US3863822A

US3863822A - Nozzle device for producing a fluid jet

Info

Publication number: US3863822A
Application number: US356103A
Authority: US
Inventors: Rachid Keldany
Original assignee: Maschinenfabrik Rueti AG
Current assignee: Maschinenfabrik Rueti AG
Priority date: 1972-05-29
Filing date: 1973-05-01
Publication date: 1975-02-04
Anticipated expiration: 1992-02-04
Also published as: BR7303619D0; CH545364A; CS175457B2; BE800113A; JPS4926569A; FR2186849A5; DE2226622A1; IT972926B; JPS5227753B2; SU478466A3

Abstract

The present invention relates to a nozzle device for producing a jet of a fluid for the insertion of weft threads into a shed on a loom, the nozzle device comprising an inner portion and an outer portion surrounding the inner portion, there being provided between the inner portion and the outer portion a chamber which contains a fluid, which chamber is rotationally symmetrical about the axis of the nozzle, and which chamber has apertures therein for supplying the fluid and a fluid exiting nozzle aperture surrounding a bore through which the weft thread passes propelled by said fluid as it exits from said nozzle aperture.

Description

United States Patent i191 Keldany Feb. 4, 1975 [54] NOZZLE DEVICE FOR PRODUCING A 3,559,860 2/1971 East 226/97 FLUID J 3,576,284 4/1971 Fellows 226/97 3,633,808 l/l972 Svaty 226/97 [75] Inventor: Rachld e any, ri 3,655,862 4/1972 Dorschner et al. 226/97 Switzerland [73] Assignee: Ruti Machinery Works Ltd., Primary Examiner-Allen N. Knowles (formerly Caspar Honegger), Attorney, Agent, or Firm-Donald D. Denton Ruti/ZH', Switzerland [22] Filed: May 1, 1973 [57] ABSTRACT [21] Appl. No.: 356,103 I The present invention relates to a nozzle device for producing a jet of a fluid for the insertion of weft [30] Foreign Application Priority Data threads intoa shed on a loom, the nozzle dev ce comprising an inner portion and an outer portion sur May 29, i972 Switzerland 7395/72 rounding the inner portion, there i g p id r tween'the inner portion and the outer portion a chame I erw 1C contalnsa u ,.W C c am er ,5 tat 2% F 8 b h'h fl'd h'h h b l 5 ally symmetrical about the axis of the nozzle, and 1 0 care l which chamber has apertures therein for supplying the 19/66 T fluid and a fluid exiting nozzle aperture surrounding a References Cited bore through which the weft thread passes propelled by said fluid as it exits from said nozzle aperture.

8 Claims, 2 Drawing Figures PATEMED 7 3,863,822

VELOCITY CHAMBER LEN GTH NOZZLE DEVICE FOR PRODUCING A FLUID JET BACKGROUND It is known to insert weft threads into an open shed, as individual picks, by means of a jet of air or water. This type of weft insertion, employing means known at the present day, has the disadvantage that any sharply focused" jet which can be produced can have only limited length, so that broad fabrics cannot be manufactured in this manner.'Art which shows the use of air and water jets are disclosed in the following patents:

US. Pat. No. 2,796,085 US. Pat. No. 3,l80,368.

SUMMARY This disadvantage is obviated by the present invention. The present invention is characterized in that the chamber has between the inner portion and the outer portion of the nozzle device, extending rearwardly away from the nozzle aperture, an alignment or "aiming" portion which determines the direction of the jet and which is prolonged in the form ofa storage portion, the apertures for supplying the fluid to the chamber being located in the chamber zone remote from the nozzle aperture.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will now be described with reference to an example of embodiments and with reference to the drawings, in which:

FIG. 1 is a longitudinal section through the nozzle device which is symmetrical in shape; and

FIG. 2 illustrates the important features of the chamber containing the fluid, the velocity distribution of the fluid in the chamber also being shown.

DESCRIPTION OF PREFERRED EMBODIMENTS The nozzle device 11 shown in FIG. 1 has a jet or nozzle needle 12 affording an inner part or portion. The nozzle needle or inner portion 12 is surrounded by an outer part or portion which, according to this example of embodiment, embraces a nozzle insert 13 and a nozzle head 16. A securing screw or threaded cap 32 is also provided. The inner portion 12, the nozzle insert 13, and the nozzle head 16 of the outer portion constitute, or define together, a fluid chamber 14. Apertures 15 serve for feeding a fluid from a fluid supply zone 15a into the chamber 14. A fluid supply source not shown conveys the fluid to the supply zone 15a through fluid supply conduit 15b from a standard fluid feeding device 150. The nozzle insert 13 and the nozzle needle 12 are united and held in operation position by means of the nozzle head 16 and the securing screw 32. The screw 32 is adapted to be screwed through the agency of the screw thread 33 to threaded portion of head 16. When the securing screw is in a tightened condition, the nozzle insert presses against packings I7 and provides for preventing the escapement ofthe fluid out of the nozzle device 11. The nozzle device can be secured to the loom by means ola support rod 19. The nozzle needle 12 is rotatable about a pivot line 18 relative to the nozzle insert 13 and, optionally, also the nozzle head 16 along the said pivot line 18. A weft thread is guided through the bore 20 formed in the nozzle needle 12. As is shown in FIG. 1, the nozzle needle I2 is adapted to be inserted into the nozzle insert 13 from the left-hand side.

The fluid chamber 14 is symmetrical in rotation and comprises a storage portion and an aligning or aiming" portion, the longitudinal sections of which are delimited by

walls

21, 22 and by curved portions of

walls

23, 24. In the direction of the axis 18, delimitation of the storage portion is afforded approximately by dashed boundary lines 25, 26, and delimitation of the guiding portion by dashed

boundary lines

26, 27. An annular nozzle aperture 28 formed between the adjacent inside portion of nozzle insert I3 and the outside portion of the needle nozzle 12 coincides with the boundary line 27 through which the fluid exits as a jet from said chamber. An eyelet 30 may be provided with a small degree of spacing from the nozzle aperture 28.

The design of the nozzle is discussed further in detail with reference to FIG. 2. In the portion of FIG. 2 designated as A, the curved portions of

walls

23 and 24 extending between the

boundaries

26 and 27 are represented as component portions of

parabolic curves

31 and 32 in their flow pattern, the foci of which are displaced in the axial direction. Thus, it may be said that the opening of the aligning portion toward the nozzle aperture 28 diminishes continuously by values becoming progressively smaller. Toward the left, away from the boundary line 26, the delimiting

portions

21, 22 of the cross-section of the storage part of the chamber 14 extend rectilinearly. Each of the

walls

21, 22 forms a

tangent

21 and 22, respectively, in each instance to one of the parabolas 31 and 32 (see A of FIG. 2).

The chamber 14 is symmetrically rotational in shape, the delimiting portions of which follow a configuration which is rectilinear in respect of the

wall

21, 22 and curved in respect of the

parabola portions

23, 24. If a fluid, for example a liquid, is routed through the apertures 15 into the chamber 14, and through the latter, then the velocity pattern of the liquid is that represented by the curve 33 in the portion B of FIG. 2. The velocity is plotted in B of FIG. 2 as ordinate, as a function of location, taken in the direction of the axis 18. It will bev appreciated that, directly at the boundary line 26, the acceleration of the fluid increases and that it reaches its maximum value between the

boundary lines

26 and 27.

On inserting the weft threads by the nozzle device into the shed, high pressure is for a short time imparted to the liquid. Thereby, it flows through the apertures 15 into the chamber 14 conveyed by fluid feeding device 15c, whereby a jet is emitted out of the nozzle aperture 28 for a short period of time. The said jet of fluid engages the weft thread inserted through the bore 20 around its periphery, entrains it and inserts it into the shed. That quantity of liquid already available in the chamber 14 on commencement of the increase in the fluid pressure undergoes no noticeable change in direction in respect of its movement, so that the minimum of turbulence is set up in it, the result of this being an extremely uniform jet travelling at extremely high velocity, which propels the weft thread into the shed. The liquid flowing in through the apertures 15 must, on the other hand, be deflected from the very outset, whereby there may be produced turbulent streams which could be detrimental to the formation of a uniform jet. Thus, in a preferred embodiment of the present invention, the volume of the chamber 14 is so calculated that it is at least approximately equal to the quantity of liquid required for inserting an individual pick.

On the other hand, it is also possible to design only the curved portion 24 to be parabolic and thedelimiting portion 23 to be rectilinear. There is then obtained a shape of the chamber 14 the longitudinal section of which has the straight portion 35. The latter may, at the location of the nozzle aperture 28, be the tangent to the curve 31 according to the first embodiment. The advantage of a nozzle having an inner wall, the longitudinal section of which is rectilinear, consists in that such a nozzle is less expensive to manufacture .and nevertheless affords a jet of high quality.

The design of the walls of the chamber 14, in particular in the vicinity of the nozzle aperture 28, must be effected with maximum accuracy. In order to be able to compensate for any small deviations within the bounds of the degree of accuracy achievable, the nozzle needle 12 and the nozzle insert 13 are rotatable about the pivot 18 relative to each other. This may for example be effected by loosening the releasable screw 32 and, thereupon, manually rotating the front portion 34 of the nozzle insert 13. After the optimum setting has been found, the portions 12, 13 are locked by retightening the screw 32.

In order to still further improve the jet emerging out of the nozzle 28, the edges of the material'at the location of the delimiting portion 27 may be deactivated so that there is no turbulance as the fluid flows out of the annular opening formed by the nozzle aperture.

It will be appreciated that the nozzle according to the present invention is suitable above all for a jet of liquid. However, also in the event of employment ofa gaseous fluid, the nozzle according to the invention produces a jet which is sharply focused over a considerable length.

This disclosure of preferred embodiments and modifications of the invention is to be interpreted as illustrative of forms the invention may take and other modifications will readily occur to those skilled in the art. The invention is not to be restricted except by the scope of the appended claims wherein the novel features desired to be protected by Letters Patent are set forth.

What is claimed is:

l. Nozzle device for producing a jet of fluid for inserting weft threads into a shed on a loom, the said nozzle device comprising an inner portion and an outer portion symmetrically surrounding said inner portion, said inner and outer portions defining a ring shaped nozzle aperture for ajet of fluid to flow out, there being defined between the said inner portion and the said outer portion a chamber which contains the weft thread propelling fluid, said outer portion being formed with a plurality of apertures for supplying the fluid to said chamber from a fluid source, said chamber having a front and a rear zone with its front zone extending rearwardly away from said nozzle aperture and forming an aiming" portion for determining the direction of the flow of'said jet of fluid, and which is prolonged by said rear zone forming a storage portion, the apertures for supplying the fluid to said chamber being located in said rear zone remote from the nozzle aperture, said aiming portion being elongated and delimited by two walls at least one of which is conical and that converge with respect to each other to produce a substantially uniform decrease in the cross-section of the aiming portion in'the direction of the nozzle aperture, a bore in said inner portion for passage of said weft thread to be propelled by said jet of fluid passing from said nozzle aperture, and a means for supplying said fluid flow to said chamber.

2. Nozzle device according to claim 1 in which the delimiting of the aiming portion by said two walls produc'es a configuration of the flow velocity pattern which is defined by two parabolas that are offset relative to each other in the axial direction.

3. Nozzle device according to claim 1 in which the I storage portion is delimited by two walls including an acute angle with the nozzle axis and approaching each other in the direction towards the nozzle aperture.

4. Nozzle device according to claim 1 for the insertion of weft threads by means of a liquid, in which the volume of said chamber is at least approximately equal to the volume of the quantity of liquid required for the insertion of the weft thread being drawn through said bore.

5. Nozzle device according to claim 1 in which the inner portion and the outer portion are rotatable relative to each other.

6. Nozzle deviceaccording to claim 5 in which said chamber is formed by the outer surface of the inner portion and the inner surface of the outer portion, and the inner portion is adapted to be inserted in the axial direction into the outer portion and is adapted to be held firmly in relationship to the outer portion by means of a releasable securing screw.

7. Nozzle device according to claim 1 in which the foremost delimiting portions of the nozzle aperture are constituted by deactivated edges.

8. Nozzle device according to claim 1 in which the two walls that delimit the storage portion are continued rectilinearly from the locations of the transition to the aiming portion and abut tangentially with the walls of the aiming portion.

Claims

1. Nozzle device for producing a jet of fluid for inserting weft threads into a shed on a loom, the said nozzle device comprising an inner portion and an outer portion symmetrically surrounding said inner portion, said inner and outer portions defining a ring shaped nozzle aperture for a jet of fluid to flow out, there being defined between the said inner portion and the said outer portion a chamber which contains the weft thread propelling fluid, said outer portion being formed with a plurality of apertures for supplying the fluid to said chamber from a fluid source, said chamber having a front and a rear zone with its front zone extending rearwardly away from said nozzle aperture and forming an ''''aiming'''' portion for determining the direction of the flow of said jet of fluid, and which is prolonged by said rear zone forming a storage portion, the apertures for supplying the fluid to said chamber being located in said rear zone remote from the nozzle aperture, said aiming portion being elongated and delimited by two walls at least one of which is conical and that converge with respect to each other to produce a substantially uniform decrease in the cross-section of the aiming portion in the direction of the nozzle aperture, a bore in said inner portion for passage of said weft thread to be propelled by said jet of fluid passing from said nozzle aperture, and a means for supplying said fluid flow to said chamber.

2. Nozzle device according to claim 1 in which the delimiting of the aiming portion by said two walls produces a configuration of the flow velocity pattern which is defined by two parabolas that are offset relative to each other in the axial direction.

3. Nozzle device according to claim 1 in which the storage portion is delimited by two walls including an acute angle with the nozzle axis and approaching each other in the direction towards the nozzle aperture.

6. Nozzle device according to claim 5 in which said chamber is formed by the outer surface of the inner portion and the inner surface of the outer portion, and the inner portion is adapted to be inserted in the axial direction into the outer portion and is adapted to be held firmly in relationship to the outer portion by means of a releasable securing screw.