls with one pawl being engageable with one set of ratchet teeth for moving the pick-up means in one direction, and the other pawl being engaged with the other set of ratchet teeth for moving the pick-up means in the opposite direction.  
  8. In a circular weaving machine having longitudinal threads arranged in radial groups about the center axis of the weaving machine, a device for creating shed openings in the radial groups so that a wrap thread can be passed through the shed openings to effect a weave; said device comprising elongated connectors including thread-like elements connected with the longitudinal threads of each group and extended outwardly therefrom and thereafter depending downwardly and further including enlarged elements suspended from the depending portion of the thread-like elements. the connectors also being arranged in groups such that a group of connectors is associated with each group of the longitudinal threads, pick-up means for each group of connectorseach pick-up means being engageable with the enlarged elements of the connectors of a group. selector means for each pick-up means for varying the number of connectors engaged by that pick-up means, and drive means for moving the pick-up means so that the engaged connectors will be displaced whereby the longitudinal threads connected with the displaced connectors will also be displaced.  
  9. In a circular weaving machine including means for arranging longitudinal threads in radial groups about the center axis of the machine with the longitudinal threads of each radial group being positioned within a radially extending plane passing through the center axis and with succeeding longitudinal threads of each group being located further from the center axis, and further including threading means moving circumferentially around the center axis and through the groups oflongitudinal threads for laying a wrap thread in the radial groups so as to form a generally circular weave; a device for creating shed openings in the radial groups so that the threading means can deposit the wrap thread in the shed openings said device comprising: elongated connectors having inner ends connected with the longi tudinal threads and extending outwardly away from the center axis, the connectors also being arranged in groups such that each group of connectors is associated with a different group of longitudinal threads, the opposite ends of the connectors for each group being arranged in a row which lies generally in a radial plane. pick-up means for each group of connectors for engaging a selected number of the connectors at their opposite ends. selector means connected to the pick-up means for varying the number of connectors engaged by the pick-up means, and drive means for moving the pick-up means such that the connectors engaged by the drive means move, whereby the longitudinal threads associated with the engaged connectors are displaced and shed openings may be created in the individual groups of longitudinal threads and the position of a shed opening in a group may be changed 10. The structure according to claim 9 wherein the connectors of each group including the opposite ends of those connectors lie generally in the same radial plane as the longitudinal threads associated with and controlled by the connectors of that group.  
  11. The structure according to claim 10 wherein the pick-up means for each group is moved radially by the selector means generally in the plane of that group and along the opposite ends of the connectors.  
  12. The structure according to claim 11 wherein the center axis is upright and the connectors after extend ing outwardly depend downwardly with said opposite ends being at the lowest portions of the connectors; wherein the pick-up means for each group moves radially to vary the number of connectors engaged thereby, and the drive means when actuated moves the pick-up means downwardly to pull the engaged connectors downwardly and thereby draw the inner ends otthe engaged connectors and the longitudinal threads connected therewith outwardly away from the center axis.  
  13. The structure according to claim 12 wherein the center axis is upright and the downwardly opening included angles between the center axis and the longitudinal threads are always acute angles.  
  14. The structure according to claim 13 wherein the weave is formed about a mandrel of circular crosssection and having large and small diameter ends with the small diameter end being below the large diameter end.