US3788360A

US3788360A - Weft needle head of shuttleless loom

Info

Publication number: US3788360A
Application number: US00240077A
Authority: US
Inventors: M Guallo
Original assignee: ATELIERS DIEDERICKS
Current assignee: ATELIERS DIEDERICKS
Priority date: 1971-04-05
Filing date: 1972-03-31
Publication date: 1974-01-29
Anticipated expiration: 1991-01-29
Also published as: FR2132560B1; JPS52157B1; GB1354654A; CA951997A; SU436503A3; DD96519A5; DE2214813C3; FR2132560A1; BE780929A; DE2214813B2; DE2214813A1; ES401214A1; CS182767B2; CH544169A; IT950328B

Abstract

This head of weft-yarn introducing needle for a shuttleless loom, which is adapted to introduce the yarn into the shed by developing a yarn loop having one end retained and the other end released, comprises a parallelipipedic tubular body of substantially rectangular cross-sectional configuration with horizontal walls formed with notches ; these notches have their bottom lined preferably with a ceramic material with their two pointed ends slightly recessed in relation to the notch bottom inlets ; on the feed side, the horizontal wall of the head adjacent the free end of the yarn loop is skew to the direction of travel and the wall portion bounded by the edge of said notch and the rear edge form together an upswept curved tongue terminating at a certain distance from the contiguous vertical wall.

Description

United States Patent Guallo Jan. 29, 1974 1 WEFT NEEDLE HEAD OF SHUTTLELESS Primary Examiner-Henry S. Jaudon LOOM [75] Inventor: Maxime Guallo, Bourgoin-Jallieu,

France [73] Assignee: Ateliers Diedericks,

Bourgoin-Jallieu, France [22] Filed: Mar. 31, 1972 [21] Appl. No.: 240,077

[30] Foreign Application Priority Data Apr. 5. 1971 France ..7l.l2626 [52] U.S. Cl 139/122 N [51] Int. Cl D03d 47/20 [58] Field of Search 139/122 N [56] References Cited UNITED STATES PATENTS 3,299,910 1/1967 Flamand 139/122 3,081,796 3/1963 Remington 139/122 Attorney, Agent, or FirmEric H. Waters et a1.

[57] ABSTRACT This head of weft-yarn introducing needle for a shuttleless loom, which is adapted to introduce the yarn into the shed by developing a yarn loop having one end retained and the other end released, comprises a parallelipipedic tubular body of substantially rectangular cross-sectional configuration with horizontal walls formed with notches these notches have their bottom lined preferably with a ceramic material with their two pointed ends slightly recessed in relation to the notch bottom inlets on the feed side, the horizontal wall of the head adjacent the free end of the yarn loop is skew to the direction of travel and the wall portion bounded by the edge of said notch and the rear edge form together an upswept curved tongue terminating at a certain distance from the contiguous vertical wall.

6 Claims, 6 Drawing Figures PATENTEDJAN 29 I974 l 1 l l I FiG.6

WEFT NEEDLE HEAD OF SHUTTLELESS LOOM FIELD OF THE INVENTION This invention relates in general to shuttleless looms and has specific reference to improvements in or relating to weft yarn introducing needle heads for such looms. In these looms, the weft yarn is introduced into the shed by means of a pair of needles by developing a yarn loop having one end retained and the other end released, one of said needles being the introducing needle located on the feed side, adapted to introduce the double yarn as far as the middle of the cloth width, the other needle being the traction needle and travelling in a direction opposite to that of said first needle so as to deposit in the shed, in the second half of the cloth width and after having picked up the loop, the previously released yarn end.

DESCRIPTION OF THE PRIOR ART In looms of this general type it is well known to use as a head of the introduction needle a tubular parallelipipedic body of substantially rectangular cross sectional, wherein each horizontal wall has a notch opening substantially in the direction of the weft introduction, the weft yarn being caused to slip in the bottom of this notch during its insertion into the first half of the width and, as a head of the traction needle, a hook adapted, at the end of its stroke, to penetrate into the tubular body of the introduction needle for picking up the yarn loop and depositing the released yarn end into the shed.

The heads of introduction needles of the abovedescribed type are objectionable in that they are sometimes the cause of weft yarn breakage for, after the transfer of the yarn loop from one needle to the other needle the end of the free weft yarn section which is positioned between the introduction needle head and the feed and travels at twice the speed of this needle head and in the opposite direction, wriggles at random and may at least partially penetrate in the form of a small loop into the aforesaid introduction needle head, on the open feed side thereof. To emerge therefrom, the free yarn end must slip over the rear edge, thus increasing considerably the resistance to the normal movement and therefore the tractive effort exerted on the weft yarn, which may even exceed permissible limits.

Another inconvenience observed with introduction of needle heads of the above type, is that the edges of the notch bottoms over which the weft yarn is caused to slip during its introduction into the shed must be carefully rounded. However, this constitutes a difficult and costly operation, inasmuch as the walls preferably are of relatively thin sheet material.

Besides, in the long run the yarn may wear these edges.

SUMMARY OF THE INVENTION It is an object of this invention to provide a needle head which avoids these various inconveniences.

To this end and according to the present invention, the edge, on the feed side, of the wall of the head of the introduction needle disposed on the side of the free length of weft yarn is skew in relation to the direction of travel, and the portion of this wall which is bounded by the edge of the notch and said edge on the feed side constitutes a tongue terminating at a certain spacing from the contiguous vertical wall, thus leaving between this vertical wall and said tongue a release gap for the weft yarn.

In order to eliminate any risk of catching the warp yarn when the latter moves into the path followed by the needle head, the vertical walls of this needle head terminate in the form of points converging in the direction of the introduction of the weft yarn, in a manner known per se, and the tongue end is directed towards the contiguous vertical wall, its end being located ahead and above the longitudinal edge, its other edge on the notch side being co-extensive with the point of said vertical wall.

To reduce the resistance to the slipping movement of the yarn and the wear of the notch bottoms, each notch bottom is provided with a hardened rounded bead consisting advantageously of a crescent-shaped ceramic lining having an outer contour smaller than that of the notch itself, said lining being fitted into said notch in such a manner that its two pointed ends are slightly recessed with respect to the inlet of the notch bottom to avoid any risk of catching the yarn.

A clearer understanding of this invention will be had if reference is made to the attached drawing showing diagrammatically by way of illustration a typical embodiment wherein the free end of the yarn loop underlies the head of the introduction needle.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a side elevational view of the needle head in a position prior to transfer of the yarn;

FIG. 2 is a plan view from above of the same needle head;

FIG. 3 is a view similar to FIG. I but showing the free end of the weft yarn loop as it clears the release gap;

FIG. 4 is a view similar to FIG. 2 but with the weft yarn loop in the position of FIG. 3;

FIG. 5 is a front elevational view of the needle head, and

FIG. 6 is a fragmentary detail view, showing on a larger scale, the abrasion-resistant linings of said notch.

DESCRIPTION OF THE PREFERRED EMBODIMENT In the drawing, the reference numeral 1 designates the needle body or head-carrier to which the yarn introducing head is secured, for example, by means of rivets 11. The top wall of the needle head is designated by the reference numeral 2, and, numeral 3 is the bottom wall,

numerals

4, 5 being the two vertical or side walls terminating each, on the introduction side, with a pointed portion as shown at 40 and 5a, respectively. This pointed portion 5a, as already known in the art, is slightly off-set to constitute an outflaring portion adapted to facilitate the penetration of the hook element of the traction needle.

At its feed end, the bottom wall 3 is cut obliquely, the skew edge 3a extending from the vertical wall 4 to which this bottom wall is connected and said skew edge 3a terminates beyond the other vertical wall 5 to which said bottom wall is not connected.

On its introduction side, the bottom wall 3 is cut obliquely, the reference numeral 30 designating the skew edge extending from the vertical wall 4 and directed in opposition to said edge 3a in relation to the direction of travel of the needle. This edge 30 extends angularly with respect to another intersecting skew edge 3d having the same direction of inclination as said edge 3a. This other edge 3d forms with edge 3c a projection constituting somewhat the extension of point 40, and, with another skew edge 3e less inclined than the first one in relation to the direction of travel, a notch 12 in which the weft yarn inserted vertically during the feed is introduced at the beginning of each pick positioning as shown in FIG. 1.

The bottom wall portion bounded by the edge 3a on the feed side and by the edge 32 of the notch forms a tongue whose tip 3b is upswept and terminates slightly above and ahead of the edge b of vertical wall 5, thus leaving a free gap 6. The upper wall 2, as seen in the drawing, is connected to

vertical walls

4 and 5 and is formed with a notch aligned with the notch 12 in the bottom wall to allow passage of the weft thread. The edges of the notch in the upper wall are shown with reference numerals 2c, 2d in FIGS. 2 and 4.

The upper and lower walls are provided with crescent-shaped linings which are mounted at the bottom of the notches and whose external countour is shorter than the notch bottom, these linings being so fitted that their points 10a are somewhat recessed with respect to the edges of the notch bottoms. Preferably, these linings consist of ceramic material and are properly rounded to resist wear and reduce frictional contacts.

The reference numeral 8 designates the free end of the weft loop adapted to be pulled in the direction of the arrow 7 by the hook element of the other needle (not shown), 8a designating the end of the free yarn section extending behind the introduction needle head. The needle head travels in the direction of the arrow 13.

The needle head according to this invention operates as follows:

At the time of introduction into the shed of the needle head, it is displaced in the direction of the arrow 7. At the beginning of this movement the thread is in the path of said needle head and is engaged between the two

walls

4 and 5 to penetrate into the notches 12 to reach the bottom of the two linings 10. The extremity of the thread 8a of the yarn is retained in the selvedge of the material and the other end 8 is pulled and unwound from the supply bobin. This is the arrangement as seen in FIG. 1. After transferring the weft loop from the introduction needle to the traction needle, the

free end

8, 8a remains in line and spaced from the introduction needle for a certain time. When the speed of the needle heads, during the return stroke, has attained a predetermined value, the free end, whose speed is twice the head speed, begins to wriggle. The end 8a is thus caused to move at random and jumps forwards, thus forming small loops 9 accumulating on the feed side within the head. Due to the inclination of edge 3a, the yarn pulled by the hook element of the traction needle slips along the tongue and escapes through the gap 6 left unobstructed between this tongue and the vertical wall 5, without undoing the loops 9. Then the end 8a passes into the head as shown in FIGS. 3 and 4.

Of course, this invention should not be construed as being strictly limited to this specific form of embodiment since many modifications may be brought thereto without departing from the basic principle of the invention as set forth in the appended claims.

What is claimed as new is:

1. A needle head for introducing weft thread into shuttleless looms in which the weft thread is introduced into a shed by developing a loop having one end retained and the other end released, said needle head comprising a tubular parallelepiped body of substantially rectangular cross-section with spaced vertical walls, and upper and lower horizontal walls each having a notch bounded by two inclined edges, the weft thread being adapted to slide in said notches before being transferred to a traction needle head, said lower wall having an edge inclined at an angle with respect to the direction of movement of the head, the latter said edge joining with one edge of the notch formed in the lower wall by a projecting part constituting a tongue which is spaced from the contiguous vertical wall of the needle head to form a gap with this wall for passage of the weft thread.

2. A needle head as claimed in claim 1, wherein said tongue is bent upwardly from said lower wall to face the contiguous vertical wall.

3. A needle head as claimed in claim 2, wherein said tongue includes a tip portion which extends above the level of the lower edge of the contiguous vertical wall.

4. A needle head as claimed in claim 1, wherein each vertical wall includes a V-shaped forward terminal portion which narrows in the direction of introduction of the head into the shed, said tongue including a tip portion which is located above the lower longitudinal edge of the contiguous vertical wall.

5. A needle head as claimed in claim 4, wherein said tip portion has an edge which is in alignment with an edge of the V-shaped portion of the contiguous vertical wall.

6. A needle head as claimed in claim 1, comprising crescent-shaped ceramic linings mounted on each horizontal wall at each notch therein, said linings having a smaller external contour than that of the respective notches, said linings being fitted into the bottom of said notches and having two pointed ends which are slightly recessed in relation to inlets of the notch bottoms.