US475625A

US475625A - Island

Info

Publication number: US475625A
Authority: US
Publication date: 1892-05-24
Anticipated expiration: 1909-05-24

Description

(No Model.) 2 Sheets-Sheet 1. I

G. W. STAFFORD. SHEDDING MECHANISM FOR L-OOMS.

No. 475,625. Patented May 24, 1892.

(No Model.) 2 SheetsSheet 2.

G. W. STAFFORD. SHEDDING MECHANISM FOR LOOMS.

No. 475,625. Patented May 24, 1892.

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UNITED STATES PATENT OFFICE.

GEORGE W. STAFFORD, OF PROVIDENCE, RHODE ISLAND.

-SHEDD|NG MECHANISM FOR LOOMS.

SPECIFICATION forming part of Letters Patent No. 475,625, dated May 24, 1892.

Application filed November 16, 1891- Serial No. 412,083. (No model.)

To all whom it may concern.-

Be it known that I, GEORGE W. STAFFORD, a citizen of the United States, residing at Providence, in the county of Providence and State of Rhode Island, have invented certain new and useful Improvements in Shedding Mechanism for Looms, of which the following is a specification, reference beinghad therein to the accompanying drawings.

My invention relates to double-action dobbies or shedding mechanisms for looms. These have heretofore generally comprised a connector or jack-lever which is pivotally mounted at mid-length thereof upon each harness-operating lever, hooked jacks which are pivoted to the upper and lower ends, respectively, of each connector or jack-lever, and are controlled in their position by means of patternindicators applied to the surface of a patterndrum or to a chain which passes around a suitable cylinder or drum, the said indicators acting to determine the position of the jacks through intermediately-placed pattern or indicator levers, and wires or needles resting upon the said pattern or indicator levers and supporting the free ends of the hooked jacks. Usually the lower jack of the pair of jacks which are pivoted to the opposite ends of a connector or jack-lever rests upon the upturned inner end of one pattern or indicator lever, while the upper jack of the said pair is supported by a vertical wire or needle which at its lower end rests upon the inner end of an adjacent pattern or indicator lever. The hooked jacks, when permitted to descend by the pattern-controlling devices aforesaid, are engaged by reciprocating draw-bars, which are called lifters. One lifter is placed beneath the upper series of hooked jacks in the dobby or shedding mechanism in position to engage therewith when required, and the other lifter is placed beneath the lower series of hooked jacks in position to engage therewith when required. The lifters are reciprocated in parallel horizontal planes, and they move in a given direction alternately, they being actuated by devices connected with the driving mechanism of the loom,whereby one of them is moved outward prior to one pick of the loom and the other is moved outward prior to the next pick of the loom, and so on successively.

The object of my invention is to provide a double-action dobby of improved and simplified construction and at the same time to provide a dobby that shall retain all of the advantages that are found to be possessed by known dobbies of this class.

My invention consists of certain novel and improved combinations and arrangements of parts, which will now be described with reference to the accompanying drawings, and which will be particular pointedout and defined in the claims at the close of this specification.

Figure 1 of the drawings is a view in side elevation of a dobby embodying my present i11- vention. Fig. 2 is a-view of the said dobby in end elevation, the same being viewed from the right-hand side in Fig. 1, the upper portions of the harness-levers being broken away in the said Fig. 2 and thehooked jacks or hooks and certain adjacent parts being omitted. Fig. 3 is a view showing the dobby as it would appear in longitudinal section, parts of the side frame being broken away. Fig. e is a View in plan of the side frames and certain parts, which will hereinafter be referred to. Fig. 5 is a detail view showing a section on line 00 0c in Fig. 3.

In the drawings, a a are the side frames of the dobby, and b is a rod or shaft fixed in downwardly-projecting extensions of the said side frames, this shaft serving as the pivotal support or fulcrum for the harness-operating levers c. The upper ends of the levers project up through and are guided in the slots of an over arching curved grate d, which is fastened by bolts e to the side frames or a. When in their innermost position, the inner edges of the said upper ends of the harness-levers 0 rest against the outer face of a back-stop bar f, which is secured by bolts 9 to the said side frames a a.

Each harness-lever c has on one side thereof two headed studs h h, the stud 72' being nearer the center or fulcrum on which the harness-levers 0 turn than the stud h, the head of this stud h being removed in Fig. 3 in order to show the mannerin which the hooked jacks or hooks z' z" are fitted to the stems of the studs h h. The jacks or hooks c e" have slotted or looped body portions, as shown in Fig. 3, which fit upon the studs, their outer ends 71 being hooked. The outer portion of the body of each jack or book is expanded or increased in vertical width at 41 this expanded or widened portion being connected by an incline t with the narrower portion of the jack or hook, and the object of this feature of oonthe lifters or draw-bars 0 0, are determined by the indicators Z, which are applied to bars 1, passing around a grooved drum on cylinder P, the indicators acting against the under side of the outer ends of the pattern or indicator levers m m, which are mounted side by side upon a cross-rod m supported in the side frames at a. The inner end of the pattern or indicator lever m supports a vertical wire or needle it, upon the upper end of which rests the upper jack '1', while the lower jack 2" rests directly upon the inner end of the patternlever m. The jacks, when their hooked ends are permitted to remain in their depressed position, as in the case of the jack '5 in Fig. 3, are engaged by lifters or draw-bars 0 0' and moved outward thereby. These lifters or draw-bars have connected therewith jack-returning bars 11 p, which serve, respectively, asv a lifter or draw-bar moves inwardly to force inwardly, also, any jack or book which may have been carried outward by the corresponding lifter or draw-bar in the outward movement thereof and which may not have been returned to the normal position (represented in Fig. 3) in consequence of the movement of a harness-lever inward.

The ends of the lifters or draw-bars and connected returning-bars slidein slots a 0, formed in the side frames a a. Each end of each lifter or draw-bar is pivotally connected with one end of a connectingrod q. The other ends of the rods q pertaining to the upper lifter or draw-bar are connected to upwardlyextending arms 0* on opposite ends of a rockshaft .9, which is journaled in bearings in the side frames. a a, and the other ends of the rods q pertaining to the lower lifter or draw-' bar are connected to downwardly-extending l arms 1" on the said shaft s. The shaft 8 is provided at one end with an arm .9, which in practiceis connected by a rod to some suitable moving part of the loom, to which the dobby is applied, the said rock-shafts being in practice operated with such relative timing as that one lifter or draw-bar shall be caused to move outwardly at one pick of the loom and the other lifter or draw-bar shall be caused to move outwardly at the next pick of the loom, and so on successively.

For the purpose of impartinga step-by-step l movement of rotation to the drum orcylinder Z the shaft 1 of the said drum or cylinder is provided with a ratchet-wheel t, the teeth of which are engaged by a pawl u, pivoted to one of the arms 1*. The drum or cylinder is prevented from overrunning by means of a cheek-wheel 1), which is fast to the shaft Z in succession by the curved end of the holding-arm w, the said arm being pivoted to the side frame a and acted upon by a spring w. With the object in view of imparting more movement progressively to the rear harnesslevers in the loom I communicatemore movement to the rear ends of the lifters or drawbars than to the forward ends thereof. I effect this by connecting the rods q to the arms 0' r on one side of the dobby at points which are proportionately farther from the axis of the shaft 8 than arethe points at which the rods g on the other side of the dobby are connected with the corresponding arms '1' r at that side. For the purpose of avoiding lost motion when the harness-levers and lifters or draw-bars are thus operated the back-stop bar f is secured to the side frames a a in an inclined position, which is parallel with the i position occupied by the lifters or draw-bars 1 when in their innermost position. In order to prevent the hooks or jacks from moving too far inward and so insuring that they shall be indicated when required, a cross-wire i is passed through the open portions of the hooks I or jacks of each series, these wires being mounted in lugs projecting from the ends of the grates 7c. These cross-wires i extend from one side frame to the other in an inclined or angular position, as indicated in Fig. 5, they being parallel with the outer face of the back-stop barf. Inasmuch as the jacks t" engage with the studs h, which, are located nearer the center A or fulcrum on which the harness-levers turn *than are the studs 71, with, which the jacks i engage, it is necessary to provide for moving the upper lifter or draw-bar through a greater *path of movement than that through which I the lower lifter or draw-bar is moved. I therefore connect the rods q pertaining to the said upper lifter or draw-bar to the arms 'rat l points which are proportionately farther from the axis of the shaft 3 than are the points at j which the rods qpertaining to thelower lifter 4 or draw-bar are connected to the arms '1".

The grates k 10 preferably are cast in one land from the front side of the casting pro- ;jects a series of lugs 10*, the spaces between these lugs forming pockets for the reception of the upper ends of the needles n, the latter being retained in place bya cross-wire n, pass- 5 ing outsidevthe same and supported in lugs n pro ecting from the ends of the casting.

Having described my invention and the with which I am 1. The combination, with the harness-levers,

and is formed with recesses, which are entered" i best manner of reducing the same to practice movement at the rear ends thereof than at the forward ends thereof, and pattern-controlling devices for determining the engagement of the hooks or jacks with the lifters or draw-bars, substantially as described.

2. The combinatiomwiththeharness-levers, each having studs h h, and the upper and lower hooks or jacks having loose or sliding connection with the studs, of the lifters or draw-bars, the returning-bars moving with the lifters or draw-bars, the rock-shaft having arms 0" r at opposite ends thereof, the rods connecting the lifters or draw-bars with the said arms, the said rods at one side of the dobby being connectedwith the said arms at points which are proportionately farther from the axis of the shaft than are the points of connection at the other side and those pertaining to the upper lifter or draw-bar being connected with the upper arms at points which are proportionately farther from the said axis than are the points of connection between the lower lifter or draw-bar and the lower arms, the inclined back-stop bar, and pattern-controlling devices determining the engagement of the hooks with the lifters or draw-bars, substantially as described.

3. The combination, with the inclined backstop barf, the harness-levers, the studs 72. h thereon, and the hooks or jacks i 2", having loose or sliding connection with said studs, of the an gularlyplaced cross-wires t i", acting to determine the position of the hooks or jacks, the lifters or draw-bars, and means for operating the said lifters or draw-bars with a greater range of movement at the rear ends thereof than at the forward ends thereof, substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

GEO. W. STAFFORD.

Witnesses:

CHAS. F. RANDALL, WM. A. MACLEOD.