US1644743A - Grab - Google Patents

Description

. A- E. NORRIS GRAB 5 Sheets-Sheet Filed Jan. 17, 1921 Invenioa":

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dd qq dd ad- 1 A. E. NORRIS GRAB F1144 Jan, 17. 1921 5 sheeis-snet 4 Ii 1:1 I i. r

\IIIIIIIIHA scale on line 9-9 of Fig. 2;

Patented st. 11, 1927..

stares ALMS E. EJ031313, E BROOII ZLINE. IfiSSAGI-IUSETTS.

GRAB.

Application filed January 17, 1921. Serial No. 437,650.

This invention relates to grabs, being more particularly Concerned with clam shell buckets of the lever type, and aims to in crease the eliiciency of grabs of this class and to improve their construction in gen eral. 7

My invention will be best understood by reference to the following description, when taken in connection with the accompanying drawing of one specific embodiment thereof, while its scope will be more particularly pointed out in the appended claims.

In the drawings: 7

Fig. 1 is an end elevation of. a grab exemplifying my invention; 1

Fig. 2 is an end elevation of the grab as it appears when open;

Fig. 3 is a sectional view online 38 of Fig. 2;

Fig. 4 is a sectional view on line 44 of Fig. 2;

Fig. 5 is a sectional View online 55 of Fig. 1

Fig. 6 is a side elevation of the viewed from the right-hand side of Fig. 1; Fig. 7 is a sectional view at an enlarged scale on line 7.7' of Fig. '1;

Fig. 8 is a sectional view at an enlarged scale on line 88 of Fig. 6;

Fig. 9 is a sectional view at an enlarged Fig. 10 is a sectional view at an enlarged scale on line 1010 of Fig. 1;

Fig. '11 is a sectional View at an enlarged scale on line 1111 of Fig. 1; and

Fig. 12 is a sectional view at an enlarged scale on line 1212 of Fig. 1.

Referring to the drawings, and to the embodiment" of my invention which I have selected for exemplification, having particular reference to Fig. 1, I have shown a grab havinga pair of scoops 14 andv 14E provided with jaws 15 and 15, the latter being suitably secured as by rivets 16 and 16' to end plates 17 and 17. The'plates at one end are united to those at the other end by curved plates 18 and 18 in any usual manner.

The scoop 1-1 is provided with a pair of hinges 19 suitably secured thereto as by rivets 20, and the scoop 14 is provided with a pair of similar hinges 19' secured thereto by rivets 20. In the present example, the hinges of one scoop are connected to those 'of the ether scoop by a hinge-pin 21,

shown in Fig. 9, appropriately held in place 5 therein as by nuts 22 threaded onto the ends thereef, and conveniently held against acci dental turning movement by bolts 23, which extend through the nuts and through the hinge-pin. The latter isv preferably held against turning movement in one pair of hinges, herein the hinges 19, as by bolts' 2e (see Fig. 9) which extend through the hinge-pin as well as; through the bosses of the hinges, while on the other hand the hinge-pin turns in the bosses. of the hinges 19', the latterv being preferably provided with renewable bushings 25, in which the hinge-pin turns. The bushings may be held against turning movement in the hinges as by providing them with keys or feathers26 (see Fig. 10) received in key-ways 27 pro vided inthe hinges. For conveniencev inre moving the bushing should it become neces sary, it is herein provided. with an L-shaped recess 28 to receive a suitable hook-like implement by means of which the bushing may be withdrawnin an axial direction. Suitable means of lubrication are provided,h'erein an oil hole 29 normally closed by a filling plug 30 said hole feeding oil to'a groove 30 extending lengthwise of the bushing. It should be evident that since the hinge-pin is fixed with reference to one pair of hinges and turns in the bushings of the other, the latter receive all of the wear and if renewed from time to time ensure aproperworking pivotal joint. 7 i The hinges are preferably provided with suitable means for limiting the opening movement of the scoops,herein two pairs of lugs 31 and 31, conveniently formed on the hinges 19 and 19, respectively, and provided with chambers 32 and 32 to receive suitable cushioning means, such as wooden plugs 33 and 33 (see Fig. 8-), whose end grain is presented to the impact.v For con.- veniencein driving these. plugs out, when their abutting ends are worn, the lugs 31 and 31 are hereinprovided with openings 31 and 34.

The upper edges of the curved plates 18 and 18 are preferably reinforced by stiffeners 35 and 35 secured thereto bylr'ivets 3b and 36', said stiifenersherein beingprovided with integral brackets and 37, the latter being secured to the end plates liand ion it rivets 38 and 38, hite prefer bly 41 is provided with a key 42, which is rebolts 52 and 53 respectively extend.

ceived in a key-way 43 in one of the ears, and holds the pin againstturning movement with relation to the ears, while the link is provided with a bushing 44 in which the pinturns. Turning movement of the b'ushingwin the link may be prevented by providingthe bushing with a key or feather 45 received in a key-way 46 provided in the link. It should be understood that this construe tion is utilized in the case of the pivotal pins 41, as well as the pins 41.

The members of each pairof links converge toward their upper ends, where they are pivoted together by a pin 47 best shown in Fig. 11,-which is preferably fixed with relation to one pair of links and turns in the other. In the present example, the pivotal pin is held against turning movement in the links 40 by screws 48, and turns in the links 40', which are provided with suitable means of lubrication, such as oil holes 49 normally closed by filling plugs 50, said holes feeding oil to grooves 51 extending lengthwise of the pivotal pin. I a

The links 40 constitute a frame, and they are preferably rigidly secured to each other, as by tie- bolts 52 and 53 which extend there through, while the links are suitably spaced apart by several spacers, herein including pairs of bosses 54 and 55, through which 1%]6 1e links are further tied together by a bolt 56, towhich is attached a holding rope 57.

. In the absence of any means to hold the grab-closed, the scoop will naturally open .to the position represented in Fig. 6, their opening movement being limit-ed by the stops hereinbefore described. The closing move ment of the grab is accomplished by suitable closing means, herein including a closing rope'58, a series of sheaves 59, 60, 61 and 62, and a closing lever 63. In the present embodiment, the sheaves 59 and 61 are mounted to turn on fixed shafts 64 and 65. respec tively, on the links 40, while the sheaves and 62 rare mounted to turn ona fixed shaft 66. carried bytheclosing lever 63-. Preferably, the axis of the shaft 65 is inclined indicated in Fig. 7, thereby to give a good lead of the closing rope to the sheaves 60 and 62, as will be evident from an inspection of Fig. 7..

' Referring now to the closing lever 63, the

latter is provided with an elongated boss 67, best shown in Fig. 9, which is loosely mounted on the hinge-pin 21, but said lever isappropriately secured to the scoop 14 as bv bolts 68, which attach the lever to the stiffen-er It follows that swinging movement of the scoop 14 about the axis of the hinge pin 21 is accompanied by like swinging movement of the closing lever about such axis. The upper end of the closing lever is clam in screws 73 best shown in Fi 5.

As the lead of the terminal portion of the rope changes very radically during the operation of the grab, l have provided the closing lever with a curved ledge 74 on which the rope bends, and have provided one of the links 40' with a somewhat similar ledge 75, the la ter presenting an apertured lug 76, through which the rope may be led. Either arrangement of the rope may be employed, according to the amount of power required for the particular work being performed.

An important feature of my invention resides in the relationship of the pivots 21 and 47, with reference to each other and to the centers of pivots 41 and 41, or in other words with reference to the vertical median line XY of the grab. By reference to Fig. 1, it will be observed that the axis of the hinged pin 21 is offset from the vertical median line of the grab toward the right, as viewed in Fig. 1, that is to say, it is nearer tolthe center of the pivot 41. than to the center of the pivot 41, while the axis of the pin 47 is similarly, but to a much greater extent offset toward the left. The eflectof this isto give a much greater distance between the hingepin 21 and the links 40 than would otherwise be possible, and the result is a greatly increased power toward the end of the clos ing movement of the grab. The formula may be expressed as "follows: Let it be assumed that the lengthwise thrustof the links 40 upon the scoop 14 is represented by A, the distance from the axis of the hinge pin 21 to the lowest point X of the meeting edges by B, and the distance from said axis to the longitudinal median lineof the links in a directionnormal to the latter by G. Then the thrust A, multiplied by the distance G, divided by the distance B, equals the force applied to the jaw at the point X. Thus it is evident that the greater the distance C, the greater is the power of the closing movethereto, what I claim and desire by Letters venting accidental. escape of material from the grab. 1 1

Having thus described one embodiment of my invention, but without limiting myself Patent to-secure is:

l. A grab comprising, in combination, a pair of jaws hinged to turn about an axis laterally offset from the vertical median. line of the grab as viewed fromthe end of said axis, supporting links pivoted to each other to turn about an axis laterally offset from said line and pivoted to said jaws at different distances from said axis, and means connected to said supporting links to cause said jaws to open and close.

2. A grab, comprising, in combination, a pair of hinged jaws, supporting means therefor including long and short links pivoted to said jaws, respectively, and pivoted to each other to turn about an axis nearer to the pivotal connection of one link with its associated jaw than the pivotal connection of the other link with its associated jaw, a holding rope attached to said long link, and closing means including a closing lever, and a closing rope connecting said closing lever to said lon link.

3. A gra comprising, in combination, a pair of jaws hinged to turn about an axis, supporting means therefor including links pivotally connected to said jaws and pivoted toeach other to turn about an axis, said axes being disposed at opposite sides, respectively, of the vertical median line of the grab, and means connected to said supporting means to cause said jaws to open and close.

4. A grab comprising, in combination, a pair of hinged jaws, supporting means therefor including a frame pivoted toone of said jaws, a holding cable supporting said frame, and a link pivoted to the other of said jaws, said frame and link being pivoted to each other to turn about an axis offset from the vertical median'line of the grab, and means to cause said jaws to open and close, and including a sheave supported by said frame, a closing lever, a sheave supported by said closing lever, and a cable extending over said sheaves. v

5. A grab comprising, in combination, a pair of hinged jaws, supporting means therefor including a frame pivoted to one of said jaws, a holding cable supporting said frame, and a link pivoted to the other of said jaws, said frame and link being pivoted to each other to turn about an axis offset from the vertical median line of the grab, and means to cause said jaws to open and close and to press against each other when closed, and including a sheave mountedon said frame, a sheave carried by one of said jaws, and a cable extending over said sheaves and connected to said frame.

6 grab comprising, in combination, a pair of. hinged-j afws', supporting means therefor including a frame pivoted to one of said jaws, and a: link pivoted to the other of said jaws,- said frameand'link beingpivoted. to each otherto turn about an axis offset from thew' ertical median line of the grab, and 111621118 to cause said :jaws to open and close and to pressagainst each other when closed, and including sheaves mounted on. said frame, a sheave carried by one of sa'id'j'a-ws, and a cable passing over saidsheaves.

4. A grab bucket, comprising in combination, a pair of scoops hinged to turn about an axis laterallyoffset from the vertical median line of the grab, an arm carried by one of said scoops, supporting means pivotally connected to said scoops, a supporting cable attached to said supporting means, and an opening and closing cable connecting said arm to said supporting means. i

8. A grab bucket, comprising in combination, a pair of scoops hinged to turn about an axis laterally offset from the vertical median line of the grab, an arm carried by one of said scoops, supporting means including links pivotallyconnected to said scoops, respectively and pivoted together to swing about an axis laterally offset-from said line,

a supporting cable-attached to said supporting means, and an opening'and closing cable connecting said arm to said supporting,

means.

9. A grab comprislng, in comblnation, a pair of hlnged aws, supporting means therefor, a supporting cable attached to said I supporting means, a closing arm carried by one of said jaws, sheave wheels carried by said supporting means and said closing arm, a closing rope extending over said sheave wheels, and means for dead-ending said closing cable. on said supporting means or on said closing lever. a

10. A grab comprising, in combination, a pair of hinged jaws, supporting means therefor, a supporting cable attached to said supporting means, a closing arm carried by' one of said jaws, sheave wheels carried by said supporting means and said closing arm, a closing cable extending over saidsheave wheels, and closing cable clamps on said supporting means and on said closing lever.

11. A grab comprising, in combination, a pair of hinged jaws, supporting means therefor, a supporting cable attached to said supporting means, a closingarm carried by one of said jaws, sheave wheels carried bysaid supporting means and said closing arm, a closing cable extending over said sheave wheels, means to which said closing cable is dead-ended, and a guide carried by said closing arm against which guide said closing cable bends as said arm swings to and fro accompanying opemng and closingmovement of said jaws.

12; Agrab comprising, in combination, a pair of hinged jaws,supporting means there for, a supporting cable attached to said supporting means, a closing arm carried by one of said jaws, sheave wheels carried by said supporting means and said closing arm, a closing cable extending over said sheave wheels, means to which said closing cable is dead-ended, and a curved guide carried by said closing arm against which guide said closing cable bendsas said arm swings to and fro accompanying opening and closing movement of said jaws.

13. A grab comprising, in combination, a pair of hinged jaws, supporting means therefor, a supporting cable attached to said supporting means, a closing arm carried by one.

Wheels, clamps to which said closing cable is dead-ended, and a guide carried by said closing arm against whichguide said closing cable bends as said arm swings to and fro accompanying opening and closing movement of said jaws.

In testimony whereof, I have signed my name to this Specification. 1

ALMON E. onms.

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