Classifications

• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03C—SHEDDING MECHANISMS; PATTERN CARDS OR CHAINS; PUNCHING OF CARDS; DESIGNING PATTERNS
  • D03C7/00—Leno or similar shedding mechanisms
  • D03C7/02—Gauze healds
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D19/00—Gauze or leno-woven fabrics
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D3/00—Woven fabrics characterised by their shape
  • D03D3/02—Tubular fabrics
• • D—TEXTILES; PAPER
  • D03—WEAVING
  • D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
  • D03D37/00—Circular looms

Definitions

• the invention relates to a circular loom to manufacture doup fabric.
• a circular loom to manufacture doup fabric.
• doup fabric circular looms provided with heald assemblies to achieve high speed weaving.
• Doup fabric is of importance for producing light weight fabric with suitable ventilation of product.
• two neighbouring warp threads no longer lie parallel next to each other, but the so-called doup thread loops or crosses the other warp thread, here referred to as the ground thread, in such a way that the weft threads are bound in unable to slip.
• the object of the invention is to arrange and guide the oppositely-phased up-and- down-moving partial healds in such a way that after each shed-forming alternating motion, the two interacting weft threads permit a reciprocal displacement of one end.
• Another object of invention is to provide a partial heald that has longer service life.
• a further object of the invention is to provide a lateral displacement system for the partial heald that is able to operate at a high speed of the modern doup looms with minimal maintenance.
• the invention relates to a circular loom to manufacture doup fabric (F).
• a circular loom to manufacture doup fabric (F) in particular it relates to circular looms provided with plurality heald assemblies to achieve high speed weaving.
• the circular loom for producing endless tubular doup woven fabric (F) basically consists of the main frame on which the main motor driving the shedding cam and swing control cam are mounted; it also propels the shuttles on the endless reed (14).
• a partial healds belt assembly which facilitates displacement of the interacting warp threads is provided on the loom.
• the warp threads of at least one of the pair of partial healds (4, 5), which are provided with thread eyes (3) through which the threads pass, are guided freely by thread guide means to bring about the shedding, and, on the other partial heald, to bring about a side change.
• the eyes (3) are provided with a ceramic insert (3 A).
• the lateral movement needed to create the doup fabric (F) facilitated by a swing control cam (6B) that pushes the swing control cam roller (6A) against the torsion spring (13) mounted with swivel bush (12) resulting in the swinging motion of swivel arm (11).
• the swivel bush (12) is made of metallic material. LIST OF FIGURES
• Figure 1 shows a perspective view of the assembled heald belt assembly of the invention
• Figure 2 shows a schematic of the movement of the assembled heald belt assembly of the invention
• Figure 3 shows a circular loom fitted with the partial heald assembly of the invention
• Figure 4 shows the doup weave tubular fabric portion
• the circular loom for producing endless tubular doup woven fabric basically consists of the main frame on which the main motor (not shown in figures) driving the shedding cam (7B) and swing control cam (6B) is mounted; it also propels the shuttles (not shown in figures) on the endless reed (14).
• the take-up drive and motor are mounted on the top frame while the warp let-off drive and motor is mounted on both side frame (not shown in figures).
• Each system drive has individual motor and are controlled through central electronic control unit.
• the aforementioned objects are met by providing a plurality of partial healds belt assembly around the main frame circumference which facilitates displacement of the interacting warp threads.
• the partial healds belt assembly comprises (see Figure 1 for the perspective view) a pair of partial healds - partial heald-A (4) and partial heald-B (5) - of which at least one partial heald is engaged after each shedding motion. This allows production of the doup fabric (F) via an instantaneous lateral relative counter-displacement of the partial healds (4, 5) for the reciprocal displacement of the doup thread (17) which extends lengthwise to the ground warp thread (16).
• the warp threads of one of the pair of partial healds (4, 5) are guided freely by thread guide means (4C) to bring about the shedding, and, on the other partial heald, to bring about a side change.
• thread guide means (4C) to bring about the shedding, and, on the other partial heald, to bring about a side change.
• one key problem faced by the existing devices is that at high operating speeds and which involve complex movements of the threads, there is a lot of friction between the elements of the heald and the warp threads passing through.
• the lateral displacement system for doup end (17) of warp should also be reinforced to sustain high speed operation with minimal maintenance.
• the partial heald-A (4) is made in two components - a vertical movement facilitator (4B) and a lateral movement facilitator (4A).
• the components of the lateral movement facilitator (4 A) are preferably made of plastic material.
• the vertical movement facilitator (4B) is made of any material that is capable of withstanding jerks, vibrations, and shocks, such as metals and/or plastic or their combination.
• Figures 2 and 3 show a schematic of the movement of the assembled heald belt assembly of the invention while making the doup fabric (F).
• the two partial healds (4, 5) are formed from slit belt strands of flexible material, whereby the partial healds are connected using a belt (2) in a continuous belt form.
• a pair of pulleys (1) supports the continuous belt holding the pair of healds (4, 5).
• a relative lateral movement is imparted to the lateral movement facilitator (4A) which moved about a pivot (9).
• the relative lateral movement is imparted using a first cam/follower arrangement which allows the lateral movement facilitator (4A) to rotate in its own plane.
• the first cam/follower assembly comprises a first follower (6A) and a first cam (6B) that ultimately facilitate the rocking movement of the lateral movement facilitator (4A) in its own plane.
• a shedding movement is imparted to partial heald-A (4) through a second cam/follower assembly (also termed as shedding cam assembly) that allows upward/downward movement of the vertical movement facilitator (4B).
• the second cam/follower assembly comprises a second follower or a shedding cam follower or roller (7 A) and a second cam or a shedding cam (7B).
• doup fabric (F) is a result of one warp thread jumping onto the other side of the other warp thread caused by the preliminary tension developed in the warp threads produced by the pair of partial healds (4, 5).
• the pair of partial heads engages with each other in a comb-like arrangement of guide means (4C) provide on at least one of the partial healds (4, 5).
• the guide means have a thread eye (3) at their free ends through which threads (16, 17) pass for shedding and also thread guide slits between the consecutive guides which are used for bringing about the side change.
• the eye (3) is provided with a replaceable insert (3 A), made preferably of ceramic material or of metallic material provided with coating or lamination of suitable wear resistance.
• the partial healds (4, 5) can be made from slit belt strands, wherein for approximately each partial heald (4, 5), an endless flexible belt (2) extends over each of the rotating supported guide rollers (1) on the upper respectively lower frame sections.
• the inner partial heald-A (4) and the outer partial heald-B (5) of the belt (2) assembly each carry a thread eye (3) provided with a replaceable insert (3 A) through each of which a warp thread of one or the other warp-thread sheets is drawn.
• the generation of an oppositely phased up-and-down reciprocating motion of the strands of the belt (2) permits the change-of-shed motion on the two warp-thread sheets to take place.
• the inner strand is fastened tightly with heald slide or shed cam lever (15), the shed cam lever (15) being slid vertically up and down on guide means.
• warp threads of one partial heald of the partial heald pair (4, 5) are in each case guided freely by thread guide means (4C) to bring about the shedding and, on the other partial heald, to bring about a side change, as is subsequently explained.
• the partial healds (4, 5) support comb like guide means (4C) for the warp threads, the teeth or prongs (8) of the guide means (4C) each having a thread eye disposed on the free end thereof for the shedding guidance of a warp thread, and, defining between each tooth (8) and the next, thread guide slits for the freely guided warp threads for bring about the side change.
• the development is such that the partial healds of the partial heald pair (4, 5) support comb-like guide means (4C) arranged opposite to each other, which are mounted on heald belt (2).
• the doup thread (17) lies first to the left of the ground thread (16).
• the warp threads receive a preliminary tensioning that causes the warp threads, at the next zero-passage, to change sides by jumping over, which illustrates the completed change of motion.
• the doup thread (17) lies to the right of the ground thread (16).
• the comb-like guide means (4C) of the inner partial heald-A (4) can regain its other (left) extreme position under the effect of the torsion spring (13), which again leads to a change of side of the warp threads, and so forth.
• Said swivelling of said rocking lever (10) takes place by way of swing control cams (6B) mounted on the plate of the loom.
• the swing control cam (6B) pushes the swing control cam roller (6A) against the torsion spring (13) mounted with swivel bush (12) resulting in the swinging motion of swivel arm (11).
• the swivel arm (11) has striker arm, which imparts the lateral displacement to heald comb through rocking lever (10).
• swivel bush (12) undergoes tremendous strain for cycle of motion, it has higher wear tendency.
• swivel bush (12) was developed from wear resistance material preferably metallic alloy.
• the conventional looms use a rubber bush type element for giving swing motion to comb bar.
• the metallic swivel bush (12) introduced in this invention has a spring base system (13) for shock/impact resistance. It has been found that this has led to reduction in maintenance/replacement time and expenditure. From the above described device and method, the developed inventive circular loom can produce doup tubular fabric of consistent quality at about 15 to 40% higher production rate compared to conventional method. It was also found that with the usage of replaceable ceramic insert (3 A) and /or metallic low wear swivel bush (12) of the invention the service life of components and inventive circular loom have increased by 10 to 18 times over conventional parts and circular loom.
• a centralised main drive (not shown in figures) for both cams (6B and 7B)
• a take-up drive (not shown in figures) for fabric haul-off
• a warp let off drive (not shown in figures)
• a fabric winder drive (not shown in figures)
• the invention also discloses a method of manufacturing a doup fabric (F) using a circular loom fitted with the partial heald assembly. It comprises the steps of providing a loom fitted with the partial heald assembly as described here.
• a method for manufacturing a doup weave tubular fabric (F) in a circular loom wherein both ground warp (16) and doup warp ends (17) are subjected to a positive shedding motion, further the doup warp end (17) lateral displacement on one side of said ground warp (16) is achieved by a swing control cam (6B), and at a next shedding, said doup warp end (17) is shifted on the opposite side of said ground warp end (16) to form a shed after said doup warp (17) passes beneath said ground warp end (16), and the shedding motion of said doup warp ends (1) is repeated.
• doup fabric (F) is formed where one warp thread jumps onto the other side of the other warp thread caused by the preliminary tension developed in the warp threads produced by the pair of partial healds (4, 5).
• the pair of partial heals (4, 5) engages with each other in a comb-like arrangement of guide means (4C) provide on each of the partial healds (4, 5), wherein the guide means (4C) have a thread eye (3) at their free ends through which threads pass for shedding and also thread guide slits between the consecutive guides which are used for bringing about the side change.
• the eye (3) is provided with a ceramic insert (3 A) to reduce friction.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Looms (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=76128764

Family Applications (1)

Country Status (3)

Families Citing this family (1)

Family Cites Families (10)

• 2020
  • 2020-11-23 WO PCT/IB2020/061027 patent/WO2021105847A1/en unknown
  • 2020-11-23 CN CN202080082360.4A patent/CN114787436B/zh active Active
  • 2020-11-23 EP EP20894754.9A patent/EP4065758A4/de active Pending

Also Published As

Similar Documents

Legal Events