US3734142A - Shuttleless loom - Google Patents
Shuttleless loom Download PDFInfo
- Publication number
- US3734142A US3734142A US3734142DA US3734142A US 3734142 A US3734142 A US 3734142A US 3734142D A US3734142D A US 3734142DA US 3734142 A US3734142 A US 3734142A
- Authority
- US
- United States
- Prior art keywords
- casing
- batten
- secured
- frame
- shaft
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Classifications
-
- D—TEXTILES; PAPER
- D03—WEAVING
- D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
- D03D47/00—Looms in which bulk supply of weft does not pass through shed, e.g. shuttleless looms, gripper shuttle looms, dummy shuttle looms
-
- D—TEXTILES; PAPER
- D03—WEAVING
- D03D—WOVEN FABRICS; METHODS OF WEAVING; LOOMS
- D03D47/00—Looms in which bulk supply of weft does not pass through shed, e.g. shuttleless looms, gripper shuttle looms, dummy shuttle looms
- D03D47/27—Drive or guide mechanisms for weft inserting
- D03D47/275—Drive mechanisms
Definitions
- the invention relates to weaving looms with weft supply by large spools located outside the shed, said looms being provided with. at least one weft inserter at the extremity of a tape to which a reciprocating movement is imparted by a mechanism terminating in a toothed wheel which meshes with perforations of said tape.
- the invention is more especially directed to looms in which the alternating movement of rotation of the tape-driving wheel results from amplification of the oscillating movement of a toothed sector in meshing relation with a pinion which forms a two-stage gear system in conjunction with said wheel, said sector being carried by a lever which is usually extended beyond its pivotal axis by an arm which carries a single or double roller, said roller being controlled with very high precision by the groove of a cam which carries out a uniform movement of rotation within a closed casing containing oil in which the cam is immersed.
- the tape moves within guides which are rigidly fixed to the slay and the mechanism for actuating the tape from the cam which is disposed within the closed casing takes part in the oscillating motion of the batten about the driving shaft of the cam by means of a frame comprising inclined legs which are fixed at the lower ends thereof on the top of the casing.
- the object of this invention is to endow said oscillat ing assembly with the maximum degree of rigidity.
- the weaving loom in accordance with the invention is characterized in that the complete assembly which comprises the body of the cam casing, the connection between the casing and the batten, the bearing which supports the pivotal shaft of the lever which carries the toothed sector as well as its connection with said casing and with the batten is constructed in the form of a'one-piece unit, that is to say a single part.
- the batten 1 oscillates about a horizontal shaft2 which is carried by the frame 3 of the loom.
- the tape 4 the front end of which is not visible in the drawing, carries the weft inserter and is endowed with a reciprocating movement by a toothed wheel 5 which meshes with perforations of the tape and forms together with a pinion 6 an assembly which is freely mounted on a shaft 7 and actuated by an oscillating toothed sector 8 carried by a lever 13 which comprises a hub 13b pivotally mounted on a stub shaft 18 located at right angles to the shaft 2 and secured in a bearing 19.
- Said tape is guided within the shed by a succession of small guides 9 outside the shed, said tape is first transferred within a rectilineal slideway 10, then within an arch 11 by which it is guided and returned to a point beneath the slay at which said tape is received in a conduit 12.
- the lever 13 carries out in known manner an oscillat ing movement which is obtained from a cam 14 having a groove 15 of approximately sinusoidal shape in which is engaged a cam-following roller 16, said roller being mounted for free rotational motion at the end of a lower arm 13a which forms an extension of the lever 13.
- the cam 14 is keyed on the shaft 2 which is driven in continuous rotational motion by means which are not illustrated.
- the cam 14 which is immersed in oil and the arm 13a move within the interior of a sealed casing 17 which is freely mounted. for pivotal motion on the shaft 2.
- the casing 17 has upward extensions in the form of lateral upright members 20 located on each side of a flat web 21 provided with stiffening end-ribs 22.
- the web 21 and the ribs of this latter are joined to an upper return portion forming a flange 23 which carries the rectilineal slideway 10 of the tape 4 and beneath which is fixed the batten 1.
- the casing 17 is provided on the front face thereof with an opening 25 which is closed by a cover 26 (which is assumed to have been removed in FIG. 1) and the lower portion 27 of the casing has a raised portion in order to contain the lubricant when the cover is removed for the purpose of inspecting the components which are located within the casing
- the rear face of the casing is provided with a wide opening 28 which provides ready access to the interior and which is closed by a cover 29.
- the cam is inserted through said rear opening 28.
- the distance between the front and rear faces of the casing 17 which is constituted by the lower portion of the single part is substantially reduced with respect to the corresponding size of the casing in the arrangement which was adopted in the prior art this reduction in size has the advantage of facilitating moulding and machining of this unit. It will be understood that the principle of the single part is applicable to a casing which is open only on the front side.
- Ribs 30 located inside the casing as well as the corresponding portion of the ribs 22 and also the ribs 24 pro- 1 vide the top portion of said casing with a very high degree of rigidity between the bearings of the shaft 2 and the bearing 19 this has the effect of preventing deformations under the action of the axial components of forces between the groove of the cam 14 and the roller 16 of the arm 13a of the lever 13 invariability of the precise axial position of the cam with respect to the stub shaft 18 of the lever 13 is accordingly ensured.
- the assembly which is formed by the casing 17, the bearing 19, the lateral upright members 20 and the rigid web 21 which is suitably ribbed and on which the slay is fixed constitutes a single one-piece part.
- the upper portion of the single part comprises lateral extensions 22a, with the result that said single part is secured over a substantial distance to the batten l which is extended for this purpose and also in order to receive the arch 9 at the end of said batten.
- the extension of the batten 1 up to the arch 11 has the important advantage of eliminating the articulation effect which, in the known arrangement adopted in the prior art, resulted in the short attachment of the oscillating frame to the end of the batten, the length of which was of substantially smaller value.
- the elements for transmitting the movement of the toothed sector 8 to the tape 4 are supported on the one hand by the web 21 and on the other hand by a bearing 31 which is secured to the batten 1.
- connections are provided by means of uninterrupted walls which are oriented in the most favorable direction for transmission of forces and which can have substantial dimensions. This also makes it possible to dispense with any need for the machining operations which would otherwise be necessary for the difficult assembly of the separate casing and frame.
- the cam casing 17 which was previously provided with an opening only on its front face 25 and closed by a cover 26 can also have an opening on the rear side 28 and is closed in this case by a cover 29, t
- this arrangement facilitates positioning of the cam 14 which is of substantial mass by virtue of the fact that the rear opening 28 is larger than the front opening 25 owing to the raised bottom edge 27 of said front opening 25.
- this concept makes it possible to obtain from a single casting pattern either a part for the right-hand portion of the loom or a part from the left-hand portion.
- the rectilineal slideway 10 is secured by means of an intermediate member.
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- Engineering & Computer Science (AREA)
- Textile Engineering (AREA)
- Looms (AREA)
Abstract
The complete assembly which comprises the body of the cam casing, the connection between the casing and the batten, the bearing which supports the pivotal shaft of the lever which carries the toothed sector as well as its connection with said casing and with the batten is constructed in the form of a onepiece unit, that is to say a single part.
Description
United States Patent [191 1 3,734,142
Dewas {4 1 May 22, 1973 [54] SHUTTLELESS LOOM 1,747,098 2 1930 Ambler ..139 127 R [76] Inventor: Raymond Dewas, 120 Boulevard de Saint Quentin 80 Amiens, France FOREIGN PATENTS OR APPLICATIONS [22] Filed: July 15, 1971 657,917 3/1938 Germany ..139/123 [21] Appl' 162916 Primary Examiner-Henry S. Jaudon Att0rney-V. Alexander Scher et Eli. [30] Foreign Application Priority Data July 21, 1970 Luxembourg ..61379 [57] ABSTRACT The complete assembly which comprises the body of [52] US. Cl ..l39/l23 the cam casing the connection between the casing [5 ll!- CI. and the bane, h i g pp the pivotal Fleld of Search R, 123, 127, Shaft of the level, which carries the toothed Sector as 139/188 190 well as its connection with said casing and with the batten is constructed in the form of a one-piece unit, [56] References C'ted that is to say a single part.
UNITED STATES PATENTS 6 Claims, 3 Drawing Figures 3,232,321 2/1966 Dewas ..l39/l23 SHUTTLELESS LOOM The invention relates to weaving looms with weft supply by large spools located outside the shed, said looms being provided with. at least one weft inserter at the extremity of a tape to which a reciprocating movement is imparted by a mechanism terminating in a toothed wheel which meshes with perforations of said tape. The invention is more especially directed to looms in which the alternating movement of rotation of the tape-driving wheel results from amplification of the oscillating movement of a toothed sector in meshing relation with a pinion which forms a two-stage gear system in conjunction with said wheel, said sector being carried by a lever which is usually extended beyond its pivotal axis by an arm which carries a single or double roller, said roller being controlled with very high precision by the groove of a cam which carries out a uniform movement of rotation within a closed casing containing oil in which the cam is immersed.
An arrangement of this type is described in the applicants U.S. Pat. No. 3,232,321.
In looms of this type, the tape moves within guides which are rigidly fixed to the slay and the mechanism for actuating the tape from the cam which is disposed within the closed casing takes part in the oscillating motion of the batten about the driving shaft of the cam by means of a frame comprising inclined legs which are fixed at the lower ends thereof on the top of the casing.
of the grooved cam whilst the upper portion which is attached to one end of the batten over a short distance receives the support of the toothed wheel which drives the tape.
The law of oscillating motion of the lever which carries the toothed sector is the resultant of the uniform movement of rotation of the cam groove and of the forward and backward movements of the slay with respect to the fell of the cloth. The interactions of these two movements are disturbed by the effects of elasticity of the complete assembly which oscillates with the slay and these disturbances are greater as the looms operate at progressively higher speeds and/or in respect of progressively greater widths of cloth this results in rebounding of the cam-following roller which, although infinitesimal, gives rise .to high stresses between the roller and the cam and throughout the tape actuating assembly.
It is therefore necessary to ensure that said oscillating assembly has a very high degree of rigidity relatively to the different directions of forces. In point of fact, the
known arrangement consisting of a casing and a separate frame which are assembled together cannot ensure such a degree of rigidity.
The object of this invention is to endow said oscillat ing assembly with the maximum degree of rigidity.
To this end, the weaving loom in accordance with the invention is characterized in that the complete assembly which comprises the body of the cam casing, the connection between the casing and the batten, the bearing which supports the pivotal shaft of the lever which carries the toothed sector as well as its connection with said casing and with the batten is constructed in the form of a'one-piece unit, that is to say a single part.
The characteristic features and advantages of the invention will be more readily understood from the following description and from a study of the accompanying drawings in which one embodiment of the invention is shown by way of example without any limitation being implied, and in which FIG. 1 is a front view in elevation showing the righthand side of a weaving loom for the application of the invention as seen by an observer who is stationed in front of the loom FIG. 2 is a vertical sectional view taken along line II-II in FIG. 1, the frame having been omitted for the sake of clarity I FIG. 3 is a partial horizontal sectional view taken along line III-11] of FIG. 1.
The batten 1 oscillates about a horizontal shaft2 which is carried by the frame 3 of the loom. The tape 4, the front end of which is not visible in the drawing, carries the weft inserter and is endowed with a reciprocating movement by a toothed wheel 5 which meshes with perforations of the tape and forms together with a pinion 6 an assembly which is freely mounted on a shaft 7 and actuated by an oscillating toothed sector 8 carried by a lever 13 which comprises a hub 13b pivotally mounted on a stub shaft 18 located at right angles to the shaft 2 and secured in a bearing 19. Said tape is guided within the shed by a succession of small guides 9 outside the shed, said tape is first transferred within a rectilineal slideway 10, then within an arch 11 by which it is guided and returned to a point beneath the slay at which said tape is received in a conduit 12.
The lever 13 carries out in known manner an oscillat ing movement which is obtained from a cam 14 having a groove 15 of approximately sinusoidal shape in which is engaged a cam-following roller 16, said roller being mounted for free rotational motion at the end of a lower arm 13a which forms an extension of the lever 13. The cam 14 is keyed on the shaft 2 which is driven in continuous rotational motion by means which are not illustrated. The cam 14 which is immersed in oil and the arm 13a move within the interior of a sealed casing 17 which is freely mounted. for pivotal motion on the shaft 2.
The casing 17 has upward extensions in the form of lateral upright members 20 located on each side of a flat web 21 provided with stiffening end-ribs 22. The web 21 and the ribs of this latter are joined to an upper return portion forming a flange 23 which carries the rectilineal slideway 10 of the tape 4 and beneath which is fixed the batten 1.
The casing 17 is provided on the front face thereof with an opening 25 which is closed by a cover 26 (which is assumed to have been removed in FIG. 1) and the lower portion 27 of the casing has a raised portion in order to contain the lubricant when the cover is removed for the purpose of inspecting the components which are located within the casing the rear face of the casing is provided with a wide opening 28 which provides ready access to the interior and which is closed by a cover 29. In this arrangement, the cam is inserted through said rear opening 28.
In the same case, the distance between the front and rear faces of the casing 17 which is constituted by the lower portion of the single part is substantially reduced with respect to the corresponding size of the casing in the arrangement which was adopted in the prior art this reduction in size has the advantage of facilitating moulding and machining of this unit. It will be understood that the principle of the single part is applicable to a casing which is open only on the front side.
The assembly which is formed by the casing 17, the bearing 19, the lateral upright members 20 and the rigid web 21 which is suitably ribbed and on which the slay is fixed constitutes a single one-piece part.
The upper portion of the single part comprises lateral extensions 22a, with the result that said single part is secured over a substantial distance to the batten l which is extended for this purpose and also in order to receive the arch 9 at the end of said batten.
The extension of the batten 1 up to the arch 11 has the important advantage of eliminating the articulation effect which, in the known arrangement adopted in the prior art, resulted in the short attachment of the oscillating frame to the end of the batten, the length of which was of substantially smaller value.
The elements for transmitting the movement of the toothed sector 8 to the tape 4 are supported on the one hand by the web 21 and on the other hand by a bearing 31 which is secured to the batten 1.
By virtue of the design concept of the one-piece part, the connections are provided by means of uninterrupted walls which are oriented in the most favorable direction for transmission of forces and which can have substantial dimensions. This also makes it possible to dispense with any need for the machining operations which would otherwise be necessary for the difficult assembly of the separate casing and frame.
In order to facilitate manufacture of this large component, the cam casing 17 which was previously provided with an opening only on its front face 25 and closed by a cover 26 can also have an opening on the rear side 28 and is closed in this case by a cover 29, t
with the result that the internal shape of said casing can be obtained by means of a simple moulding operation moreover, this arrangement facilitates positioning of the cam 14 which is of substantial mass by virtue of the fact that the rear opening 28 is larger than the front opening 25 owing to the raised bottom edge 27 of said front opening 25.
The single one-piece part permits construction of strong uninterrupted external ribs 22 which cooperate with the internal ribs 30 of the casing in order to ensure rigidity in the direction of axial thrust resulting from the composition of forces between the groove 15 of the cam and the roller 16 of the lever 13.
It should be pointed out that the design concept of the single-piece part which provides a connection between the batten 1 and the casing 17 to which an oscillating movement is imparted by said batten makes it possible to contemplate the elimination of the corresponding conventional sword of the batten which is consequently carried by the shaft 2 solely by means of the one-piece part.
Finally, this concept makes it possible to obtain from a single casting pattern either a part for the right-hand portion of the loom or a part from the left-hand portion.
As is wholly apparent, it would be possible to make modifications and additions as well as to contemplate the use of equivalent means without thereby departing from the spirit of the invention.
From this it follows that, in order to endow the bearing 19 with the necessary degree of rigidity, the web 21 could be stiffened by means of corrugations instead of making use of ribs 24. The central portion of the web 21 could also be provided with an opening whose contour is strengthened by means of ribs.
Instead of having a return portion 23 beneath which the slay is fixed, it would also be possible to bring the top portion of the one-piece part beneath the sectional member which constitutes the batten 1 in this case, the rectilineal slideway 10 is secured by means of an intermediate member.
What I claim is 1. In a shuttleless loom with a reciprocating weft inserter carrying tape having regularly spaced perforations, a single member having separate sections and comprising a loom frame and a casing, a horizontal shaft carried by said loom frame, said casing being pivotally mounted on said horizontal shaft and carrying an upwardly extending frame, a cam secured to said hori zontal shaft within said casing, a bearing carried by said casing and directed at right angles to said horizontal shaft, a stub shaft secured in said bearing, a lever mounted for oscillating movement on said stub shaft, a cam follower carried by said lever and engaged with said cam, a toothed sector connected to said lever, a toothed pinion meshing with said toothed sector, a toothed wheel secured to said toothed pinion and meshing with said perforations of said tape, a further shaft carrying said toothed wheel and pinion, a frame extending upwardly from said casing, a batten secured to the top of said upwardly extending frame, and two further bearings respectively carried by said batten and by the upper portion of said upwardly extending frame for supporting said further shaft, said casing, bearing, and frame being formed as a single one-piece part.
2. A loom as defined in claim 1, wherein said upwardly extending frame is formed by web connected ribs.
3. A combination as defined in claim 1, wherein the upper portion of said one-piece part is formed with a rectilinear horizontal flange, said batten being secured to the lower face of said flange.
4. A combination as defined in claim 3, further comprising a guide secured to the upper face of said flange for guiding said tape.
5. A combination according to claim 1, wherein the upper portion of said upwardly extending frame is formed with lateral extensions to which said batten is also secured.
6. A combination as defined in claim 1, further comprising a lateral curved guide extending downwardly to guide said tape laterally and downwardly under said batten, said batten extending to the upper portion of said guide.
Claims (6)
1. In a shuttleless loom with a reciprocating weft inserter carrying tape having regularly spaced perforations, a single member having separate sections and comprising a loom frame and a casing, a horizontal shaft carried by said loom frame, said casing being pivotally mounted on said horizontal shaft and carrying an upwardly extending frame, a cam secured to said horizontal shaft within said casing, a bearing carried by said casing and directed at right angles to said horizontal shaft, a stub shaft secured in said bearing, a lever mounted for oscillating movement on said stub shaft, a cam follower carried by said lever and engaged with said cam, a toothed sector connected to said lever, a toothed pinion meshing with said toothed sector, a toothed wheel secured to said toothed pinion and meshing with said perforations of said tape, a further shaft carrying said toothed wheel and pinion, a frame extending upwardly from said casing, a batten secured to the top of said upwardly extending frame, and two further bearings respectively carried by said batten and by the upper portion of said upwardly extending frame for supporting said further shaft, said casing, bearing, and frame being formed as a single one-piece part.
2. A loom as defined in claim 1, wherein said upwardly extending frame is formed by web connected ribs.
3. A combination as defined in claim 1, wherein the upper portion of said one-piece part is formed with a rectilinear horizontal flange, said batten being secured to the lower face of said flange.
4. A combination as defined in claim 3, further comprising a guide secured to the upper face of said flange for guiding said tape.
5. A combination according to claim 1, wherein the upper portion of said upwardly extending frame is formed with lateral extensions to which said batten is also secured.
6. A combination as defined in claim 1, further comprising a lateral curved guide extending downwardly to guide said tape laterally and downwardly under said batten, said batten extending to the upper portion of said guide.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
LU61379 | 1970-07-21 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3734142A true US3734142A (en) | 1973-05-22 |
Family
ID=19726427
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US3734142D Expired - Lifetime US3734142A (en) | 1970-07-21 | 1971-07-15 | Shuttleless loom |
Country Status (8)
Country | Link |
---|---|
US (1) | US3734142A (en) |
BE (1) | BE770243A (en) |
CA (1) | CA945871A (en) |
CH (1) | CH542301A (en) |
ES (1) | ES394107A1 (en) |
FR (1) | FR2099494B1 (en) |
GB (1) | GB1322675A (en) |
LU (1) | LU61379A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3951178A (en) * | 1974-12-13 | 1976-04-20 | Cox Foundry And Machine Co. | Shuttleless loom |
DE2637818A1 (en) * | 1975-09-19 | 1977-03-24 | Picanol Nv | IMPROVED WEB MACHINE LOADING |
US4111240A (en) * | 1977-01-03 | 1978-09-05 | Bob Mallard Enterprises, Inc. | Loom drive mechanism |
Families Citing this family (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
IT1204675B (en) * | 1987-06-03 | 1989-03-10 | Colombo Filippetti Srl | DEVICE FOR THE TRANSFORMATION OF A UNIFORM ROTARY MOTORCYCLE INTO AN ALTERNATIVE ROTARY MOTORCYCLE, PARTICULARLY SUITABLE FOR TEXTILE FRAMES |
DE4233636A1 (en) * | 1992-10-06 | 1994-04-07 | Sulzer Ag | Device for driving a rapier belt and rapier weaving machine with such a device |
EP0826807A1 (en) * | 1996-09-02 | 1998-03-04 | Cheng, Chuan-tien | Apparatus for driving a carriage of a shuttle in a weaving loom |
-
1970
- 1970-07-21 LU LU61379D patent/LU61379A1/xx unknown
-
1971
- 1971-07-15 US US3734142D patent/US3734142A/en not_active Expired - Lifetime
- 1971-07-16 GB GB3343071A patent/GB1322675A/en not_active Expired
- 1971-07-16 FR FR7126094A patent/FR2099494B1/fr not_active Expired
- 1971-07-20 ES ES394107A patent/ES394107A1/en not_active Expired
- 1971-07-20 BE BE770243A patent/BE770243A/xx not_active IP Right Cessation
- 1971-07-20 CA CA118,706A patent/CA945871A/en not_active Expired
- 1971-07-20 CH CH1066771A patent/CH542301A/en not_active IP Right Cessation
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3951178A (en) * | 1974-12-13 | 1976-04-20 | Cox Foundry And Machine Co. | Shuttleless loom |
DE2637818A1 (en) * | 1975-09-19 | 1977-03-24 | Picanol Nv | IMPROVED WEB MACHINE LOADING |
US4111240A (en) * | 1977-01-03 | 1978-09-05 | Bob Mallard Enterprises, Inc. | Loom drive mechanism |
Also Published As
Publication number | Publication date |
---|---|
BE770243A (en) | 1971-12-01 |
GB1322675A (en) | 1973-07-11 |
FR2099494B1 (en) | 1974-03-29 |
ES394107A1 (en) | 1976-01-01 |
LU61379A1 (en) | 1970-09-21 |
CA945871A (en) | 1974-04-23 |
FR2099494A1 (en) | 1972-03-17 |
CH542301A (en) | 1973-09-30 |
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