US2587217A - Lifting device - Google Patents

Description

J. M. QUENAN LIFTING DEVICE Feb. 26, 1952 5 Sheets--SheefI 2 Filed March 18, 1949 Feb. 26, 1952 J. M. QUENAN 2,587,217

L11-"Tmc DEVICE Filed March 18, 1949 3 Smeets-Shea?l 3 7\ Wil iw I mi g v 37 i ili Il! 45 JNVENTOR.

3 65 CfyZ/Muewz Patented Feb. 26, 1952 UNITED STATES PATENT OFFICE LIFTING DEVICE Joseph M. Quenan, North Hornell, N. Y.

Application March 18, 1949, Serial No. 82,193

1 This invention relates to a lifting device, and particularly to one intended especially for the ,grasping and lifting of rocks or large stones,

such as when loading or unloading stones onto or from a. truck, railroad car, or barge, or when placing stones in given positions, such as when constructing riprap or a dike or a breakwater.

An object of the invention is the provision of a generally improved and more satisfactory lifting device of this character.

Another object is the provision of a lifting device so designed and constructed that articles of irregular shape, such as stones or rocks, will in almost every instance be grasped firmly, rigidly, and safely.

Still another object is the provision of such a lifting device so designed and constructed that stones or other articles lifted by the device will not become wedged in the device or cause any cloggingof it.

A further object is the provision of a lifting device having the characteristics above mentioned, particularly designed and adapted for easy operation by a power hoist or derrick.

A still further object is the provision of a lifting device which, while especially suitable for handling rocks or stones, may also be used eiiiciently for handling large logs in a safev manner.

These and other desirable objects are accomplished by the construction disclosed -as an illus- .trative embodiment of the invention in the following description and in the accompanying drawings forming a part hereof, in which:

Fig. 1 is aside elevation of a device in accordance with a preferred embodiment of the invention, viewed from one direction, with the grasp-v ing fingers in closed position;

Fig. 2 is a similar view of the device viewed from a different direction at right angles to the direction of viewing in Fig. 1;

Fig. 3 is a view similar to Fig. 2 but with the grasping lingers shown in fully open position;

Fig. 4 is a section taken substantially on the line 4 4 of Fig. 3;

Fig. 5 is an approximately horizontal section taken substantially on the line 5-5 of Fig. 3;

Fig. 6 is a view of the device partly in side elevation and partly in vertical section, viewed from the vopposite side from that shown in Fig.

1, and with the grasping fingers in open position;

Fig. 7 is a fragmentary vertical section taken substantially on the line 7 1 of Fig. 3;

Fig. '8 is a fragmentary horizontal section taken substantially on the line 8-8 of Fig. 3; and

Fig. 9 is a side elevation, with parts in section, Y

5 claims. (o1. 294-111) 2 of an individual one of the grasping fingers, showing also the removable caulks 0r spikes which may be used for more effectively handling logs.

The same reference numerals throughout the several views indicate the same parts.

Many attempts have been made in the past to provide mechanical lifting or grasping devices Y for handling large stones, but so far as is known at present, none of the prior constructions has proven wholly satisfactory. The prior devices have in some instances employed a series of fingers movable toward each other in converging paths, somewhat like the motion of the points of the blades of an orange peel bucket. In other instances, there have been two series of fingers movable toward each other in substantial parallelism, each series including two or more ngers. But these prior constructions have had the disadvantages, among others, that when the fingers converge toward each other, the rocks are very likely to become wedged between the fingers in such a way as to create a high degree of friction, preventing the fingers from opening properly when it is desired to disengage the rocks; land when two or more fingers have been used to engage each of the opposite sides of the rock, it has frequently happened that, due to the irregular shape of the rock, the rock would be grasped by only two fingers, one on each side, and

,would be held very precariously and insecurely,

with great danger of shifting its position and possibly dropping from the lifting or grasping device.

As distinguished from these prior constructions, the present lifting or grasping device provides three and only three grasping iingers, two of the fingers being iixedly secured to each other and adapted to engage the rock at two spaced points on one side of the rock, while the third finger engages the opposite side of the rock in a position approximately opposite the mid point between the two fingers rst mentioned. From this it follows that the rock, in spite of its irregular shape, is firmly and rigidly grasped with What may be termed a three-point suspension, and is held so that the rock cannot oscillate or shift in the grasping device. The same device is found to be highly effective also on logs, and will hold logs firmly due to the three-point contact therewith, notwithstanding substantial variations in the shapes of the logs, caused by large knots, the stub ends of limbs, or other irregular formations.

Referringnow to the drawings, the present device in its preferred form includes three massive and sturdy members of somewhat hookshaped form, each of the members including an article engaging finger portion elongated in one direction, and an operating lever or control lever portion elongated in another direction approximately at right angles to the direction of the nger portion. For example, the rst member includes the article engaging finger portion or jaw portion l I, and its operating or control lever portion I2. The other two members have article engaging nger portions or jaw portions I3 and I for engaging the opposite side of the rock or log or other article to be lifted, these nger portions being respectively provided with operating or control lever portions I4 and I6. The two finger portions I3 and I5 are laterally spaced from each other as seen in Figs. 5 and 6, and are rigidly connected to each other by a strong cross bar or web I9, preferably widened angularly at its ends, as indicated at 2i, for greater strength. The ends of the hook-shaped members which constitute the fingers II, I3, and I5 may conveniently be referred to as the outer ends of such members. The opposite or inner ends of these members are provided with eyes, constituting bearings, and a pivot pin extends through the eyes or bearings of all three of the operating arms I2, I4, and I5, thus joining or hinging all three of them together. Spacing members 21 (Fig. 5) may be placed on the pivot between the arms if desired.

The operating arm I2 of the first iinger may be substantially straight as seen in Fig. 5, while the operating arms I4 and I6 of the other two fingers are preferably oiiset toward each other, so that the eyes of these arms lieclosely adjacent the arm I2, as well seen in Fig. 5. As seen also in Figs. l and 6, but especially in Fig. 5, the arm I2 and its nger II swing in a plane approximately midway between the fingers I3 and I5. Consequently, when the fingers are swung relative to each other from the open position shown in Fig. 3 toward the closed position shown in- Fig. 2, there will be a three-point contact with any large article (such as a large stone or a log) linterposed between these fingers, two of the fingers I3 and I5 engaging the article at laterally spaced points on one side of the article, while the other iinger II engages the opposite side of the article at a point between the two spaced points engaged by the fingers I3 and I5. This three-point support insures a firm holding of the article, regardless of irregularities in its shape.

For controlling the opening and closing movements of the three hook members, an operating arrangement is employed which is somewhat similar to that used on a conventional clam shell bucket. Near the top of the appliance, a hollow somewhat bell shaped metal housing indicated in general at 3l and constituting a rigid hoisting head unit has openings for receiving a pair of pivot pins 33 and 35 supported from the strong walls of the housing. An operating link 31 has an eye at its upper end which encircies the pin 33, and at its lower end it has an eye encircling a pivot pin 39 which extends through the rst hook member in the general vicinity of the angle or shoulder between the finger portion I I and the operating lever portion l2, as well seen in Fig. 3. To give the structure greater rigidity against twisting forces, the lower end of the link 31, in the vicinity of the pivot pin 39, is preferably bifurcated or longitudinally split and laterally separated into two parts so as to straddle the member II, I2 (as well seen in Fig. 1), while the upper end of the link 31 is similarly longitudinally split and laterally separated to give it a greater length of bearing on the pivot pin 33, the forked ends having a spacer bushing 4I between them as seen in Fig. 4. Rigidity against lateral sway of the single inger member II-I2 is also enhanced by using bracing straps 42 (Fig. 5) each welded at one end to the member I2, the other ends being laterally separated and encircling the pivot pin 25. The bracing straps are well shown in Fig. 5 but are omitted from the other figures for the sake of clarity.

On the other. pivot pin 35 of the housing 3l, two operating links 43 and 45 are pivoted at their upper ends. The lower ends of both of these links are split or bifurcated, so as to straddle the members I3, I4, and I5, I6, respectively, and the eyes at the lower end of the link 43 are connected by a pivot. pin 41 to the angle or shoulder portion of the member I3, I4, while the eyes at the lower end of the other link are similarly connected by a pivot pin 49 to the angle or shoulder portion of the member I5, I6, as well seen in Fig. 6. Each of the links 43 and 45 is oiset laterally intermediate its ends, so that the upper ends of these links may be approximately in contact or at least closely adjacent to each other, while the lower ends are laterally separated to a substantial distance corresponding to the lateral separation between the members I3 and I5.

A clevis 5I straddles the casing 3I and has eyes which encircle the pivot pin 35. To this clevis 5I is attached the main hoisting line or cable 53 which hoists the appliance as a whole.

A third pivot pin 51 extends through the housing 3|, preferably at an elevation a little below the pivot pins 33 and 35 and approximately midway between them, as seen in Fig. 3. This pivot pin 51 forms a bearing for a pair of sheaves or pulleys 59 (Fig. '1) mounted on the pivot pin, with suitable spacers such as the bushings 6I.

On the lower central pivot 25 there is mounted. in addition to the members I2, I4, and I6, a pulley block including strap or clevis members 21 and 65 encircling the pivot 25 at their lower ends, and supporting a pivot pin 61 (Figs. 3 and 8) and a protective housing 69, open at the top and closed at the sides and bottom. Within the housing, mountedV on the pivot pin 61, are a pair of sheaves or pulleys 1I. At the top of the clevis 65 is a suitable cable attaching member, such as the eye 13. I i

The operating line 15 (such as a steel cable) has its end secured to the eye 13 as seen in Fig. 3. Thence the line extends upwardly over one of the upper sheaves 59, then down to one of the lower sheaves 1I, thence upwardly again to the second one of the upper sheaves 59, thence downwardly again to the second one of the lower sheaves 1I, and thence upwardly past the upper sheaves and out through a hole in the top of the housing 3l. In order that the line may run true on both sets of sheaves, the clevis 65 is twisted or skewed between the pivot 25 and the pivot 61, as seen in Figs. 3 and 8, to the extent necessary to make the respective grooves of the upper sheaves 59 which respectively receive the same reaches or stretches of the cable 15.

As will be readily understood by those familiar with the operation of clam shell buckets, the two lines or cables 53 and 15 are connected to two separate hoisting drums of the winch of the hoist or derrick which is used with this appliance. An upward pull on the line 53 will lift the present appliance as a whole. An upward pull on the line 15 will tend to pull the lower sheave pivot B1 upwardly toward the upper sheave pivot 51, thus tending to close the jaws from the open position shown in Fig. 3 to the closed position shown in Fig. 2. If the line 15 be slackened while maintaining tension on the line 53, then the weight of the parts will cause the pivots 25, 61 to move downwardly, opening up the jaws again from the closed position to the open position of Fig. 3.

Because of the fact that the single jaw or finger on one side of the appliance is not directly opposite any jaw or finger on the other side, but is intermediate between the two spaced jaws on the other side, it follows that the jaws do not interferewith each other, and the appliance may be closed to a point where, when viewed in side elevation as in Fig. 2, the jaw on one side 'slightly overlaps the jaws on the other side. This insures complete closing of the jaws as may be necessary under some circumstances for handling articles considerably smaller than the maximum size articles for which the particular appliance is designed.

To enable somewhat better gripping of rocks or other articles of a variety of sizes, the article v engaging faces of the fingers Il, i3, and I5 are formed of a generally convex shape. This convex shape helps to produce a firm bearing on articles which are engaged near the tip ends of the fingers and assists in producing lateral pressure, as distinguished from upward pressure, on articles engaged by the jaws or fingers when they are in a partly closed position. Moreover, articles of differ-ent sizes will be engaged at different points on the convex working surfaces of the jaw fingers, thus distributing the wearing or grinding action caused by the rocks, and lengthening the life of the appliance as compared with one in which rocks of various sizes are usually engaged by only the tip ends of the grasping fingers. On these convex work-engaging surfaces, the fingers II, I3, and I5 are preferably provided with strong and rugged serrations or projections,

conveniently in the form of ridges or ribs of trii angular cross section integrally formed on the linger members and extending crosswise of them: that is, in directions parallel to the pivots 25, 39, 41, and 49. Such an arrangement is found in actual practice to result in extremely effective Y and satisfactory handling of stones.

Logs may also be handled by the fingers constructed in this mann-er, but to increase the efciency of handling logs, it is preferred to provide each of these fingers I I, I3, and I5 with a series of holes 85 (Fig. 9) bored completely through the fingers approximately perpendicular to the working faces of the fingers, in the spaces between the ridges or ribs 8i. Sharp pointed caulks or spikes 81, having heads which will not go through the holes and Shanks which fit snugly in the holes, may be set in the holes with the pointed heads projecting into position for engaging logs or the like. When it is desired to resume the handling of stones, the caulks are removed from the fingers, and if they are stuck therein, they may be easily driven out by the use of a drift pin inserted in the holes 85 to the rear of the shanks of the caulks.

It may be noted that the length of the operating arms of each nger, between the pivot 25 and the pivot 39, for example, is materially greater (preferably approximately twice as great) as the length of the finger from the pivot point 39 to the approximate point on the finger which .engages with' the article to be handled. This produces a substantial mechanical advantage or leverage which aids in firmly and safely grasping heavy articles such as rocks.

Also it may be noted that-the relatively long lever arms or operating levers- I2, I4. and I6 enable the grasping fingers or jaws II, I3, and I5 to be opened up to a comparatively wide free or clear space between them, for handling comparatively' large articles. Moreover, it is seen that when the grasping fingers or jaws are opened up to a slightly lesser extent than shown in Fig. 3 (that is, with the central pivot 25 a little higher than shown in Fig. 3) the space between the grasping fingers is completely clear and unobstructed in a direction perpendicular `to the plane of the paper of Fig. 3, so there is nothing to interfere with the article which is to be handled extending lengthwise (perpendicular to the paper) to any desired extent in either lor both directions from the handling or grasping device.

This characteristic enables the device to be readily used for handling long objects like logs, whereas in certain prior constructions intended for grasping stones on four or five sides at once, some of the stone grasping fingers would interfere with picking up logs. Furthermore, it is to be noted that the two fingers I3 and I5` are always in fixed position relative to each other, and the swinging of the grasping jaws or fingers is what may be termed a single plane swinging movement, with no oblique converging movement which might cause rocks or other articles to become wedged in the appliance.

The housing 59 helps to protect the lower sheaves 1I from dirt or debris. The various pivot pins above mentioned are preferably all removable, and are held in place by cotter pins or other removable fastening devices.

It is seen from the foregoing disclosure that the above-mentioned objects of the invention are admirably fulfilled. It is to be understood that the foregoing disclosure is given by way of illustrative example only, rather than by way of limitation, and that without departing from the invention, the details may be Varied within the scope of the appended claims.

What is claimed is:

l. A lifting device for handling articles of irregular shape such as rocks and stones embodying a rigid, unitary, hoisting head, a pair of opposed grab hooks, each formed of an upper shank portion and a relatively abruptly angular finger portion that is adapted to engage beneath and actively support the object actedI upon against a lifting strain, one such finger portion consisting solely of a pair of relatively spaced prongs and the other of a single prong alined with the space between the said pair of prongs, a pivot connecting the shank portions from which the finger portions may swing toward and from each other, a pulley block supporting said pivot, a pair of relatively spaced fixed pivots on the hoisting head, a plurality of control links depending from said last mentioned pivots, respectively, and pivotally connected at their respective lower ends to the respective grab hooks at the junction of their shank portions and their prongs, a fixed pulley on the hoisting head, means on the latter for attaching the free end of a flexible hoisting line, and means on the first mentioned pulley block for attaching the terminal of a flexible control line running over both pulleys.

2. A lifting device in accordance with claim 1,

7 in which the pulley on the hoisting head is located between the pivots .on the latter that supportl the control links andthe rigid head is provided with an opening for passage therethrough of the control line.

3. A lifting device in accordance with claim 1. in which the shank portion of the hook having the pair of nger prongs is divided into two parts engaging the iirst mentioned pvot on opposite sides of the shank of the hook having the single finger prong.

4. A lifting device in accordance with claim 3, in which the pair of nger prongs on one hook are connected by a rigid web.

5. A lifting device for handling articles of irregular shape such as rocks and stones embodying a rigid, unitary hoisting head, a pair of opposed grab hooks, each composed of an upper shank portion and a relatively abruptly angular finger portion that is adapted to engage beneath and actively support against a lifting strain, one such finger portion consisting solely of a pair of relatively spaced prongs and the other of a single prong alined with the space between the said pair of prongs, a pivot connecting the shank portions from which the finger portions may swing toward and from each other, a pulley block supporting said pivot, a plurality of control links pivoted to the hoisting head at their upper ends and pivotally connected at their respective lower ends to the respective grab hooks at the junction of their shank portions and their finger prongs, a xed pulley on the hoisting head, means 'on the latter for attaching the free end of a flexible hoisting line, and means on the rst mentioned pulley block for attaching the terminal of a flexible control line running over both pulleys.

JOSEPH M. QUENAN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,191,660 Butler July 18, 1916 1,563,255 Couch Nov. 24, 1925 1,587,479 Durocher June 1, 1926 1,988,135 Odman Jan. 15, 1935 2,362,268 Hall Nov. 7, 1944 FOREIGN PATENTS Number Country Date 277,200 Germany July 30, 1914

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