US2333092A

US2333092A - Variable change speed hoist

Info

Publication number: US2333092A
Application number: US382923A
Authority: US
Inventors: Trevor O Davidson
Original assignee: Bucyrus Erie Co
Current assignee: Caterpillar Global Mining LLC
Priority date: 1941-03-12
Filing date: 1941-03-12
Publication date: 1943-11-02
Anticipated expiration: 1960-11-02

Description

T. o. DAVIDSON v2,333,092

VARIABLE CHANGE SPEED HOIST Filed March l2, 1 941 Nov. 2, 1943.

IVENTOR.

ATTORNEY Patented Nov. 2, 1943 VVARIABLE CHANGE SPEED HOIST Trevor O. Davidson, Milwaukee, Wis., assigner to Bucyrus-Erie Company, South Milwaukee, Wis., a corporation of Delaware Application March. 12, 1941, Serial No. 382,923

Y Y 6 Claims.

My invention relates to new and useful improvements in hoists, more particularlyto the hoisting mechanism of lexcavators of the type having a boom and an outward digging clipper mounted on the end of a handle, which handle is reciprocable with respect to a point on the boom known as the shipper shaft, the dipper being movable in a circle about this point as a center.

The hoisting line usually extends from a winding drum on the main frame of the excavator, over a sheave on the outer end of the boom, to the clipper and handle, and thence over another sheave on the boom to an anchorage on the boom.

Frequently it is desirable that the operator of such an excavator be able to change the speed of hoisting the dipper, and be able to make this change of speed at selected points of the hoisting cycle. Thus when the dipper is digging, it is desirable to move it at low speed with high applied force; and when the dipper is hoisting, or is doing light digging, it is advantageous to move the dipper at high speed with lower applied force. Furf thermore, since digging conditions differ on each job, the point in the hoisting cycle at which the speed is changed should be variable, but once the point has been determined for any given job, the change of speed should thereafter be automatic throughout that job. Lastly, the means for accomplishing the change of speed and for varying the point of change speed should be simple and l inexpensive.

Accordingly it is the principal object of my invention to provide, for control of the hoisting line,

the novel combination of a multiple-diameter winding drum and a variable anchorage, whereby the hoisting speed may be changed automatically,

and the point of change speed may be varied.

Another object resides in the provision of v means for Varying the point-oi` change speed, which means is independent of the means for changing hoisting speed, and is simple to construct and to operate.

In addition to my principal objects, I have worked out a number'of novel and useful details, which will be readily evident as the description progresses.

My invention consists in the novel parts, and in the combinations and arrangements thereof, which are dened in the appended claims; and of which two embodiments are exemplied in the accompanying drawing, which is hereinafter particularly described and explained.

Throughout the description, the same reference number is applied to the same member or to similar members.

Referring to the accompanying drawing, it will be seen that:

Figure 1 is a conventionalized side elevation of an excavator equipped with my invention, showing the dipper in two positions. In the digging position, the clipper and the hoisting-line are shown by full lines; in the hoisting position, they are'shown by dotted lines.

Figure 2 is a rear elevation of a two-diameter drum, taken along the vlines 2 2 in Figure 1. This is one embodiment of a part of my invention.

Figure 3 is a similar rear elevation o-f a tapered drum,'which is another embodiment of the same part of my invention.

Referring now more particularly to Figure 1, we see that I have illustrated an excavator or power shovel of a conventional type, omitting, however, certain details as not essential to an understanding of the invention. Well known details of this type of excavator are: the main base II which is ordinarily revolvable o-n a propelling traction mounted base (not shown) ;V an upwardly inclined boom IZ pivoted at its foot to the base II; a suspension (not shown) for the boom; a clipper handle I3, carrying at its outer end a dip per I4; and a power driven shipper shaft I5 journalled on the boom for eiiecting reciprocation of the dipper handle. The method of driving this shipper shaft is immaterial to the present invention. Thus it may be driven by an engine I8 located .adjacent toit (as shown in Figure l), or by any other conventional expedient. A hoisting Winch or drum I'I, driven by anv adjacent engine I8, is 'shown mounted on the base, although it may be mounted on any other part of the machine which in turn is supported by the base. A hoisting line I 9, anchored andwrapped upon this hoisting-drum, is trained over one of the sheaves 20 at the outer end of the boom, to a sheave 2| on the clipper, and thence over another sheave 20 to an anchor 22 on the boom. The hoisting line may consist cf a rope, chain, or other flexible tension member.

A principal element of my novel hoisting mechanism is the multiple-diameter hoisting drum I'I, two embodiments of which are shown in Figures 2 and 3. In Figure 3 the barrel of the drum is tapered and provided with a continuous groove 23 for guiding the hoisting-line from the'small to the large end of the drum and vice versa. In Figure 2 the drum is formed with two

portions

24 and 25 of different diameters. The groove 26 at the large end 24 of the drum is connected with `the groove 21 at the small end 25 thereof by a transitional groove 28. In both types of drum the hoisting-line I9 is anchored at 33 on the small low speed end 25 of the drum and is wound on the drum up over the large end 24. The direction of winding depends on the direction in which the groove is cut. For example, in Figures 2 and 3 the grooves are yshown running clockwise from the small to the large end (considering the 'drum as viewed from the right as in Figure 1). Winding the hoisting-line up on the drum eiectsav change from low-speed high applied` force `to high-speed low applied force. Ifthedriunillustrated in Figure 2 is employed, this change occurs suddenly at a point in the-hoistingcycle which.

is determined by the adjustment ofthe variable anchorage which is the second important element of my invention.

In Figure 1 one form of variable anchorage is shown on the upper part of the boom. The illus- :itrated form- 'of .anchorage 'consists 1 of 1a. plate 1,2 9

mounted lengthwise on the boomlandperforated 'with longitudinally spaced: holes v3!) iorr'eceiving a removable pin or bolt 3| to whichthef hoistingfline" l 9: is "dead ende'd. Itiis funderstood, however, @that my" invention i is fnot limited to 'this :particular 'fform y'of variable f-anchorage,v fbut coverspany :adjustable I.or operable device, preferably rindezpendent Aoffthe Ahoistingrneans,A` whereby the working portion of the hoisting-linefmay' be' shortened or 'lengthened Changing 'the point of anchorage,

.'byinserting theanchorage pin or bolt in another "hola-'or byadjusting or operating any other 'form eofrvariable .anchorage idevic'e, 'effects a Vchange in @the pointof Xchange speedin the hoisting'cycle, 1

and also shifts the point airone-wear.

'znwFigure '-1`full lines showt'hedipper in'v digging posit-ion, with 'the hoisting line 1on the'low speed small diameter portion ofthe drum' and dotted t lines 'show 'the clipper in'hoistingposition, 'with ythehoisting'line.onthe highspeed large 'diameter ,iportion of the drum. If digging is light, the dip- )per -may beioperated at high-speed in both fthe `digging andhoistin'g positions by `vdead-ending the :hoisting-line at the outer v'anchorage f32, since the point :of change speed will then bevat the Ilowest fextremelof Vthe hoisting cycle,and onlyline'wound 7onthe large diameter portion 24ofthe'drurn` will fbefactive. Conversely, if vthe ldigging is heavy, @the-dipper maybe voperated at low `speed in both ldiggin'gandhoistingpositions by dead-ending the :hoisting-line at the inner'anchoraga 'so that'only Vline wound on the small `diameter portion `25 of the .drum will 'be active.

Havingnow described-'and illustrated one yform Vof'my inventio-n,'I'wish it tobe understood that :my invention is` not :to be limited to the Yspecific .lfcrm lor arrangement of parts .herein-described and shown, except as lsp'ecilically coveredby my claims.

AI claim:

1. In a power shovel, Ithe Vcombination tof: Va boom; 4guide sheaves on the boom; a ydipper fhandle; a dipper carried by thehandle; means for reciprocating the clipper handle; a ymultiple 'diamet'erhoisting drum formed with'aoontinuous'cable-guiding-groove; anda hoist rope having a ilive `end and a dead end, its live bend being iattached to and wrapped upon the hoisting drum,

trained over lthe guide sheaves, and connected with the dipper, and its dead end being attached to an anchor selectively positionable in a number of positions, to vary what diameter of the drum is eiective in different portions of the hoisting cycle, by means including adjustable pin connection means mounted along the length of said boom for anchoring the hoist rope at any one of a plurality of longitudinally spaced points along vsaid boom.

2. In a power shovel, having: a boom, a dipper handle, and a dpper carried by the handle, the

vcombination therewith of: a flexible hoist member having a live end and a dead end; a winch wcapable, lata constant speed, of imparting variable speed yto the live end of said hoist member, de- `.pendent on the degree of travel thereof; and, in-

dependent of such winch, an anchor for the dead end of said hoist member, said anchor being selectively positionable in a number of positions to vary what degree of travel occurs in different portions of the hoisting cycle.

3. In ua hoist, 'the combination of: a load fhandlin'gimeans; a flexible. hoist member having a live end and a dead end; a multiple diameter "hoisting ldrum for imparting variable speed to the live end'of said hoist member; and an anchor for the dead `end of said hoist member, said anchor fleeing selectively positionable in a number of positions to `vary what diameter of the drum is effective in different portions of the hoisting cycle.

4. In `a power shovel, v'the combination of a boom; guide sheaves on the boom; a dipper handle; 'a clipper carried by the handle; means for reciprocating the Clipper handle; a multiple .diameter hoisting drum formedv with a continuous cable-'guiding groove; and ahoist rope having 'a live end'and 'a dead end, its live endbeing a'ttached to the small'diameter end of said Ydrum and wrapped upon the small 'and largeV diameter portions of `said hoisting drum, trained over the ,guidesheaves, and connected with thedipper, and 'its dead endY being'atta'ched toadjustable pin'conr`ne'ctio-n means mounted along'the length of said boom for anchoring the hoist rope at anyone of la plurality of longitudinallyspa'ced points along choring the iiexible hoist member at any one of a plurality of longitudinally spaced points along said bo-om.

6. In a hoist, the combination oi t' load handling means; a exible hoist member having a live end and a dead end; a multiple diameter hoisting drum for imparting variable speed to the live end of said hoist member; and an anchor yfor one end Vof said hoist member, said anchor including adjustable pin connection means for anchoring said hoist member at any one of a plurality of spaced points.

rTRES/ORv O. DAVIDSON.