US2009453A

US2009453A - Grapple

Info

Publication number: US2009453A
Application number: US713006A
Authority: US
Inventors: Mason D Pratt
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-02-26
Filing date: 1934-02-26
Publication date: 1935-07-30
Anticipated expiration: 1952-07-30

Description

M. D. PRATT July 3@, 1935.

GRAPPLE 2 Sheets-Sheet l I VHHHL Filed Feb. 26, 1954 //VVE/Y70/. MASON D. PRATT.

GRAPPLE Filed Feb. 26, 1934 2 Sheets-Sheet 2 MIVE/YTQ/e. MASON D. PRATT.

M: Ante/YE Patented July 30, 1935 UNITED STATES PATENT OFFICE 10 Claims.

My invention relates to improvements in grapples for use in handling large, irregularly shaped, masses, such as rocks, and the like, wherein a spider, having at least three equally spaced radial arms, operates in conjunction with the usual hoisting means and a crank lever loosely mounted in connection with each arm to permit said levers to automatically and independently adjust themselves to more effectively fit and grip 5 the surfaces of an irregularly shaped mass whereby said mass may be elevated or otherwise handled.

' The primary object of the present invention is to provide a new and improved grapple for handling large, irregularly shaped, masses, such as large rocks, boulders, and the like.

Another object is to provide a new and improved grapple of the character described, having improved means for automatically and independently adjusting the outer ends of a plurality of crank levers to more effectively fit and grip the surface of an irregularly shaped mass to facilitate handling said mass.

A further object is to provide a new and improved grapple in which a plurality of freely or loosely mounted crank levers are each pro vided with a plurality of fulcrum seats and in which lifting means are provided for initially moving said levers so that one of the fulcrum seats of each lever will first engage its respective fulcrum and then further be moved by said lifting means to cause the outer ends of said levers to first fit then grip an object whereby said object may be more effectively elevated or otherwise handled;

A still further object of the present invention is to provide a new and improved grapple of the character set forth in which a plurality of loosely mounted crank levers automatically and independently adjust themselves to more eifectively fit the surface of an irregularly shaped mass when lowered thereonto, and operate with a universally connected hoisting or lifting means to automatically swing the center of gravity of said mass directly under said hoisting means.

I accomplish these and other objects by means of the improved grapple disclosed in the accompanying drawings, in which Fig. 1 is a sectional View taken on line I-I of the broken plan view of Fig. 3, in the direc tion indicated;

Fig. 2 is a broken detail of the universally connected hoisting means; 7 g Fig. 3 is a broken plan view of thedevice, partly in section; and

Fig. 4 is an enlarged transverse sectional view taken on line 44 of Fig. l of the drawings, in the direction indicated.

Referring to the drawings, the numeral I is used to designate, in general, a spider having, in the preferred form of the invention, at least three equally spaced and longitudinally slotted radial arms ,2, within the spaces or slots 3 of which are mounted the crank levers 4, whose outer ends 8 are provided for engaging an irregularly shaped mass, boulder, or rock, 'I.

The outer end of each arm 2 is provided with a fulcrum pin 8 arranged to be engaged by any one of a plurality of what I term fulcrum seats 9 arranged intermediate the ends of the levers 4 and preferably adjacent the outer end of said levers d, as disclosed in Fig. 1 of the drawings.

The spider I is provided at the inner end of each arm 2 with a double cam track II, as disclosed in Figs. 1 and 4 of the drawings.

The inner ends of the levers 4 are each provided with a pair of rollers I2 which ride upon these tracks II for a purpose and in a manner hereinafter more fully set forth.

The inner ends of said levers 4 are connected, by means of universal joints I4, and pivotally connected links I5, to similar universal joints I5 within a lifting head I! provided with a pair of lugs I8, between which lugs I8 is a third uni-' versal joint or connection I9 connected by a pair of pivotally connected links 2| to a bolt 22, which bolt 22 is engaged by a clevis, cable, or other connection, not shown, to any suitable. hoisting mechanism or means, not shown.

The lifting head I! is provided upon its underside with a preferably conical projection 23 arranged to fit within a similarly shaped recess 24 and normally held therein by means of a suitable spring controlled latch 26 having a line 21 extending to a remote operator, not shown.

The outer upper ends of the crank levers 4 are provided with apertured extensions 28 above the plurality offulcrum seats 9, which extensions 28 serve as limiting stops to limit the lowermost position of said levers 4. Lines 29 extend from these extensions 28 to a lifting source not shown.

In operation:

The spider I is lowered directly over an irregularly shaped mass I by means of the lines 29 attached to the extensions 28 of the levers 4; While being lowered by means of these lines 29, the

lifting head I! is preferably attached as shown in Fig.1 of the drawings, and the weight of the spider I is supported by the fulcrum pins 8 resting upon limiting stops 3] on the outer endsof the levers 4, as disclosed in Fig. 1 of the drawmgs.

When the spider I has been lowered to a point adjacent the irregularly shaped mass 1 to be lifted, further progress of said spider is arrested while the levers 4 are released or lowered by the lines 29 until they engage said mass or irregularly shaped object 1.

As the rollers 12 upon the inner ends of the levers 4 are resting within inclined flanges 32 formed upon the spider l and immediately below the double cam track H, the said levers may swing downwardly upon the axis of the rollers l2 and as the line of the fulcrum seats 9 is arranged concentric with the axis of said rollers, the levers 4 may move downwardly without permitting any of said fulcrum seats 9 to engage the pins 8.

Thus, it will be seen that each lever 4 will automatically and independently adjust and fit itself into engaging relation with the irregular sides of the mass or object 7. When this is accomplished, the line 21 is operated to release the spring controlled latch 26 and the liftin f Qad i1 is then elevated, in turn elevating the inner ends of the crank levers 4 until the raised portions of the cam tracks ll engage the rollers l2 and thereby move the fulcrum seat 9 of each lever nearest its respective fulcrum pin 8, into engaging relation with said pin 8, as disclosed in dotted lines in Fig. 1 of the drawings.

The raised portions of the cam tracks H are arranged concentric with their respective fulcrum pins 8, as indicated by the radial lines in Fig.1, so that when the pin 8 is engaged by one of the seats 9, it becomes a pivot or axis for that lever and is held in such engaging relation by the concentric relationship of said raised portions of the tracks II to said pin 8, as theinner end of the lever 4 moves upwardly- Therefore, as the'lifting strain is placed upon the lifting head I! and the lines, 29 are slaeked off, said liftingstrain'upon the inner ends of the levers operates to move the outer ends 6 thereof into gripping engagement with the mass or object "I, regardless of any variation in the several positions relatively to each other which the lower or outer ends of the levers 4 may The mass 7 may then be lifted.

When it is desired to r elease the mass or object 7, thelifting head H is lowered or returned into engaging relation with the spider! which action will depress or lower. the inner ends-of the crank levers 4, thereby moving the outer ends of said levers dout'wardly and disengaging the mass 1,

The universal connections are provided between the inner endsof the levers Land the lifting head I? and the links 2| above it, in order that thecrank levers 4 may move independently of each other and the spider within certain limits, to. adjust or fit themselves to the irregularly shaped mass in order to secure a. more effective.

gripping engagement of said levers with said irregularly shaped mass.

' Having thus described my invention, I olaim--. 1. A grapple comprising a plurality of fixed fulcrums; and a plurality of gripping crank levers, one for eachfulcrum, said levers each being provided with automatically adjustable fulcjrum' seats arranged to engage said fulcrums whereby said. levers may move to moreeffectively fit and thereby effectively grip anirregularly shaped mass.

'2 A. grapple comprising a plurality of fixed fulcru ns; and a plurality of gripping crank le-- vers, one for each fulcrum, each of said levers being provided with a plurality of fulcrum seats; and means for preventing engagement of any seat with its fulcrum before said levers are moved to grip an object whereby said levers may be positioned to more effectively engage an irregularly shaped mass.

3. A grapple comprising a plurality of fixed fulcrums; a plurality of gripping crank levers, one for each fulcrum, each of said levers being provided with a plurality of fulcrum seats; means for preventing engagement of any seat with its fulcrum before said levers are moved to grip an object whereby said levers may be positioned to more effectively engage an irregularly shaped mass; and means for moving said levers to move the fulcrum seats thereon nearest their respective fulcrutns into engaging relation with said fulcrums.

e. A grapple comprising a spider having at least three spaced arms; a fulcrum pin mounted at the end of each arm; and a crank lever, one for each arm and pin, universally andslidably connected to said spider at its inner end only, and provided with a plurality of fulcrum seatsfor engaging its respective pin whereby said levels may be automatically adjusted before gripping an irregularly shaped mass to more efl'ectively grip said mass when later moved into gripping engagement therewith.

5. A grapple comprising a spider having at least three spaced arms; a fulcrum pin mounted at the end of each arm; a crank lever, one for each arm and pin, universally and slidably connected to said spider at its inner end only, and provided with a plurality of fulcrum seats for engaging its respective pin whereby said levers may be automatically adjusted before gripping an irregularly shaped mass to more effectively grip said mass; when later moved into gripping engagement therewith; and means for moving the levers to move each fulcrum seat nearest its respective fulcrum into engaging relation with said fulcrum 6. l- 'he combination with a grapple and fill-- crum pin thereon, of a crank lever universally connected at its inner end, only, to said grapple and, having a plurality of fulcrum seatsintermediate its ends and disengaged from said fulcrum whereby said lever may be positioned to more ef-.

fectively grip an irregularly shaped mass before fulcrum whereby said lever may swing uponits:

connection to automatically fit an irregularly shaped; mass before being moved into engaging, relation with its-fulcrum and before being moved to grip said mass; and means for moving said,

lever first, with the fulcrum seat nearest the fulcrum into engagementtherewith and then.moving saidlever into gripping engagement withsaid mass. 7

8. A grapple comprising a, spider having at least three radially spaced arms; a fulcrumpin mounted, upon the end of eacharm; a crank lever universally mounted in connection with each arm andprovided intermediate its ends with a plurality of fulcrum seats: arranged ad jacent and inspaced relationto the fulcrunrin their respective arms wherebysaidleversmay' automatically and independently move to fit an irregularly shaped mass; and means for moving said levers to engage their fulcrum seat nearest their respective fulcrum to said fulcrum and then to move said levers into gripping engagement with said mass.

9. A grapple comprising a spider having at least three equally spaced arms; a fulcrum pin mounted upon each arm; a crank lever loosely mounted in connection with each arm and provided intermediate its ends with a plurality of fulcrum seats; means for simultaneously disengaging said fulcrum seats from their respective fulcrum pins whereby said levers may be position to independently fit an irregular object; and lifting means for moving, first the fulcrum seat of each lever nearest its respective fulcrum pin into engaging relation with said pin and then to move the outer ends of said levers into gripping engagement with said object.

10. A grapple comprising a spider having at least three equally spaced and longitudinally slotted radial arms; a fulcrum pin mounted at the outer end of each arm; a crank lever loosely mounted within each slot and having a plurality of fulcrum seats arranged adjacent each outer end whereby each lever may be automatically and independently adjusted to fit an irregular object to be engaged by said arms; a cam track arranged adjacent the inner end of each slotted arm and having a raised portion arranged concentric with the fulcrum pin in said arm; rollers on the inner end of each crank lever and engaging said track; and lifting means universally connected to the inner ends of the crank levers for moving said inner ends to move the fulcrum seat on each lever nearest its fulcrum pin into engaging relation with said pin whereby the outer ends of said levers may be moved to fit and grip an irregularly shaped object.

MASON D. PRA'I'I.