Loom weft feeder with spaced-out spools and diameter-adjustable drum

Abstract

The present invention provides a weft yarn supply device with a separate yarn winding mechanism, equipped with a drum having a diameter that can be fully adjusted with a single operation. [Solution] The weft supply device has a drum (D) composed of a plurality of fixed members (5), each of which has a support shank housed in a seat formed in a static support disc coaxial with the drive shaft (A) of the weft supply device, the spacing between the spaced-out winding bodies on the drum is caused by the vibration and tilting motion of a plurality of moving members, each of which has a support shank housed in a seat formed in a tilting support disc that is eccentric with respect to the drive shaft of the weft supply device and deforms, and an elastic member is provided that applies compressive force to the support shank to maintain the fixed member and the moving member in a stable engaged position within their respective seats.

Description

Technical Field

[0001] The present invention relates to a novel weft supply device for a loom having spaced yarn winding bodies, particularly for an air jet loom and a water jet loom. In particular, the weft supply device for the loom enables particularly rapid adjustment of the drum diameter in addition to the normal functions provided by current weft supply devices of known types.

Background Art

[0002] As is well known, a weft supply device is a device that intervenes between a loom and a yarn bobbin and supplies weft to the loom. The weft is accumulated on a cylindrical drum as continuously spaced yarn winding bodies at a constant speed as much as possible (clockwise or counterclockwise according to the characteristics of the yarn), thereby forming a reserve of weft. Then, while the weft is being drawn out axially from the weft supply device drum at a variable speed - while the weft is being inserted into the shed - it prevents a peak in tension from occurring in the weft and ensures that neither the integrity of the yarn itself nor the quality of the fabric is impaired.

[0003] Weft supply devices have been widely used in weaving factories for many years. Over time, in addition to the above basic functions, functions such as monitoring the constant presence of weft at important points of the weft supply device, adjusting the amount of weft accumulated in reserve and the mutual distance, i.e., pitch, between each yarn winding body, braking the weft to suppress the dynamic effects caused by sudden changes in the drawing acceleration, measuring the length of the weft section drawn out by the insertion device, and stopping the drawing of the weft when the supply of a predetermined length is completed have been added as additional control functions.

[0004] The amount of weft yarn stored in reserve naturally depends on the diameter of the weft supply drum on which the reserve is wound and the number of spools that can be accommodated on the drum at the same time. To expand the adjustment range of a single weft supply, making it applicable to both air-jet and water-jet looms with significantly different heights, the number of spools can be varied by changing the pitch between consecutive spools, and the drum diameter can also be changed. In fact, if the length of the inserted weft yarn corresponds to an integer multiple of the spools, and since there is only one stopping point for the weft yarn exiting the weft supply drum, the length can be finely adjusted by changing the drum diameter. For this purpose, the drum is usually composed of multiple (usually four) fixing members, each independently fixed to the weft supply body. In the case of a drum with an adjustable diameter, the fixing members are fixed to the weft supply body at an adjustable radial position and then clamped to the desired position by locking screws.

[0005] To automate and expedite this adjustment process, Patent Document 1 discloses a weft supply device equipped with a servo-controlled, irreversible gear system. This system allows simultaneous adjustment of the radial positions of three adjustable members of the weft supply device, and furthermore, the irreversibility of the gear system allows it to be locked in the desired adjustment position without the use of a locking screw. Each adjustable member is equipped with two parallel or slightly converging support shanks, and the gear system is connected to only one of these shanks, which is therefore provided with a rack. The other shank slides within its respective guide to improve the stability of the adjustable member. The fourth member is in a fixed position, and the presence of the weft is optically detected at this fixed position. Therefore, from the viewpoint of simplifying the structure, it was decided that this member would always be held at a constant distance and parallel to the weft supply device arm on which an optical sensor for detecting the weft is installed.

[0006] A weft supply device equipped with a device that separates each spool of yarn wound on a drum at a predetermined pitch, i.e., a type of weft supply device generally called a "weft supply device with spaced-out spools," further includes a corresponding number of movable members mounted on a stationary inclined flange. This flange is supported by the outer surface of a bush that is keyed to the eccentric part of the weft supply device shaft via a ball bearing, and the bush has an outer cylindrical surface that is inclined several degrees with respect to the drum surface. With this configuration, while the weft supply device shaft is rotating, the inclined bush rotates integrally with the shaft and the bearing's inner ring, causing a periodic compound oscillation in the bearing itself and the inclined flange fixed to the bearing's outer ring, which is integrated with it. This oscillation of the inclined flange is transmitted to the movable members, specifically to gripping finger-like members that periodically protrude from the drum fixing member for transmission. Here, the compound motion is composed of a combination of radial oscillation due to the eccentric part of the weft supply device shaft and inclination due to the rotation of the inclined bush. The complex movement of the gripping finger-like members of this moving component allows the spool of yarn wound on the drum to sequentially move in the direction of the area where the weft yarn exits the drum at a constant pitch that can be arbitrarily adjusted according to the inclination of the outer surface of the bush.

[0007] In the weft supply device with a spool for air-jet and water-jet looms, which is the subject of this invention, changing the drum diameter involves not only unlocking and locking the drum fixing members, but also unlocking and locking the movable members mounted on eccentric and inclined bushings. In fact, these movable members need to be repositioned according to the new radial position taken by the fixing members that make up the drum. Therefore, this is a fairly time-consuming operation, requiring a specialist to directly intervene in the weft supply device, loosen the locking screws of the four fixing members and four movable members, move all members to the new desired radial position, and finally tighten the locking screws again.

[0008] The solution described in Patent Document 1 above is not satisfactory for this purpose. This is because the adopted mechanical structure is quite bulky and is affected by the uncertainty of position due to play in the gear system, and because there is no locking screw for the fixed stop—it is only partially limited by the presence of preload springs or friction elements provided in each seat of the support shank of the adjustable member—it is activated by vibrations of the weft supply device during loom operation. Furthermore, when the positions of the three adjustable members are changed, the drum shape is determined as a whole by the fixed member and the three adjustable members, but since it is essential that at least one drum member is in a fixed position, an undesirable result occurs in that the drum shape is no longer a perfect circle. As a result, the operation of the gripping finger-like member of the moving member becomes significantly irregular and inefficient.

[0009] Patent Document 2 discloses a weft supply device with a spool that allows the radial positions of four fixed members to be changed by their respective radial displacement mechanisms. In this displacement mechanism, at least one main drive gear is coupled to individual sub-gears, which cause radial movement of each member of the drum via lead screw couplings. A similar mechanism is also provided for adjusting the radial position of the four movable members. Each member is supported by a single threaded shank with a circular cross-section, which cannot determine the precise and stable angular position of the member itself. Furthermore, since the radial displacement mechanism is not provided with a locking screw, the weft supply device is held in a stable working position by relying solely on the irreversible screw couplings of the fixed and movable members. Therefore, as described above, the solution disclosed in Patent Document 2 is not entirely satisfactory because the working position is somewhat uncertain due to the single threaded support shank, gear play, and system vibrations.

[0010] Patent Document 3 discloses a weft supply device with a spaced-out yarn winding body that reproduces the configuration disclosed in Patent Document 1, namely three adjustable members and one fixed member, and improves the adjustment method by introducing a central shaft with a rectangular cross-section into the adjustable members. The radial position of each member is actually changed by the cooperation of a disc having spiral ribs on one surface and complementary ribs formed on the opposing surface of the central shaft. Therefore, the adjustable member is equipped with a total of three shafts for adjusting the radial position: two lateral guide shafts with a circular cross-section and a central shaft with a rectangular cross-section. A similar structure is provided for adjusting the radial position of a movable member that spacees apart multiple yarn winding bodies wound on the weft supply device. The disc with spiral ribs is opposed to and integrated with a similar disc of the fixed member, and as a result both discs can be rotated by the same actuator, so that the radial positions of the fixed member and the movable member can be adjusted simultaneously.

[0011] Similarly, Patent Document 3 discloses a play adjustment system that acts on one of the lateral shanks of an adjustable member, which includes an elastic preload member that applies adjustable pressure to the shank by a dedicated actuator, the elastic pressure allowing longitudinal sliding of the shank while eliminating play in the released position, and locking the shank in the desired adjustment position in the locked position.

[0012] Patent Document 4 by the same applicant proposes an innovative solution in which the locking and unlocking of the fixed and movable members of the weft supply device are performed simultaneously with a single first servo control, and the positional fine adjustment of the fixed and movable members, i.e., the drum diameter, is performed simultaneously with a second servo control, even while the loom is in operation.

[0013] Both of the above solutions have proven effective in that they allow for the rapid and simultaneous adjustment of the fixed and movable members of the weft supply device with a separated yarn winding mechanism; however, Patent Document 3 is limited to three members. However, these are all particularly complex and sophisticated, making them expensive, and their commercial application is only expected in the production of high-quality textiles.

[0014] Therefore, the widespread demand in the textile industry for weft feeders with separate winding bodies for air-jet and water-jet looms—that is, the ability to quickly and effectively adjust all fixed and movable members simultaneously, i.e., the entire diameter of the drum, without significantly increasing manufacturing costs compared to existing similar weft feeders, i.e., at the same cost as conventional models where the fixed and movable members must be adjusted individually—remains unmet. [Prior art documents] [Patent Documents]

[0015] [Patent Document 1] International Publication No. 2015 / 169612 [Patent Document 2] U.S. Patent No. 5,671,783 [Patent Document 3] European Patent No. 3631065 [Patent Document 4] European Patent No. 3567144 [Overview of the Initiative] [Problems that the invention aims to solve]

[0016] Therefore, the technical problem that the present invention aims to solve is to provide a weft supply device with a spooling mechanism equipped with a drum having a diameter that can be fully adjusted in a single operation, thereby significantly reducing the time required for drum diameter adjustment work through a simple mechanical solution, without significantly increasing manufacturing costs.

[0017] In the context of this technical challenge, given that the current weft supply device drum diameter adjustment system already allows for simultaneous adjustment of the positions of fixed and movable members, the first objective of the present invention is to simplify the support structure of the fixed and movable members while maintaining high positional stability in the adjusted positions.

[0018] The second object of the present invention is to significantly shorten the unlocking / locking operation time of the fixed member and the moving member of the weft supply device.

[0019] Finally, the third object of the present invention is to control the play of the position adjusting device of the fixed member and the moving member, so that when the fixed member and the moving member are unlocked before the drum diameter is adjusted, the play is randomly distributed. By preventing this, accurate and reproducible drum diameter adjustment can be achieved in the first adjustment operation without the need to repeatedly adjust until the play is fully restored.

Means for Solving the Problems

[0020] This problem is solved by a weft supply device for a loom having a spaced yarn winding body and rapid adjustment of drum diameter, having the features defined in independent claim 1, and these objects are achieved. Other suitable features of this type of weft supply device with rapid adjustment of drum diameter are defined in the dependent claims.

Brief Description of the Drawings

[0021] Further features and advantages of the weft supply device for a loom having a spaced yarn winding body and rapid adjustment of drum diameter according to the present invention are given as non-limiting examples from the following detailed description of the preferred embodiments of the present invention, and will become more apparent as shown in the accompanying drawings. [Figure 1] It is an axial sectional view of a weft supply device for a loom that rapidly adjusts the drum diameter, incorporating the device of the present invention. [Figure 2] It is an exploded view of the winding area of the weft supply device of FIG. 1 including the stationary body, the inclined body, and the adjustment group connecting them in the first embodiment of the present invention. [Figure 3] It is an exploded view only of the stationary body of FIG. 2 including four fixed members forming the weft supply device drum. [Figure 4] It is an exploded view only of the inclined body of FIG. 2 including four moving members that cause separation between the yarn winding bodies wound on the weft supply device drum. [Figure 5] It is an exploded view of the adjustment group in FIG. 2 that can simultaneously adjust the radial positions of the fixed member and the moving member of the weft supply device. [Figure 6] It is a perspective view of the assembled weft supply device winding section in the second embodiment of the present invention. [Figure 7] It is an exploded perspective view of the same weft supply device winding area as in FIG. 6. [Figure 7A] It is an enlarged partial view of the inclined locking ring in FIG. 7. [Figure 8] It is a view similar to FIG. 7, showing the same weft supply device winding area as in FIG. 7 from the opposite side. [Figure 8A] It is an enlarged partial view of the closing ring in FIG. 8.

Embodiments for Carrying Out the Invention

[0022] According to the present invention, in order to solve the above-mentioned problems by a solution that is structurally much simpler than the configuration of the above-mentioned prior art but equally effective, all of the fixed member and the moving member are provided with a single central support shank that is generally trapezoidal right-angled columnar - preferably having an isosceles trapezoidal cross-section. With this shape, when the support shank engages with a seat portion that has a cavity of the same shape corresponding to the support shank and is also partially open, that is, substantially limited to the converging side walls of the support shank, the support shank causes self-centering and locking when it is pushed into the corresponding seat portion by a sufficient compressive force exerted on the trapezoidal right-angled column-shaped main bottom of the support shank. With this special configuration, the single shank of each fixed member and moving member can perform both the function of eliminating mechanical play and the function of adjusting the radial position of the member, which were conventionally entrusted to different support shanks for each member.

[0023] In the first embodiment of the present invention, the drum diameter of the weft supply device is adjusted without requiring the locking of the fixed member and the movable member. In practice, it is sufficient to act directly on the adjustment group to change the drum diameter of the weft supply device. To achieve this, the individual support shanks of the movable member and the fixed member are no longer fixed by their respective fixing screws, but are stably held in the desired operating position within their respective trapezoidal seats by a compressive force applied by an appropriate elastic member. In fact, because the member support shank is trapezoidal, the force applied to the main base of the trapezoidal shape by the elastic member generates a frictional force between the converging side wall of the support shank and the corresponding seat wall. This frictional force is sufficient to hold the member in the set adjustment position, even in the presence of stress generated by the yarn wound on the weft supply device drum or vibrations due to the variable acceleration of the weft supply device motor. However, this frictional force is still small enough that the support shank of the member can be translated radially with respect to the weft supply device axis, i.e., in the longitudinal direction of the shank. Therefore, after the driving action provided by the adjustment group, it becomes possible to directly adjust the drum diameter without having to perform the locking operation of the fixed member and the movable member beforehand.

[0024] This solution, since it no longer involves unlocking the components, conversely prevents the free redistribution of play that occurred in conventional weft supply devices with locking screws. This is because the play is strictly locked at a specific fitting position at all times by the presence of the elastic component. Therefore, this state not only allows for faster and more precise adjustment of the weft supply device drum diameter, but also reduces the number of fine adjustments required to stably obtain the desired drum diameter, and ensures excellent positioning of the fixed and movable components in subsequent weaving processes.

[0025] In a second embodiment of the present invention—specific application areas have been found in all weaving processes where the stress applied by the acceleration of the yarn or the weft supply device motor is very large, and the elastic member described in the first embodiment alone cannot completely counteract it—the action of the elastic member is complemented by a rapid tension fastener that is bistable between the locked and unlocked positions and has a very short operating time for the lock / unlock operation, thereby reducing the total time required for preparing and resetting the weft supply device before and after drum diameter adjustment to a negligible value of several tens of seconds. Thus, these problematic weaving processes can be carried out while maintaining the convenience of direct adjustment of the weft supply device drum diameter without compromising the convenience of the rapid tension fastener remaining inactive in all other weaving processes. [Typical configuration of a weft supply device with spaced-out winding bodies]

[0026] As is well known to those skilled in the art, the weft supply device, which has spaced-apart winding bodies schematically shown in cross-section in Figure 1, has as its main components an electric motor M housed in a base C, and the electric motor M rotates a hollow shaft A. The shaft A rotates a cup-shaped winding device G in its middle section and supports a stationary winding group W at its end by bearings. The winding device G rotates in a cavity between two cup-shaped members equipped with permanent magnets (a stationary magnet cup S integrated with the base C and a floating magnet cup F on the opposite side, into which the stationary winding group W is integrated). The magnets of the magnet cups S and F are arranged to generate a strong mutual attractive force between the two cups, and this attractive force is sufficient to maintain the rotational position of the winding group W in a stationary state, even without a mechanical connection to the base C and even with a rotational dragging effect on the winding group W by the shaft A.

[0027] The weft yarn coming from the supply spool (not shown) is inserted axially into the shaft A from the rear end of the weft supply device and exits to the outside through the inner channel P of the winding device G and an outlet opening formed on the periphery of the winding device G. As the winding device G rotates, the yarn taken from the spool is continuously wound onto the outer drum D of the winding group W.

[0028] As shown in the exploded view of Figure 2, the winding group W includes a stationary body 1 integrated with the floating cup F, an inclined body 2, and an adjustment group 3 interposed between the stationary body 1 and the inclined body 2. The inclined body 2 is directly supported by the shaft A and corresponds to an eccentric bush fixed on the shaft. The outer surface of this eccentric bush is given a moderate inclination of several degrees with respect to the axis of shaft A.

[0029] The stationary body 1 forms a weft supply device drum D on which the weft reserve is wound. The stationary body 1 is composed of a plurality (preferably at least four) of fixed members 5 having independent arched surfaces, each having a single support shank 5g, which is fixed to the stationary support disc 6 via the shank 5g. The stationary support disc 6 has a radial seat for the shank 5g of the fixed member 5, and the shank 5g is slidable radially and longitudinally to determine the operating position of the fixed member 5 when the weft supply device is operating at different weaving heights. [First Embodiment of the Invention]

[0030] A first important feature of the present invention is that the side walls of the shank 5g converge, preferably symmetrically. In this case, the shank 5g has a trapezoidal cross-section—preferably an isosceles trapezoidal cross-section—and as a whole has the shape of a trapezoidal right-angled prism. The radial seat of the shank 5g consists of a cavity of the same shape, and the main base and / or sub-base of the trapezoid may be partially open as needed. This allows for automatic centering and locking in a stable position when the shank 5g is pressed against the seat by elastic force by fitting the converging sides of the corresponding trapezoidal shape.

[0031] Except for the shape of the movable member 7, the structure of the inclined body 2 is exactly the same as that of the stationary body 1 described above, and includes the movable member 7. Each movable member 7 is equipped with its own shank 7g and is fixed to the inclined support disc 8. The inclined support disc 8 is rotatably and stably constrained to the free end of the weft supply device shaft A, corresponding to the eccentric bush. The inclined support disc 8 has a radial seat for the shank 7g of the movable member 7, and the shank 7g is slidable radially and longitudinally to determine the operating position of the movable member 7 when the weft supply device is operating at different weaving heights. The shank 7g of the movable member 7 is also in the shape of a trapezoidal right-angle prism, having a trapezoidal, preferably isosceles trapezoidal, cross section, and is housed in a seat of the same shape with one or both of two opposing bottoms partially open as needed. The shank 7g of the movable member 7 is positioned mirror-image to the shank 5g of the fixed member 5, and both shanks 5g and 7g have their sub-bottoms equipped with guide ribs facing towards the adjustment group 3.

[0032] When the stationary body 1 and the inclined body 2 are combined within the weft supply device, the finger-shaped member 7d of the movable member 7 is housed in a position corresponding to the large opening 5f of the fixed member 5, and the finger-shaped member 7d periodically protrudes during the swinging and tilting motion of the inclined body 2, thereby causing the weft winding body wound on the drum D to be lifted and advanced in stages.

[0033] As is well known, the radial positions of the fixed member 5 and the movable member 7 can be adjusted as desired, thereby changing the drum diameter D and altering the total length of weft yarn accumulated on the drum D. At the same time, the relative positional relationship between the fixed member 5 and the movable member 7 is kept constant, which is essential for the correct function of the movable member of the weft yarn supply device. This simultaneous adjustment is effectively performed by manually operating the pinion 4 of the adjustment group 3 in a known manner. The shape and operation of the pinion 4 are well known and not components of the present invention, so their details will be described later.

[0034] In the above-described weft supply device structure, the second novelty that characterizes the first embodiment relates to a device for locking shanks 5g and 7g at a desired operating position determined at any time by the adjustment group 3.

[0035] According to the present invention, as shown in detail in Figure 3, the shank 5g of the fixing member 5 is pressed against each trapezoidal cross-sectional seat by an elastic member having the shape of a stationary spring 10, preferably such as a wave spring or a cup spring. Preferably, the stationary spring 10 does not act directly on the shank 5g but acts via a flat and rigid stationary "shank pressing" ring 9, and the stationary spring 10 applies a predetermined compressive force to the stationary shank pressing ring 9. The stationary shank pressing ring 9 is attached at a predetermined distance by a stationary closing ring 11 of the stationary body 1, and provides a desired preload to the stationary spring 10. The amount of preload of the stationary spring 10 is optimized so that the stationary spring 10 provides a compressive force sufficient to hold the shank 5g in a stable locked position during the normal operation of the weft supply device. However, this locking force is kept low enough to allow the position of the shank 5g to be adjusted without reducing the preload of the stationary spring 10. In particular, the compressive force is greater than the minimum gripping force required to maintain the adjustment position of the shank 5g without change during the normal operation of the weft supply device, and less than the maximum gripping force required to allow the shank 5g to slide within the seat when the position of the fixing member 5 is adjusted by operating the adjustment group 3.

[0036] The stationary shank pressing ring 9 is preferably made of a low-friction metal material and evenly distributes the compressive force from the stationary spring 10 to all four shanks 5g, enabling smooth radial sliding of the shanks 5g when adjusting the drum diameter D. As described above, the shanks 5g have an isosceles trapezoidal cross-section and are housed in a seat made of a cavity of the same shape. Therefore, the appropriate compressive force that the stationary spring 10 applies to the main base of the trapezoidal cross-section of the shanks 5g (i.e., the weft supply device body side) creates a wedge effect in the fitting between each shank 5g and its seat, and the fitting remains completely stable even if there is stress that attempts to change the radial position applied to the fixing member 5.

[0037] The inclined body 2 has an identical configuration, which is shown in detail in Figure 4. In the inclined body 2 as well, the shank 7g of the moving member 7 is pressed against its respective seat by an inclined spring 13, such as a wave spring or a cup spring. Preferably, the inclined spring 13 does not act directly on the shank 7g, but acts via a flat and rigid inclined "shank pressing" ring 12, and the inclined spring 13 applies a predetermined compressive force to the inclined shank pressing ring 12. The inclined shank pressing ring 12 is attached at a predetermined distance by an inclined closing ring 14 of the inclined body 2, and provides the desired preload to the inclined spring 13. In the inclined body 2 as well, the amount of preload of the inclined spring 13 is optimized so that the spring provides sufficient compressive force to hold the shank 7g in a stable position during the normal operation of the weft supply device. At the same time, the position of the shank 7g can be adjusted without reducing the preload of the inclined spring 13. In particular, the compressive force is greater than the minimum gripping force required to maintain the adjustment position of the shank 7g without change during the normal operation of the weft supply device, and less than the maximum gripping force required to allow the shank 7g to slide within the seat when the position of the movable member 7 is adjusted.

[0038] Other technical features and operations of the inclined body 2 are the same as those described above for the stationary body 1, and will not be repeated here for brevity. Figure 4 also shows other well-known components, namely the rolling bearing 15 that supports the inclined body 2 on the hollow shaft A of the weft supply device, and the "reverse" button 16 that operates the pitch adjustment mechanism of the yarn winding body or reverses the rotation direction of the weft supply device. [Composition of the control group - Known technology]

[0039] As mentioned above, the stationary body 1 and the inclined body 2 are interconnected by the adjustment group 3. The structure and operation of this adjustment group are already known, and will be briefly explained with reference to Figure 5 in order to fully understand the operation of the weft supply device.

[0040] Adjustment group 3 has the following functions: The inclined body 2 is semi-rigidly connected to the stationary body 1, and while maintaining the correct relative positions of the fixed member 5 and the movable member 7, the inclined body 2 is allowed to freely perform inclined motion by an eccentrically inclined bush, thereby enabling the stepwise advance of the weft winding body on the weft supply device drum D. The radial movement of the fixed member 5 and the movable member 7 is synchronized to allow adjustment of the drum diameter D. • Maintain the correct positioning of the adjustable toothed ring and ensure that it always engages correctly with the corresponding teeth provided on the shank 5g of the fixed member 5 and the shank 7g of the movable member 7.

[0041] Adjustment group 3 includes a stationary adjustment ring 17 for adjusting the position of the fixed member 5, a tilt adjustment ring 18 for adjusting the position of the movable member 7, a rubber outer sleeve 19, a stationary disc guide 20 on the stationary body 1 side, a tilt disc guide 21 on the tilting body 2 side, and a rubber inner sleeve 22, and its structure and function are as follows. - The stationary adjustment ring 17 and the inclination adjustment ring 18 are rigid rings, and during synchronous rotation, the helical ribs on their sides act on the toothed shanks 5g and 7g, causing these shanks to slide radially. The inclination adjustment ring 18 further has internal teeth 18t, which mesh with the adjustment pinion 4 to control rotation in both directions. The stationary adjustment ring 17 is not directly controlled but is rotationally driven integrally with the inclination adjustment ring 18. - The external sleeve 19 integrates the stationary adjustment ring 17 and the inclination adjustment ring 18 by fitting its cylindrical side to the outer surface of the adjustment ring, thereby ensuring synchronized operation when adjusting the drum diameter. On the other hand, the central bellows section enables continuous inclination movement of the inclined body 2 during the operation of the weft supply device. - The stationary disc guide 20 on the stationary body 1 side is a plate integrally attached to the stationary support disc 6 of the fixed member 5, and ensures that the helical ribs of the stationary adjustment ring 17 always engage with the teeth of the shank 5g of the fixed member 5. - The inclined disc guide 21 on the inclined body 2 side is a plate integrally attached to the inclined support disc 8 of the movable member 7, and ensures that the spiral ribs of the inclination adjustment ring 18 always engage with the teeth of the shank 7g of the movable member 7. - The rubber internal sleeve 22 also has cylindrical sides and a central bellows section. The cylindrical sides integrate the stationary disc guide 20 and the inclined disc guide 21, and consequently the stationary support disc 6 and inclined support disc 8 of the fixed member 5 and the movable member 7. The function of the internal sleeve 22 is to prevent relative rotation between the stationary body 1 and the inclined body 2, while the central bellows section allows the inclined body 2 to move inclined, which is necessary for the correct operation of the group. [Second Embodiment of the Invention]

[0042] As stated at the beginning of this specification, a second embodiment of the present invention aims to increase the compressive force of an elastic member applied to the shanks of the fixed member and the movable member, and to enable operations in which high stress is applied to these members, and includes a locking device that allows the locking / unlocking operations of the fixed member 5 and the movable member 7 to be performed in a very short time. According to a third feature of the present invention, these locking devices are of the rapid tension type, have bistable operation between the locked position and the unlocked position, and are used in addition to the elastic member described in the first embodiment, for the purpose of changing its compressive force.

[0043] A preferred configuration example of these additional locking members according to a second embodiment of the present invention is schematically shown in Figures 6 to 8 with respect to the movable member 7. The movable member 7 is located outside the winding group W and is more easily accessible, so it is preferable to attach the locking member to the movable member 7. However, as will be described in detail below, a similar configuration can of course be attached to the fixed member 5 as well. In any case, once the locking member is attached to either the movable member 7 or the fixed member 5, both members are always held integrally by the adjustment group 3 and especially the internal sleeve 22, so both members are completely locked in the set position.

[0044] The structure of the inclined body 2 is identical to that described in the first embodiment, and therefore includes an inclined spring 13 such as a wave spring or a cup spring, which presses the moving member 7 to the seat via a flat and rigid inclined "shank pressing" ring 12. The compressive force of the inclined spring 13 is determined by applying a desired preload to the inclined shank pressing ring 12, which is mounted at a predetermined distance by the inclined closing ring 14 of the inclined body 2.

[0045] According to a third feature of the present invention, an inclined lock ring 23 is interposed between the inclined spring 13 and the inclined closing ring 14, and is mounted within the inclined body 2 so as to be able to rotate freely relative to both the inclined spring 13 and the inclined closing ring 14. As shown in Figures 7A and 8A, the mutually contacting sides of the inclined lock ring 23 and the inclined closing ring 14 are provided with contact surfaces 24 having various inclinations with respect to a plane perpendicular to the weft supply device axis, forming a wave-like shape with alternating irregularities. As a result, the axial thickness of the inclined lock ring 23 and the inclined closing ring 14 changes from a minimum to a maximum value on the circumference due to the wave-like shape.

[0046] In the second embodiment of the present invention, the rapid locking / unlocking operation of the movable member 7 is achieved simply by controlling the rotation of the inclined locking ring 23 relative to the inclined closing ring 14. During this rotation, the opposing contact surfaces 24 of the inclined locking ring 23 and the inclined closing ring 14 slide against each other, changing the axial position of the inclined locking ring 23 and, consequently, the preload of the inclined spring 13.

[0047] especially, When the opposing contact surfaces 24 overlap such that the recess of one surface corresponds to the protrusion of the other, the preload of the inclined spring 13 is minimized, allowing adjustment of the drum diameter of the moving member, while maintaining the minimum preload necessary for the moving member 7 and its associated fixing member 5 to be stably held within the seat during standard operation. When the opposing contact surfaces 24 overlap with each other's protrusions, the preload of the inclined spring 13 reaches its maximum value, and eventually the elastic force of the inclined spring 13 is removed, forming a high clamping force, or ultimately a highly rigid connection, between the inclined closing ring 14 and the inclined shank pressing ring 12.

[0048] Finally, the inclined lock ring 23 is provided with projections 25 that protrude radially inward. These projections 25 engage with corresponding end stop portions 28 (see Figures 8 and 8A) formed on the inner portion of the inclined closing ring 14, thereby limiting the rotation range of the inclined lock ring 23. This ensures that the relative position of the two opposing wavy contact surfaces 24 is reliably guaranteed during the adjustment stage of the weft supply device drum diameter (adjusted fitting of the minimum and maximum height portions of the opposing contact surfaces 24) and the operation stage of the weft supply device (fitting of the maximum height portions of the opposing contact surfaces 24).

[0049] The projection 25 of the inclined lock ring 23 is provided with a retaining hole 26 into which a special control lever (not shown) can be inserted. These control levers are inserted through an arched access opening 27 formed in the inclined closing ring 14. The control levers assist the operator in adjusting the weft supply device when manual operation of the outer surface of the inclined lock ring 23 alone does not provide enough force to switch the weft supply device from the adjustment position to the operating position or vice versa.

[0050] In the weft supply device according to the second embodiment of the present invention, by appropriately setting the dimensions of the contact surface 24, the force required for the lock / unlock operation by operating the inclined lock ring 23 and the residual force acting on the member (the height difference of the opposing contact surfaces 24 at the locked position and the unlocked position is inversely proportional to the residual force acting on the member) can be precisely controlled.

[0051] As described above, by adopting a similar configuration, a rapid-acting fastener can also be provided on the fixed member 5 (in place of or in addition to the one for the movable member 7). In this case, a stationary locking ring (not shown) is inserted between the stationary spring 10 and the stationary closing ring 11, and wavy opposing contact surfaces are provided on both. The rotation of the stationary locking ring, which controls the locking / unlocking of the fixed member 5, can be controlled by operating the stationary locking ring from the side or by a holding lever that protrudes from the second pair of arch-shaped openings of the closing ring 14 through the central cavity of the weft supply device.

[0052] The diameter of the weft supply device drum is adjusted by operating the pinion 4 of adjustment group 3, similar to the system described in the previous section.

[0053] In the weft supply device according to the second embodiment of the present invention, the rapid tension fastener is normally held in the unlocked position and can therefore operate in exactly the same manner as in the first embodiment. However, if necessary (for example, in heavy weaving processes or when wear or malfunction occurs where it is important to maintain the stable position of the fixed member 5 and the movable member 7), the rapid tension fastener can be activated very easily and quickly to stably lock the fixed member 5 and the movable member 7 in the desired operating position.

[0054] From the above description, it is clear that the present invention has fully achieved all its objectives. However, it should be understood that the present invention is not limited to the specific configurations illustrated above, as these are merely exemplary embodiments, and various modifications that are feasible for those skilled in the art can be implemented without departing from the scope of protection of the present invention. The scope of protection of the present invention is defined solely by the following claims. [Explanation of symbols]

[0055] A Hollow shaft C base D Drum F Floating Magnet Cup G Winding device M electric motor P Winding device channel S Stationary Magnet Cup W Winding Group 1. Stationary object 2 Inclined bodies 3 Adjustment group 4 Adjustable pinion 5 Fixing members 5f Fixing member opening 5g Support shank for fixing member 6. Static support disk 7. Movable member 7d Finger-shaped member of the movable member 7g Support shank for movable member 8. Inclined support disc 9. Stationary shank pressing ring 10 Static springs 11. Static closed ring 12 Inclined shank pressing ring 13 Inclined spring 14. Inclined closure ring 15 Rolling bearings 16. Invert button 17. Static adjustment ring 18 Tilt adjustment ring 19 External sleeve 20 Static Disc Guide 21. Inclined Disc Guide 22 Internal sleeves 23 Inclined lock ring 24 Inclined contact surface 25 Protrusion 26 grip holes 27 - Access opening 28 - End stop

Claims

1. A weft supply device for a loom having spaced-apart spindles and a drum with an adjustable diameter, wherein the drum is formed of a plurality of fixed members, each of the plurality of fixed members comprising a support shank housed in a seat formed in a stationary support disc coaxial with the drive shaft of the weft supply device, the spacing of the spaced-apart spindles on the drum is caused by vibration and tilting motion of a plurality of movable members, each of the plurality of movable members comprising a support shank housed in a seat formed in a tilting support disc, an elastic member that applies compressive force to the shank is provided to hold the fixed member and the movable member in a position where they are stably engaged within their respective seats, each of the fixed member and the movable member comprising a single support shank having the general shape of a trapezoidal right-angle prism housed in a seat formed in a cavity having a congruent trapezoidal shape, limited by at least the spread of converging side walls, and the elastic member applies compressive force to the main base of the support shank having the general shape of a trapezoidal right-angle prism.

2. A weft supply device for a loom according to claim 1, wherein the support shanks of the fixed member and the movable member are in the shape of an isosceles trapezoidal right-angle prism.

3. A weft yarn supply device for a loom according to claim 1 or 2, wherein the sub-base of the support shank, which is in the shape of a trapezoidal right-angled prism, includes a plurality of members, and the plurality of members guide the longitudinal movement of the plurality of members and control the respective positions within the plurality of members.

4. A weft supply device for a loom according to any one of claims 1 to 3, wherein the compressive force is The gripping force is greater than the minimum gripping force required to maintain the adjustment position of the support shank in a state where it does not change during the normal operation of the weft supply device, and In the operation of adjusting the positions of the fixed member and the movable member, the gripping force is less than the maximum force at which the support shank can still slide within each seat of the support shank. A weft yarn supply device for a loom.

5. A weft supply device for a loom according to any one of claims 1 to 4, further comprising a bistable rapid tension fastener between a locked position and an unlocked position for adjusting the compressive force exerted by the elastic member on the support shank.

6. The weft supply device for a loom according to claim 5, wherein the adjusted compressive force is In the locked position, the gripping force is greater than the minimum gripping force required to maintain the adjustment position of the support shank in a state where it does not change under any operating conditions of the weft supply device, and In the unlocked position, the gripping force is less than the maximum gripping force that allows the support shank to still slide within each seat of the support shank during the operation to adjust the positions of the fixed member and the movable member. A weft yarn supply device for a loom.

7. A weft supply device for a loom according to any one of claims 1 to 6, wherein the elastic member includes a wave spring or cup spring that acts on the support shank of the fixed member and the movable member under conditions of a specific preload applied by a closing ring.

8. A weft supply device for a loom according to claim 7, further comprising a flat, rigid shank pressing ring interposed between the elastic member and the support shank of the fixed member and the movable member.

9. A weft supply device for a loom according to claim 5 or 6, wherein the rapid tension stopper includes a locking ring interposed between the elastic member and the closing ring and freely rotating between the elastic member and the closing ring, and the opposing surfaces of the locking ring and the closing ring are wavy contact surfaces that cooperate to change the axial position of the locking ring between a distant position and a position close to the closing ring during rotation, thereby changing the preload to the elastic member.

10. A weft supply device for a loom according to claim 9, wherein the lock ring is provided with a projection that determines a rotation limiting position against a corresponding end stop portion formed within the closing ring.

11. A weft supply device for a loom according to claim 10, wherein the projection is provided with a retaining hole that engages with a control lever.

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