Abstract:
A connecting device for connecting a motion transmission element to a heddle frame in a weaving loom wherein the connection device includes a tenon member and mortise member which are cooperatively engaged with respect to one another. The tenon member includes a nut mounted to the transmission element, an anchoring block through which the transmission element extends and which cooperates with surfaces of the mortise member, a bush through which the transition element passes and which bush cooperates in rotation with the nut and which also includes a counter-nut for securing the bush against the anchoring block.

Description:
BACKGROUND OF THE INVENTION 
     The present invention relates to a device for coupling a heddle frame on a movement-transmission element of a weave system. The invention also relates to an assembly for driving the heddle frames, to a weaving loom incorporating such a device, and to a weaving loom equipped with such a device or such an assembly. 
     DESCRIPTION OF THE RELATED ART 
     It is known to provide mechanical systems for connecting the frames of a weaving loom with rods or cables driven with a vertical oscillating movement by a weave system, particularly a dobby. EP-A-0 297 003 and EP-A-0 467 808 provide using elements forming tenon and mortise respectively, this allowing an efficient and rapid anchoring of the frame on the transmission element. However, such known devices present certain limitations. 
     The device of EP-A-0 297 003 provides a longitudinal adjustment of the tenon on a movement-transmission rod by adherence and wedging, thanks to wedde-shaped elements. In the event of poor clamping of these elements, a considerable risk of slide exists, which may lead to serious damage to the weaving loom, particularly by blockage of the frames and/or breakage of the connecting rods. 
     The device of EP-A-0 467 808 provides that the adjustment in height is of the micrometric type thanks to a tenon comprising a tapped central orifice, which avoids risks of untimely slide. However, this device is such that the surfaces of the tenon and mortise in contact are relatively small, while intense efforts are transmitted thanks to these surfaces, with considerable accelerations, hence a risk of premature wear of these surfaces by caulking. 
     It is a particular object of the present invention to overcome these drawbacks by proposing a novel coupling device in which a member forming tenon is secured with respect to a movement-transmission element, while the surfaces in contact of this tenon-forming element and of the mortise-forming element associated therewith are sufficiently large to withstand intense efforts. 
     SUMMARY OF THE INVENTION 
     To that end, the invention relates to a device for coupling a heddle frame on a movement-transmission element of a weave system, this device comprising a male member forming tenon mounted on the transmission element and a female member forming mortise fixed on an upright of the frame, the mortise member being provided with a central slot for passage of the transmission element and defining, on either side of this slot, contact surfaces intended to cooperate with the tenon member for transmission of the efforts, characterized in that the tenon member is formed by an assembly comprising: 
     a nut screwed on the transmission element; 
     an anchoring block forming at least two surfaces intended to cooperate with the contact surfaces of the mortise member, this block being provided with a through bore for passage of the transmission element and for reception, with possibility of rotation, of the nut, 
     a bush provided with a central bore for passage of the transmission element and adapted to drive the nut in rotation about the transmission element, through the bore of the block, and 
     a counter-nut for clamping the bush against the afore-mentioned block and nut. 
     Thanks to the invention, the dimensions of the block may be provided so that its surfaces intended to cooperate with the mortise member are relatively large, while the adjustment of the longitudinal position of the tenon member does not oblige the block to undergo a movement of rotation about the threaded rod constituting the transmission element, which would not be compatible with the usual density of implantation of the frames in a weaving loom. In other words, the nut and the bush make it possible to obtain adjustment of the position of the block along the transmisison element without inducing rotation of this block, the block thus being able to conserve a suitable orientation with respect to the mortise element borne by the frame. 
     According to advantageous aspects of the invention, the device incorporates one or more of the following characteristics: 
     The nut and the bush are provided with elements in relief of corresponding shapes allowing a claw coupling of the nut and the bush. 
     The bush is provided with a polygonal-section head, enabling it to be driven in rotation by means of a conventional spanner. 
     The bore of the block comprises two inner shoulders turned respectively towards the two openings of this bore and intended to cooperate respectively with corresponding surfaces of the nut and of the bush. These two inner shoulders make it possible to control the position of the block along the transmission element thanks to the nut and the bush. 
     The block is provided with at least one protuberance adapted to be engaged in the slot of the mortise member. This protuberance ensures a suitable positioning of the block with respect to the mortise member and to the environment of the frame. 
     The block is provided with an extension directed opposite the mortise member when the tenon member is in place in the mortise member, this extension being adapted to be engaged in a slideway for guiding and retaining the tenon member. In that case, this extension advantageously presents a transverse section substantially in the form of a T. 
     The invention also relates to an assembly for driving the heddle frames of a weaving loom, which comprises at least one device as described hereinbefore and a set of guides adapted each to receive an extension of the block of such a device, each guide presenting, in transverse section, a shape such that it opposes an extraction of the extension in a direction substantially perpendicular to the direction of slide of the extension in the guide in question. In addition, the guide may be provided to be mobile in a direction substantially perpendicular to the direction of slide, which makes it possible to control a movement of introduction/extraction of the tenon member with respect to the mortise member. 
     Finally, the invention relates to a weaving loom equipped with a device or an assembly as described hereinbefore. Such a loom is easier to use, particularly when frames are changed, which is a regular process during use of such a loom. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention will be more readily understood on reading the following description of an embodiment of a device and assembly in accordance with its principle employed in a loom likewise according to the invention, description given solely by way of example and made with reference to the accompanying drawings, in which: 
     FIG. 1 is an exploded view in perspective of a device according to the invention. 
     FIG. 2 is a longitudinal section of the device of FIG. 1 in mounted configuration. 
     FIG. 3 is an exploded view in perspective, on a larger scale and with parts cut away, of the element forming tenon. 
     FIG. 4 is a section along line IV—IV in FIG. 2, and 
     FIG. 5 schematically shows part of a weaving loom according to the invention. 
    
    
     DESCRIPTION OF PREFERRED EMBODIMENT 
     Referring now to the drawings, a heddle frame  1  of a loom M is intended to be driven by a dobby  2  thanks to movement-transmission elements which include a rod  3  for connection between the dobby and a bent lever  4 , this lever and this rod being connected by a synchronism bar  5  to a second bent lever (not shown) disposed on the other side of the loom M. The bent lever  4  is connected by a rod  6  to a slide block  7  guided by rails  8  and  8 ′. The slide block is itself connected to an elongated effort-transmission element which is formed by a rod  9  threaded over at least a part of its height. 
     Reference  11  denotes the upper upright of the frame  1  and  12  its lateral upright on the rod  9  side. The upright  12  has a longitudinal groove  13  with rounded bottom cut out therein for receiving the rod  9 . The upright  12  is likewise provided with three through orifices  14  allowing the mounting of an attachment  20  forming mortise, and which is constituted by two vertical plates  21  and  22 , between which a spacer member  23  is arranged. The plates  21  and  22  are provided with three orifices  24  provided to be aligned with the orifices  14  when the attachment  20  is mounted on the frame  1 . Screws  25  or rivets allow the attachment  20  to be immobilized on the frame  1  by traversing the orifices  14  and  24 . 
     Each plate  21  and  22  has a notch  261 ,  262  respectively cut out therein, oriented on the groove  13  side when the attachment  20  is mounted on the frame  1 . X-X′ denotes the principal direction of the lateral upright  12  of the frame  1 . The notches  26 , and  262  are respectively defined by lower edges  27  and upper edges  28 , these edges  27  and  28  being substantially perpendicular to the direction X-X′, i.e. substantially horizontal, when the loom is in configuration of use. 
     A space is defined between the plates  21  and  22 . This elongated space constitutes a slot  29  for partially receiving the rod  9 , as will be described below. 
     An assembly  40  forming a tenon is provided to be mounted on the rod  9  and introduced partially in the notches  26   1  and  26   2  in order to interact with the edges  27  and  28 . 
     This assembly  40  comprises a nut  41  intended to be screwed on a threaded part  9   a  of the rod  9 . This nut  41  has a substantially cylindrical outer radial surface  42  and presents two teeth  43  and  44  each extending in a direction substantially parallel to a central axis X 1  of the rod  9  when the nut  41  is in place on this rod. 
     The assembly  40  also comprises a block  45  provided with a through bore  46  which is not tapped and whose dimensions are such that the block  45  may freely slide around the threaded part  9   a.    
     As is more clearly visible in FIG. 3, the inner radial surface of the bore  46  is provided with a flange  47  defining two shoulders  48 ,  49  respectively oriented towards the lower opening  46   a  and towards the upper opening  46   b  of the bore  46 . When the block  45  rests on the nut  41 , the shoulder  48  is in abutment on the upper surface  41   a  of the nut  41 . 
     The block  45  is provided with a protuberance  50  whose width L 50  is slightly less than the width  129  of the slot  29 , with the result that this protuberance  50  may be engaged in the slot  29  of the attachment  20 . The protuberance  50  is interrupted by the bore  46 . 
     On either side of the protuberance  50  there are defined two surfaces  51  and  52  intended to come into abutment against the upper edges  28  of the notches  26   1  and  26   2 . The length L of the surfaces  51  and  52  is relatively great, which allows a distributed abutment of the block  45  on the edges  28 . 
     The lower surface  53  of the block  45 , i.e. the surface opposite surfaces  51  and  52 , forms a bearing surface engaged by the edges  27  of the notches  26   1  and  26   2 . 
     According to an embodiment of the invention which has not been shown, it would be possible to provide a protuberance similar to protuberance  50  on surface  53 . 
     The block  45  is also provided with an extension  54  of substantially T-shaped cross-section, which is intended to be engaged in a guide in the form of a slideway  100  defining a groove  101  with an inner section substantially in the form of a T. The minimum width  1   101  of the groove  101  is less than the maximum width  1   54  of the extension  54 , with the result that, once engaged in the groove  101 , the extension  54  cannot be displaced in the plane of the frame in a direction Y-Y′ perpendicular to its direction X 2  of slide in the guide  100 . 
     A bush  55  also belongs to the assembly  40  and is provided with a central bore  56  of sufficient diameter to allow the bush  55  to slide around the part  9   a  of the rod  9 . The bush  55  is provided with an outer radial flange  57  intended to come into abutment against the shoulder  49  when the lower part  58  of the flange  57  is engaged in the bore  46 . Part  58  is provided with teeth  59  and  60  adapted to mesh with teeth  43  and  44  of the nut  41 , through the bore  46 , which allows elements  41  and  55  to be connected in rotation. 
     The bush  55  is also provided with a hexagonal or other polygonal shaped head  61  allowing it to be rotated with the aid of a conventional spanner 
     A counter-nut  62  is also provided in the assembly  40  which is screwed on part  9   a  of the rod  9  in order to block the bush  55  against the block  45  and the nut  41 . The tenon member  40  therefore comprises an assembly formed by elements  41 ,  45 ,  55  and  62 . 
     Thanks to the dimensions of the surfaces  51 ,  52  and  53 , the tenon member  40  bears against the mortise member  20  over relatively large areas, which avoids a caulking of surfaces  51  to  53  or of edges  27  and  28 . 
     Adjustment of the position of the assembly  40  along the rod  9  is micrometric and effected thanks to the nut  41  on which th bush  45  rests. In effect, when the position of the assembly  40  is to be adjusted, it suffices to rotate the bush  55  by hand to drive the nut  41  in rotation, which then rotates freely inside the bore  46  and moves along the rod  9 , driving the block  45  in translation without driving it in rotation. When the desired position is attained, it suffices to tighten the counter-nut  62  against the bush  55  by using the hexagonal head  61 , which has the effect of firmly immobilizing the assembly  40 , and in particular the block  45 , on the rod  9 . The longitudinal position of the assembly  40  is adjusted with respect to the rod  9  without the block  45  being rotated, which makes it possible to maintain the extension  54  in place in the guide  100  and avoids an interference between adjacent tenon members in a weaving loom. 
     Elements  50  and  54  both have the function of guaranteeing correct positioning of the block  45  with respect to the slot  29  and, in a variant, one only of these elements may be employed on a block of a device according to the invention. 
     The invention presents the particular advantage that, in the event of a restricted number of heddle frames being used for weaving a piece of material, the rods  9  which are not associated with frames are maintained in substantially vertical positions by the cooperation of the extensions  54  and of the guides  100 , with the result that they cannot fall or get hooked. 
     As is more clearly visible in FIG. 5, each guide  100  may be mounted on a support  102  articulated about an axis  103  with respect to an element  104  of the framework of the loom M, which makes it possible to envisage a movement F transverse with respect to the direction X-X′, i.e. a movement of approach or of moving away of the guides  100  and of the tenon members  40  of the loom with respect to the mortise members  20  in direction Y-Y′. 
     One sole support  102  may, of course, be used for all the guides  100  of a weaving loom. 
     As is also visible in FIG. 5, the guide rails  8  and  8 ′ may be supported by the support  102 , which enables each rod  9  to be pivoted over the whole of its length. 
     Other modes of adjusting the position of the tenon members in the direction Y-Y′ may be considered, such as adjusting members incorporating a screw, eccentric or slideway. 
     In any case, an assembly for driving the frames in the weaving loom according to the invention allows an easy and simultaneous positioning of the tenon members associated with the movement-transmission elements in the mortise members associated with different frames, possibly with the assistance of a motor. 
     The invention has been shown with a positive dobby. It is, of course, applicable with a negative dobby, such as the one disclosed, for example, in EP-A-0 297 003 and, more generally, in any weaving loom in which the heddle frames must be set in motion, for example with a cam mechanism.