US2529694A - Picker stick linkage - Google Patents

Description

Nov. 14, E950 G. H. HUFFERD PICKER STICK LINKAGE 2 Sheets-Sheet l Filed July 27, 1948 Y /ad /361 ,Ivrenfr l 650265 H. Huf-F620 Nov. 14, i950 G. H. HUFFERD PICKER STICK LINKAGE Filed July 27, 1948 2 Sheets-Sheet 2 l?? y-Enbr 650265 /7C Huf/C590 Patented Novu 14, 1950 PICKER STICK LENKAGE George H. Huiferd, Shaker Heights, Ohio, assignor to Houdaille-Hershey Corporation, Detroit, Mich., a corporation of Michigan Application July 27, 1948, Serial No. 40,894

5 Claims.

This invention relates to an improved loom construction, and particularly to an improved linkage for controlling the movements of the picker stick of a ily shuttle type loom.

As is well known, the movement of the picker sticks of a loom is one of the most critical factors entering into the successful operation of the loom at high speed. In all loom constructions wherein a picker is rigidly secured to the top end of the picker stick, it is essential that the path of movement of the shuttle-engaging portions of the picker define a substantially straight line, generally parallel to the path of movement of the shuttle along the lay.

In my copending application Serial No. 37,951, filed July 9, 1948, there is described and claimed a unique control linkage for a picker stick embodying the supporting of the picker stick entirely from a primary bracket which is secured to the end of the rock shaft which is commonly found on all looms. The control linkage constituted a pair of links which had their opposite ends respectively secured to spaced pivot bearings provided on the primary bracket vand on a secondary bracket which is adapted for rigid securement to the lower portion of the picker stick. Specically, the construction of my above identied pending application involved a lower link of substantial length which was generally horizontally disposed and hence imparted primarily av lateral positioning control upon the picker stick throughout the normal range of movement of the stick. The other link was relatively short in length and was pivotally secured in depending relationship to a pivot bearing on the primary bracket which was substantially laterally displaced from the end of the rock shaft. While such an arrangement has been found to be very effective in controlling the movements of the picker stick `to provide the required straight line path for the shuttle engaging portions of the picker, some difficulties were presented in obtaining the necessary clearance for the various moving parts and particularly, in providing suicient space for the connection of a hydraulic check unit to operate between the primary and secondary brackets to check both the shuttle throwing and the shuttle catching movements of the picker stick. Furthermore, the essential geometry of the linkage involved symmetrical displacements of the short link on either side of its vertical position.

Accordingly, it is an object of this invention to provide an improved control linkage for the picker stick of a loom of the type employing a pair of links pivotally connecting a picker stick Still another object of this invention is the' provision of a double link support for a picker stick wherein both links pivot only through a very limited range to produce the requisite displacements of the picker stick and furthermore wherein neither link passes a vertical position,

The specific nature of the invention, as well as other objects and advantages thereof, will become apparent to those skilled in the art from the following detailed description of the annexed sheets of drawings, which, by way of preferred example only, illustrate two embodiments of the invention.

On the drawings:

Figure 1 is a side elevational View of a picker stick control linkage embodying this invention, showing the linkage in assembled relationship to the rock shaft and pickerstick of the loom.

Figure 2 is an end elevational view of the linkage of Fig.V 1 looking at such linkage from the rock shaft side thereof.

Figure 3 is a schematic View showing the various :positions assumed by the linkage elements and the picker stick throughout the normal range of movement of the picker stick.

Figure 4 is a view similar to Fig. 3 but illustrating the movements of the picker stick accomplished by a modied form of the invention wherein links of non-uniform length are employed.

As shown on the drawings:

Referring to Fig. l, the numeral I0 indicates a rock shaft of a loom, while the numeral il indicates a conventional picker stick. The picker stick Il is supported for oscillating movements with respect to the rock shaft l0, hence with respect to the lay of the loom (not shown), by a linkage constructed in accordance with this invention, which linkage controls the movement of the picker stick so that the shuttle-engaging portions of a picker (not shown) which is conventionally secured to the top end of the picker stick, traverses a substantially horizontal straight line path. In general, the linkage comprises a primary bracket I2, rigidly secured to the rock shaft I0, and a secondary bracket I3 which is secured to the lower portion of the picker stick II and connected to the primary bracket I2 by a pair of pivoted links I4 and I5. The links I4 and I5 may conveniently comprise either single or double links according to the nature of their pivotal support, but in the particular example illustrated in the drawings, such links are both double links, i. e., they each comprise a pair of identical parallel links for reasons that will be more fully apparent later.

The primary bracket I2 constitutes an integral casting having a split depending portion [2a dening a cylindrical recess to receive the end of rock shaft I0. The split portion I2a is clamped to the rock shaft III by a transverse bolt I2d and a transverse tapered key I1. The key I'I is of longitudinally tapering configuration and is drawn into snug engagement with the shaft I0 by a nut I8 threaded upon the threaded end portion of the key. As indicated in Fig. l, the surface of key I'l which contacts the shaft III is of i concave conguration to provide a pair of parallel biting edges Il@ to increase the securement of engagement of the primary bracket I2 with respect to the rock shaft I0.

In addition, primary bracket I2 delines a pair of vertically spaced pivot bearings I2b and I2c respectively. Both of such bearings are mounted in generally overlying relationship with respect to the end o the rock shaft IIJ and it should be particularly noted that the primary bracket I2 does not project laterally beyond the end of rock shaft II] to any appreciable extent. This arrangement greatly increases the clearance available for the various moving parts of the linkage.

The secondary bracket I3 may also conveniently comprise an integral casting, being of generally U-shape configuration, and has the base portion I3a rigidly secured to the front face of the picker stick II in any convenient manner. For example, a plurality of bolts I9 may be 'provided which pass through a clamping plate engaging the rear face of the picker stick II and project through suitable holes in the secondary bracket base ISa to clamp the picker stick II between such space and the clamping plate 20.

Each of the arm portions I3b and I3c of the U-shaped secondary bracket I3 are of substantial height and hence project laterally from the picker stick a substantial distance. At the outer end of each of the arm portions, and respectively adjacent the top and bottom parts thereof, a pair of bosses i3d and I3e are provided which respectively deiine vertically spaced pivot bearings I3f and I3g. As is best shown in Fig, 2, the lateral spacing of the arm portions I3b and I3c of the secondary bracket I3 is suicient to permit such arm portions to straddle the primary brackets I2 if necessary in one of the extreme positions of the picker stick I I.

With the described arrangement, the upper pair of links I4 are pivotally secured between the upper pivot bearings I2c and I3f while the lower pair of links I5 are pivotally secured between the lower pivot bearings I2b and I3g. The links I4 and I5 are each disposed outwardly of the primary and secondary brackets I2 and I3 and are secured thereto by suitable pivot pins I6.

With the described arrangement, and when the vertical spacing between the primary bracket pivot bearings I2b and I2c is different from the vertical spacing of the pivot bearings I3f and I3g of the secondary brackets, so that the upper links I5 and lower links I4 are non-parallel, it will be found by ordinary design layout procedure, that the dimensions of the links I4 and I5 together with the spacing between the various pivot bearings may be conveniently selected so as to insure that the picker stick II will move along a path such that the shuttle-engaging portion of the picker stick will traverse a substantially straight, horizontal line.

The embodiment shown 1n Figs. 1 and 2 of the drawings is particularly advantageous inasmuch as both the upper links I4 and the lower links I5 are of identical size and hence interchangeable components may be employed. Referring to the schematic diagram of Fig. 3, it is clearly apparent that with the described linkage, the shuttle-engaging portion of the picker stick II, represented by the end of the short line designated IIa, will follow along a substantially horizontal straight line path when an oscillating movement is imparted to the picker stick II in conventional fashion, such as by the usual power lug (not shown). In this schematic diagram, the solid lines represent the intermediate position of the picker stick II and the associated linkage, while the dotted lines and the dot dash lines represent the eXtreme positions assumed by the picker stick.

The principles of this invention are not limited to arrangement wherein identical links are employed for the upper and lower links I4 and I5. As is clearly illustrated by the schematic diagram of Fig. 4, unequal length links may also be employed and by a suitable selection of the spacing between the various pivot bearings, this type of linkage will also result in the shuttleengaging portions of the picker stick II moving in a substantially straight line path. In the arrangement of Fig. 4, the upper link I4 is shown as being of somewhat greater length than the lower link I5.

In both modications it should be noted that a relatively small range of pivotal movement of the links I4 and I5 is required to produce the full range of movement of picker stick II. Furthermore neither link I4 or I5 passes through a vertical position.

It should be particularly noted that due to the U-shaped configuration of the secondary bracket I3, and the location of the pivot bearings I3f and I3g in the ends of the arm portions of bracket I3, so that the picker stick II is .located at a substantially laterally displaced position with respect to the primary bracket I2, plus the fact that the primary bracket I2 does not project laterally any substantial distance beyond the end of the rockshaft I0, an unusually compact unit is achieved in which adequate clearance is provided between the various moving elements of the control linkage. This arrangement therefore nds particular utility in looms wherein it is desired to employ hydraulic check units for checking the shuttle throwing or shuttle catching movements of the picker stick. With the described arrangement, a hydraulic check unit may be conveniently mounted within the space dened between the arm portions I3b and I3c of the secondary bracket I3. It will be observed that such space is substantially free from interference with any of the components of the control linkage throughout the normal range of movement of the picker stick II.

It will, of course, be understood that various details of construction may be modined through a wide range without departing from the prin ciples of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. A linkage for controlling the movement of a picker stick oi a loom comprising a primary bracket adapted for securement to the rock shaft of the loom, said primary bracket defining a pair of vertically spaced pivot bearings overlying the end of said rock shaft, a secondary bracket of generally U -shaped connguration having its base portion adapted for scour-ement to a picker stick and disposed with the portions thereof projecting toward said primary bracket, said arm portions of said secondary bracket being suiiiciently laterally spaced to straddle said primary bracket, a rst pair of aligned pivot bearings respectively formed in the lower part of said arm portion, a second pair of aligned pivot bearings respectively formed in the upper part of said arm portions, a pair of first links pivotally connected between the lower pivot bearing of said primary bracket and said lower pivot bearings of said secondary bracket, and a pair of second links pivotally connected between the upper pivot bearing of said primary bracket and said upper pivot bearings of said secondary bracket, said pairs of links being constructed and arranged to control the movements oi s i" i stick to shift the shuttle-engaging portion thereof along a substantially straight line 2. A linkage for controlling the movement of a picker stick of a loom comprising a primary bracket adapted for securement to the rock shaft of the loom, said primary bracket dening a pair of vertically spaced pivot bearings overlying the end of said rock shaft, a secondary bracket of generally U-shaped conguration having its base portion adapted for securement to a picker stick and disposed with the arm portions thereof projecting toward said primary bracket, said arm portions of said secondary bracket being sufiiciently laterally spaced to straddle said primary bracket, a nrst pair of aligned pivot bearings respectively formed in the lower part of said arm portion, a second pair of aligned pivot bearings respectively formed in the upper part of said arm portions, a pair of links pivotally connected between the lower pivot bearing of said primary bracket and said lower pivot bearings of said secondary bracket, and an additional pair of links identical to the rst mentioned pair of links pivotally connected between the upper pivot bearings of said primary bracket and said upper pivot bearings of said secondary bracket, said links and said pivot bearings being proportioned to control the movements of said picker stick to shift the shuttle-engaging portion thereof along a substantially straight line path.

3. A parallel motion picker stick linkage for a shuttle loom comprising a primary bracket defining a pair of generally vertically spaced pivot points, a `picker stick bracket arranged intermediate the primary bracket and a picker stick, said picker stick bracket defining a pair of generally vertically spaced pivot points substantially laterally displaced from the picker stick, a rst link between the uppermost of the pivot points of said primary bracket and said picker stick bracket, said first link being of a length less than the spacing dimension of the pivot points on said primary bracket, and a second link between the lowerrnost of the pivot points defined by said primary bracket and said picker stick bracket, said second link being of a length equal to the length of said rst link, both of said links arranged to preclude pivotal movement thereof through a vertical position.

1. A parallel motion picker stick linkage for a shuttle loom comprising a primary bracket deiining a pair of generally vertically spaced pivot points, a picker stick bracket arranged intermediate the primary bracket and a picker stick, said picker stick bracket deiining a pair of generally vertically spaced pivot points substantially laterally displaced from the picker stick, a first link between the uppermost of the pivot points of said primary bracket and said picker stick bracket, said first link being of a length less than the spacing dimension of the pivot points on said primary bracket, and a second link between the lowermost of the pivot points defined by said primary bracket and said picker stick bracket, said second link being of a length less than the length of said rst link, both of said links arranged to preclude pivotal movement thereof through a vertical position.

5. A parallel motion picker stick linkage for a shuttle loom comprising a primary bracket defining a pair of generally vertically spaced pivot points, a picker stick bracket arranged intermediate the primary bracket and a picker stick, said picker stick bracket defining a pair of generally vertically spaced pivot points substantially laterally displaced from the picker stick, a first link between the uppermost of the pivot points of said primary bracket and said picker stick bracket, said rst link being of a length less than the spacing dimension of the pivot points on said primary bracket, and a second link between the lowermost of the pivot points dened by said primary bracket and said picket stick bracket, said second link being of a length less than the spacing dimension of the pivot points dened by said picker stick bracket, both of said links arranged to preclude movement thereof through a vertical position.

GEORGE H. HUFFERD.

REFERENCES CITED The following references are of record in the iile of this patent:

UNITED STATES PATENTS Number Name Date 8,506 Perry Nov. 11, 1851 571,729 Paige Nov. 17, 1896 FOREIGN PATENTS Number Country Date 605,104 Germany Nov. 5, 1934

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