US1692870A - Sheep shears - Google Patents

Description

Nov. 27, 1928. 1,692,870

F. w. scoTT SHEEP SHEARS Filed Jan. 2l, 1927 Flllll lllllllllllllll`ll}\!s @mi www Patented Nov. 27, 1928.

UNITEDv STATES FRANK w. scorri, on KIRLAND, ILLINOIS.'

SHEEP sHEA'Rs.

Application 1ed`January 21, 192'?, Serial No. 162,423. l

rlhis invention relates to power-operated sheep shears, or other hand tools of a similar character, and has for its principal object the provision of a shear ofan improved design and construction wherein the cutter may be properly and accurately adjusted m its tension relative to the comb so as to cut properly the full width of the swath and also minimize the wear of the cutter and comb, and result generally in a more smoothly and quietly operating tool, and O'ne which will give far betterI and longer service than those heretofore available.

More specifically stated the present invention provides a vibra-tor member trunnioned in the frame of the tool for its vibratory or oscillatory movement, anda tension member Carried thereby to move therewith as a unit, the tension member having rocker mounting intermediate its ends on' the vibrator member and bearing at its forward n end against the cutter to press the same against the comb, the rearward end intersecting the trunnion axis of the vibrator member and having an adjustable set screw bearing against its under side at this point to adjust the pressure of the forward end downwardly on the cutter. l The tension member is forked at its forward end so that the spread lingers thereof engage the cutter at separated points in the arc of its reciprocation and is, furthermore, capable of rocking laterally with respect to the vibrator member so as to accommodate the cutter accurately to the comb throughout its sweep. This, of course', makes for a smoothly operating tool and minimizes wear, and is far superior to the impractical and ui'iworkmanlike design incorporated in tools heretofore where the arm actuating the cutter also served to apply tension thereto, in which case the design neces sitated a wabbly mounting of the arm which caused excessive wearing of the cutter and comb and, of course, premature dullness of the teeth and generally unsatisfactory operation, The tension adjustment secured by the screw bearing against the rearward end of the tension member1 is also far superior' to the tension adjustments used heretofore,

since the screw in oscillating with the vibra-y tor member and tension member has no tendency to loosen or tighten after ythe proper adjustment of tension has been made. In earlier designs of shears the adjustment usually provided involved an adjusting nutY or the like which'did not oscillate with the vibrating part and the vibration always had a tendency to change the a'djustmentand it was, therefore, diiiicult to keep the proper tension on the cutter. l 1

My invention presents these and other ad# vantages over prior constructions as will appear more clearlyin the following specification in which reference is made to the ac` companying drawing wlierein Figure l is a view partly in `plan and partly in section of a powerdriven shear of the kind referred to incorporating 'the improvements of my invention. This view is taken approximately on the line l-r1 of Fig. 2; Y y

Fig. 2 is a central vertical longitudinal section 'taken onthe line 2-.2 of Fig. l; and

Fig. a front end view. t

rlhe same reference numerals are applied to corresponding parts in the three views.

The sheep shear illustrated, in common with other, shears of a similar type, com-y j'nises a frame 5 providing' a handle portion 6 by `which the tool is graspedvfor use, the

`latter being hollow and providing a bearing for the terminal driifing element 7 driven in the usual manner by connection with a iieX-A ible drive `shaft at the outer end ofthe handle, as is well known'in this art.v ,The element terminates'within the housing; S. in a crank portion Qhaving a ball l() swiveled on the crank pin thereof andjarranged for operation in a ball race provided, ingthe cross'- headll whereby toproduce vibrato-ry Inovenient of the actuator for the cutter l2 and reciprocate thel same relative to the comb 13. rlhe construction thus far generally described is common to many types of sheepv shears available at Athe present time. The shear of the present invention, however, dis# tinguishes from' these earlier toolsas was stated above, by providinga cutter actuatorof novel constructionv and one wherein'the cutter may be properly and accuratelyten, sioned and will always maintain its adjustment without being affected by the vibratory action of the cutter actuator.' This` novel actuator is indicated generally by the refer-- ence numeral 14' and' will now be described indetail. y

The cutter actuator comprisesavibrator member 15' and a tension member 1G. The member vl5 has the cross-head 11 formedy preferably integral lwith the rearward end thereof and extends forwardly towardth.v` cutter l2, the forward end being conformed to provide a yoke 17 having a bearing opening, 18 therein for the reception of the intermediate portion of the tension member 16. The vibrator member has axially aligned trunnions 19 and 2() provided by the extremities of a tube 21 fitting through an opening 22 in the body of the vibrator member, the tube 21 having a driving fit in the opening 22 or being otherwise suitably iixed in position therein as by swedging. The trunnions 19 and 2O are received in journal bearings 23 and 24 provided in a plug 25 and bushing 26 suitably threaded in openings in the walls of the housing 8. Ample bearing is, therefore, provided for the vibrator member and vibration and its accompanying wear will be reduced to a minimum. The end thrust of the trunnion 19 resulting from the tension placed upon the cutter 12, as will presently appear, is assumed by the ball end 27 of a set screw 28 threaded within the trunnion 19. The ball end 27 engages within a socket 29 provided therefor in the plug and lubrication is afforded for both the thrust bearing at 29 and the journal bearing at 23 through an oil openc ing 3 0. yThe latter communicates with an oil well 81 provided in the top of the plug 25, the well being furnished with oil through an oiler opening 32 in a cap 33 threading on the plug 25, the opening being normally sealed by a ball closure 34 held in place by a coiled compression spring 35. The set screw 28 is preferably held against turning by a pin 36 passed therethrough and received at its ends in openings 37 provided in the trun nion 19. When there has been a certain amount of wear at the thrust bearing 29 the set screw 28 may be adjusted to take up any end play by engaging a screw driver in the slot 38 from the remote end of the tube 21, the pin 36 being, of course, removed to permit such adjustment and being replaced after the same is made.

The tension member 16 has a rocker mounting in the bearing opening 18, previously referred to, so as to have capacity for endwise and lateral rocking movement. The capacity for endwise rocking movement permits the application of pressure on the cutter 12 by the forward end of the tension member while the capacity for lateral rockingmovement, as will appear shortly, permits the tension member to accommodate the cutter 12 to the comb 125 throughout the length of its sweep. The tension member 16 for the latter reason is forked at its outer end and has the spread lingers 40 thereof provided with pointed ends 41 for reception in holes 42 provided in the prongs of the cutter 12. rPhe cutter lemployed may have two, three or more prongs. The tension member thus engages the cutter at separated points 1n the are of its reciprocation and, by reason of its capacity for lateral rocking movement, accommodates the cutter to the comb throughout its sweep, which, of course, makes for smooth and easy operation of the tool.

tersects .the fulcrum axis of the vibrator member and extends through an opening 43 provided in the wall of the trunnion 20. An adjustable set screw la threading within the trunnion hasl a ball end l5 to engage a complementary recess 46 provided in the under side of the tension member 16. Gbviously the tightening ofthe set screw all forces the rearward end of the tension member 16 upwardly and rocks the same in its bearing 18 se that the forward end is forced downwardly and presses the cutter 12 against the comb 1?, the pressure on the cutter being equalized by reason of the spread lingers Ll0. A coiled compression spring et? The rearward end of the tension member 16 inacting between the inner end of the set screw 28 and the top of the tension member 16 at the rearward end of the latter serves to hold the tension member in close Contact with the set screw 4 4 so that any tendency to rattle or chatter is entirely eliminated and very lli;

close and accurate adjustment'of the tension on the cutter may be made. also raises the front end of the tension member when the screw 44 is loosened to release the cutter 12 for replacing the cutter. A change in cutters can thus be made with little difficulty or less of time.

The operation of the tool is believed to be apparent from the foregoing description, namely, that the tension member 16 always moves with the vibrator member 15 as a unit in the vibratory or oscillatory movement of the lat-ter in operation. The adjustment as to tension secured by the set screw 411 may be accomplished with ease and facility to secure the finest graduation in tension desired and, by reason of the equalizing action of the forked end of the tension member, the action of the cutter will be smooth and even from end to end of its sweep and ypositively devoid of jerkiness, chattering, and vibration and the accompanying noise. rlhe fact that the set screw lil threads within the trunnion 2O and is, therefore, caused to oscillate with the vibrator member and tension member eliminates a very common dilliculty met with in tools of the present character, namely, that of the tension changing by reason of the vibratory action. There is positively nothing which in any way could. affect the adjustment after it is made. A further feature worthy of mention is that the present tensioning means obviates the necessity for parts projecting above the actuator, or below The spring it, which parts in previous constructions` were objectionable in that they madeit difficult in shearing as, for example, about and between the horns. Furthermore, attention is called to the ample bearings provided for llo wherein the 'yoke on the vibrator member provides a support for the tension member permitting both endwise and lateral rocking movement of the latter for the purposes described,

8. In a structure asset forth in claim 5, the provision of a compression spring disposed within the vibrator member and acting against the upper side of said tension member at the rearward end thereof whereby to hold the same downwardly against the set screw.

9. In a shearing tool of the character described comprising a frame having a part for holding the tool, a fixed cutter comb on said frame, and a reciprocating cutter cooperating therewith, a vibrator member fulcrumed in said frame for vibratory action, a tension member bearing at its forward end on top of the reciprocating cutter and mounted on said vibrator member for movement therewith in the operation of the latter, said tension member extending rearwardly from the cutter to intersect the fulcrum axis of the vibrator member, a bearing on said Vibrator memberfspaced from the fulerum axis thereof wherein said tension member is mounted for lateral and endwisejroelring movement so that the forward end of the latter may be adjusted up and down and laterally with respect tothe cutter properly to tension the latter relative to the comb and accommodate itself thereto, and means disposed on the fulcrurn aXis of the vibrator member to bear against the tension member whereby to urge the forward end of the latter downwardly to tension the cutter.

10. In a structure as set forth in claim 9 wherein the last mentioned means is positive in its action in communicating a Vgiven amount of adjustment to the rearward end of said tension member, the provision of aV spring acting in the reverse' direction against said tension member arranged to yield to iermit the aforesaid adjustment.

1l. In a structure as set forth in claim 5 wherein the upper trunnion has a set screw adjustable therein serving as an end thrust bearing for said trunnion Vand arranged when adjusted to take up end play, a compression spring. `disposed in said trunnion bearing at one end against the inner end of the set screw and at the other end against the tension member at the rearward end of the latter whereby yieldingly to force the latter downwardly toward the set screw in the lower'trunnion. i

l2; A structure as set forth in claim 5 wherein the frame has cut-out portions permitting the entry and removal of the upper and lower trunnions of the vibrator member,

and wherein the bearings for said trunnions comprise plugs threading in openings provided in said frame intersected by the aforesaid cut-out portions, said plugs when threaded in place serving to retain the vibrator member in the frame by its trunnions.

In witness of the foregoing I aiiix my signature.

. FRANK W. SCOTT.

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