US1129356A - Rock-grab. - Google Patents

Description

INVENTOR I Patented Feb. 23, 1915.

J. MADILL.

ROCK GRAB APPLICATION FILED mmzs, 1914,

M w M WITNESSES:

7m NORRIS PE TERS C0,, PHOTG-LITHQ, WASHINGTON. D

JOHN avian-ILL, or rear anrnnn, on'ranxo, cannon.

' ROCK-GRAB.

specification of Letters Patent. Patented Feb. 23, 1915.

Application filed March 23, 1914. Serial No. 826,830,

To all whom it may concern:

Be it known that l, Jenn MADILL, a citizen of the Dominion of Canada, residing at Port Arthur, inthe Province of Ontario, Dominion of Canada, have invented a new and lmproved RocleG-rab, of which the following is a specification.

This invention, which generally relates to means for loading and unloading, more particularly has reference to grapples, clam shell buckets and other like means in which the grab or grappling devices are arranged for being raised and lowered by suitable hoisting mechanism.

1My invention primarily has for its purpose to provide an appliance or means that is more particularly designed for handling large rock and boulders for public Works, break waters, etc, and in which the grappling elements may be readily formed with quarter shells or Wings to adapt the said appliance or means for digging and hoisting such filling as sand, mud, gravel and shale rock.

Another and essential object of my vention is to provide a grapple of the general type stated, in which the grappling hooks or members are cooperatively so mounted upon a single head block whereby to provide for the utilization of a simple and effective device for equalizing the strain upon the grappling hooks, and whereby the said grapples are caused to conform to any irregular objects.

Another object of my invention is to provide a rock grab whose parts are so designed ,to operate under asimple actuating mechanism, and so that all are protectedas far as possible from injury or from becoming easily disabled under ordinary uses and joined in such a manner that any part may be quickly removed and replaced.

With other objects'in view, all of which will be hereinafter explained, my invention is an improved rock grab that embodies the peculiar features of construction and combination of parts, all of which will be hereinafter first described, specifically pointed out in the appended claims, and illustrated in the accompanying drawing, in which:

Figure 1 is a perspective view of my improved rock grab, the same being shown at its opened position. Fig. 2 is a top plan view thereof, the grapple members or hooks being shown at their closed or grabbing position. Fig. 3 is a vertical section of the same taken on the line 33 on Fig. 2. Fig. 4 is a sectionalelevation of the equalizing block hereinafter referred to, showing the chain connection to the various grippers, diagrammatically. Fig. 5 is a diagram matic perspective view showing how the grippers adapt themselves to objects of irregular contour.

In the practical construction, my invention includes a single or head block casting 1.,formedwith a central circular aperture 10, and four regularly equally spaced bifurcated extensions arranged in opposite pairs, designated 11-11, 12-l2, respectively, and

each is provided with a transverse bearing for receiving the pivot bolts 13-13 upon each of which is pivotally hung the head end 20 of a grab or hook member 2 and having the usual shape, as shown.

14tdesignates the nutsthat engage the bolts 13.

Each grab member or hook 2, at a point near its pivoted head is formed with a bifurcated inwardly extending bracket 21 within which is located a chain guide wheel 23, mounted upon the stud pins 4: transversely mounted in the said brackets and which receive the nuts 4:0, as shown.

By suspending the grab hooks independently, from the head block 1, as shown and described, allows the said grab hooks to each work independently, and to hold them from spreading too far apart, they are joined by four safety stay chains 6 whose ends are attached to keepers 7, one of which is pivotally mounted on each hook.

For distributing an equal closing strain on the four hooks collectively, though they work independently of each other, I use a closing chain that consists of two bights or sections designated 8-80, and each of which is in the nature of a pendent loop, the upper or free end of one of which, is connected to one end of a heavy equalizing chain 9 that is suspended looplike from a pulley block 22, mounted in a bracket 23 hung on a clevis-like hanger 24: that joins with the lower end ofthe hoist ing cable 25. The other end of the equalizing chain 9 connects with the free ends 81 of the closing chain section 80. It will be noticed the two chain sections 80 and 8 cross each other'where they pass over from one set of chain guide wheels 33 and the four strands of the said chain sections 80-8 pass up through the central opening in the head block and over guide rollers 15 journaled on the bolts 16 in the bracket-like cars 17 cast with the head block, the several rollers 15 being so positioned, relatively to the edge of the said opening, to project suliiciently to keep the chains from rubbing up against the said edge.

When an object of irregular contour is grabbed as shown in Fig. 5, the hooks will adapt themselves closely to the uneven surface since the closing chain sections 8 and 80 may draw the hooks together until the hooks have set themselves after which the chain sections 8 and 80 will be equalized through the medium of the chain section 9 passing over the sheave 22.

18 designates the tripping cable, the lower end of which carries a heavy ring 19 with which the several. lift chains 26, one for each grapple or hook member to which the chains connect, as shown.

Each hook or grapple member has a stop lug 27 at the head end that forms a stop for engaging the head block and holding the hooks from being swung up too high.

From the foregoing taken in connection with the drawing, the complete construction and the manner of use of my invention will be readily understood.

It will be readily seen the grapples being at their. opened position, when lowered and power. is applied to the closing chains, there is a powerful pull on the two opposing sets of grapples or hooks and cause them to close in under the rock or other material to be raised, andwhen the load is grabbed, the hoisting cable elevates the grab with the load and swings'it to thedumping or unloading point, and the said load discharged by pulling on'the trip cables or, chains, and at the same time slackening the closing chains.

I While I have not shown it, it is obvious that the end of the grapples may be fitted with winged blades to adapt them to act as scoops for digging and lifting soft ma- 'terial.

WVhat I claim is:

1. In a grab of the character described, a single head block, two pairs of oppositely set grappling hooks, each of said hooks being independently hung on the head block,

a closing cable for each pair of hooks, an

equalizing means to which the free ends of the said chains connect, a hoisting cable connected to the said means and other means for'tripping the grappling hooks to swing Copies of this patent may be obtained for them to their open position as tension 011 the closing cables is released.

2. In a grab of the character stated, a head block, a plurality of grappling hooks pivotally connected at their upper ends to said head block, stay connections between the several hooks below the pivots, a trip line flexibly connected with the respective hooks whereby to sustain the said hooks to their open position, a hoisting line, an equalizing block carried by said hoisting line, and closing cables connected with the respective hooks and with said equalizing block.

3. In a device of the character stated, a head block, a plurality of sets of grapples pivotally connected at their upper ends to said head block, stops limiting the opening movement of said grapples, flexible spacing members connecting said grapples with each other, a trip cable, separate connections between said cable and the respective grapples whereby to open up said grapples when the apparatus is suspended by said cable, an equalizing block carried by said hoisting cable, a closing cable passing through said block and having endless loops one for each pair of grapples, members carried by said grapples and projecting into said loops whereby when the apparatus is supported by said hoisting cable the tension on said closing cable will draw said grapples together, substantially as shown and described.

1. In a device of the character stated, a head block, a plurality of sets of grapples pivotally connected at their upper ends to said head block, stops limiting the opening movement of said grapples, flexible spacing members connecting said grapples with each other, a trip cable, separate connections between said cable and the respective grapples whereby to open up said grapples when the apparatus is suspended by said cable, an equalizing block carried by said hoisting cable, a closing cable passing through said block and having endless loops one for each pair of grapples, members carried by said grapples and projecting into said loops whereby when the apparatus is supported by said hoisting cable the tension on said closing cable will draw said grapples together, and guide rollers on said head block over which said closing cable passes.

JOHN MADILL. 1. s.] Witnesses:

W. E. MUTCH, A. B. BARBER.

five cents each, by addressing the Commissioner of Patents Washington, D. G.

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