US3248145A - Beam lifting hook - Google Patents

Description

April 26, 1966 l. DIAMOND 3,248,145

BEAM LIFTING HOOK Filed July s1. 196s s sheets-sheet 1 19o S/wgal/w' WL Shalw las Ime ATT RNEY5 April 26, 1966 l. DIAMOND BEAM LIFTING HOOK 3 Sheets-Sheet 2 Filed July 3l, 1963 IRVING DIAMOND afl/w' maf ATTORNEYS April 26, 1966 l. DIAMoND 3,248,145

BEAM |IF"'.|1:|:|G HOOK Filed July 31, 1963 s sheets-sheet s O mw |NVENTOR.

lRVlNG DIAMOND FIG."

cedure is inconvenient and dangerous.

United States Patent O 3,248,145 BEAM LIFTING HOOK Irving Diamond, Hillside, NJ. (P.0. Box 360, Elizabeth, NJ.) Filed July 31, 1963, Ser. No. 298,956 18 Claims. (Cl. 294-86) This invention relates to lifting devices and, more particularly, to devices for hoisting structural beams such as I-beams.

At the present time, it is customary to hoist structural steel members by first tying a steel ycable around the member and then attaching this cable to a hoist line. It has been found, however, that this conventional pro- It is often Vnecessary, for example, to shore the beam before tying the cable thereabout. Since it is ditlicult to maintain the beam in a true upright and horizontal position, it is not easily fitted for bolting to the structure being erected. After the beam is lifted and placed' in position, it is necessary for a workman to climb on the beam to disengage the line and remove the cable. Moreover, the cables are subject to nicks and fractures and frequently become unsafe to use.

Although a number of devices for grappling objects to be hoisted have been proposed, these devices have a number of drawbacks and have not been generally accepted by the steel erection industry. One prior art device, for example, is unduly complicated in that it requires an electric motor and a complex linkage for opening and closing the grappling jaws. Another prior art device, which is specially designed for hoisting structural beams and which employs pivoted hook arms for engaging the ange of such beams, is inconvenient to use in that it is still necessary to manually disengage the hook arms from the beam after the beam has been placed in position.

Other prior art lifting devices which are designed to oper-V ate automatically require complicated locking mechanisms to hold them in the open position. Although a simplified lock in the form of a pair of toggle links has been proposed in a further prior art device, these links are located adjacent the lower ends of pivoted grappling arms and are exposed andsubject to accidental unlocking. It is accordingly the principal object of this invention to provide an improved lifting device for grappling objects to be hoisted.

Another object of the invention'is the provision of a beam lifting hook which will automatically open when the beam is deposited in its desired location and which will remain open when the beam lifting hook is moved to engage yan additional beam to be hoisted.

Still another object of the invention is the provision of improved locking means for retaining the beam lifting hook in the open position., A related object is the the beam lifting device of the invention to be unlocked whereby it may be closed upon an additional beam to be hoisted.

An additional object is the provision of a beam lifting hook operating on the principle of lazy' tongs which will close in response to tension in the hoist line and will open in response to slack in the line. Since it is necessary to avoid opening such a beam lifting hook in response to accidental slack in the hoist line, as when a beam momentarily bumps into an obstacle, a further object of the invention is the provision of lost motion means for delaying opening of the beam lifting hook until the slack in the hoist line exceeds a predetermined minimum.

Yet another object of the invention is the provision of a beam lifting device having grappling hooks guided for reciprocation in a horizontal plane with a constant attitude of engagement with the ange of a beam to be Patented Apr. 26, 1966 Other objects include the provision of a beam lifting i device having adjustable guide means for centering the device on a beam to be hoisted and a at lower bearing surface for seating the device squarely onA the flange of a beam, the provision of a rugged and durable beam lifting device having a rigid frame, and the provision of a beam lifting device which is convenient and safe to use and which will readily maintain a beam in a true upright and horizontal position as it is hoisted.

Briefly, but without limitation, the invention contemplates the use of a lazy tongs arrangement of upper arms pivoted to a mounting yoke and lower arms eX- tending beyond a point of intersection. The lower ends of the lower arms are coupled respectively to oppositely directed grappling hooks which are guided for reciprocation in a horizontal plane upon movement of the lower arms. Tension in the hoist line causes the lazy tongs arrangement to elongate, moving the lower end of the lower arms toward each other to reciprocate the hooks into engagement with the flange of a beam to be hoisted. On the other hand, slack in the hoist line causes the lazy tongs arrangement to collapse, separating the lower ends of the lower arms to reciprocate the hooks out of engagement with the beam flange to release the beam.

-A toggle lock, comprising a pair of hinged toggle links, is

coupled between corresponding points on the lower arms above the point of intersection and serves to lock the lazy tongs in its collapsed position by virtue of a1ignment of the toggle links. -A handle is provided on each of the toggle links to enable a workman to raise the hinge point of the toggle links to unlock the lazy tongs until tension in the hoist line causes the lazy tongs arrangement to elongate, bringing the hooks into engagement with the ange of a beam to be hoisted. In order to avoid accidental opening of the lifting device due to momentary loss of tension in the hoist line, a lost motion device is provided between the mounting yoke and the hoist line. Adjustable guide iingers are provided to facilitate centering the device on a beam to be hoisted, and the device presents a ilat lower bearing surface between'the grappling hooks so that it may be seated squarely on the flange of a beam to be hoisted.

The foregoing and other objects, advantageous, and features of the invention and the manner in which the same are accomplished will become more readily apparent upon consideration of the following detailed description of the inventiontaken in conjunction with the accompanying drawings, which illustrate a preferred and exemplary embodiment, and wherein:

FIGURE l is a front elevation view of a device of the invention in a closed position;

FIGURE 2 is a side elevation View of the device, positioned as in FIGURE 1, as seen from the right;

FIGURE 3 is a front elevation view of a device of the invention in its collapsed, or open, position;l

FIGURE 4 is a fragmentary side elevation view, partly in section, showing the mounting yoke of the device of the invention;

FIGURE 5 is a perspective view, partially exploded, showing a portion of the device of the invention; FIGURE 6 is a front elevation view of the device of the invention closed on the flange of an I-beam;

FIGURE 7 is a bottom view of a device of the invention, positioned as in FIGURE 6, with the I-beam removed;

FIGURE 8 is a section view taken along the lines 8 8 of FIGURE 1;

FIGURE 9 is a section view taken along the lines 9 9 of FIGURE -1 FIGURE is a section view taken along the lines 10-10 of FIGURE 1;

FIGURE 11 is a section view taken along the lines 11-11of FIGURE l;

FIGURE 12 is a section view taken along the lines 12-12 of FIGURE l;

FIGURE 13 is .a section view taken along the lines 13-13 of FIGURE l; and

FIGURE 14 is .a section view .taken lalong the lines 14-14 of FIGURE 1.

Turning now to the drawings, it will be seen that a beam lifting -hook of the invention gener-ally comprises a mounting yoke by means of which the device is suspended from a hoist line (not shown), a lazy tongs arrangement 22 which, as will be presently described, serves as the actuating mechanism of the device, a lock assembly 24, and a lower frame -assembly 26 which includes a Set of .beam ilange engaging, or grappling, hooks 28 which are coupled by means to be described hereinbelow to the lower extremities of the lazy tongs arrangement. Tension in the hoist line causes the lazy tongs arrangement 22 'to elongate, moving its llower extremities toward each other as shown in FIGURE 6 to close the set of grapple hooks 28 on the beam 270 to .be hoisted. When the hoist :line becomes slack, as when the-beam Vis set down in a desired location, the lazy tongs arrangement22 collapses 4as shown in FIGURE 3, bringing .the lower extremi-ties of the lazy t-ongs .arrangement 22 apart and `separating the set of grappling hooks 28 to open the device. The lock -assembly 24 then serves to maintain the lazy tongs arrangement 22 in its collapsed position so that the device may -be moved, without closing, to another -beam which is to be hoisted.

Since momentary slack in the hoist line caused by accidental bumping of the device or ybeam against an obstacle could cause the lazy Itongs arrangement 22 to collapse, the mounting yoke 20 includes lost motion means to delay collapse of the lazy tongs arrangement 22 until `the slack in the hoist line exceeds a predetermined minimum. As will be best rseen from FIGURE 4, the mounting yoke 20 comprises a cylindrical housing 30 which is :partially closed by abutment means 32 at its upper end and open at i-ts bottom' end 34. vA mounting bolt 36 extends through the upper end 32 of housing `30 to the lower end 34 of the housing, and a nu-t 38 and washer 40 threaded `on the lower end of bolt 36 serve as an abut-y :ment member for a coil compression spring 42 which is retained within the cylindrical housing between the Washer and the abutment means 32 at the upper end of the housing. In order to suspend the device from a hoist line, the upper end` of mounting bolt 36 is provided with an -eye 44 which may be secured to the hoist line by any suitable means, such as a mounting hook attached to the line. It will be evident from the above that tension in the hoist line will cause mounting bolt 36 to move upwardly in cylindrical housing 30, as shown in FIGURE 6, causing the coil spring 42 to compress. Thus, momentary slack in the hoist line will not alect lazy tongs arrangement 22 until coil spring 42 returns to its normal, fully extended condition as shown in FIGURE 4.

The mounting yoke 20 also serves as a pivotal support for the upper end of lazy tongs arrangement 22. To

relationship fby means of a spacing strut comprising Iav Likewise, the

bolt 70 and a spacer sleeve (not shown). spaced, parallel upper arms 66 and 68, which are pivoted on trunnions 54 and 56, respectively, between arm 62 and boss 46 and arm I64 and boss 48, extend downwardly at an angle in the opposite direct-ion and are spaced apart by means of a spacing strut comprising a bolt 72 and a spacer sleeve 74 therearound. As will be evident from FIGUR-E 2, the threaded ends of bolts 70 and 72 receive nuts 76 and 78, respectively.

The lower ends of spaced, parallel upper arms 62 andV 64 are hinged to a pair of spaced, parallel lower arms 80 t.

and 82 'by means of a pivot bolt 84 which extends th-.rou-gh -upper arm 62, the upper end of lower arm 80, a spacerV sleeve 86 (see FIGURE 7), the upper end of lower arm 82, and the lower end of upper arm 64. Similarly, the lower ends of upper arms 66 and 68 are hinged to the upper ends of a pair of spaced, parallel lower arms 90 and 92 by means of a pivot bolt 94 which extends through the upper end of lower arm 90, the lower end of upper arm 66, a spacer sleeve 96, the lower end of upper arm` spacer sleeve 102 `which is supported 4by a spacer bolt 104 extending through arms 90 and 92 as shown .in FIGURE 2. The free end of spacer bolt 104 receives a retaining nut .106, and a similar nut (not shown) is threaded on the free end of bolt 100.

It will be observed that .the pair of lower arms 80, 82

intersect the pair of lower arms 90, 92 a-t a point d-irectly beneath trunnions 54, 56 and are interconnected at this this end, a pair of bosses 46 and 48 project from diametrij cally opposed points adjacent the lower end of cylindrical housing 30 and receive the .threaded ends 50 and 52 of a pair of trunnions 54 and 56 in aligned threaded openings. The distal ends of the trunn- ions 54 and 56 are provided, respectively, with nuts l58 and 60.

Trunnions -54 and 56 serve as a common pivot axis for the upper ends of two pairs of spaced, parallel upper arms 62, 64 and 66, 68 of lazy tongs arrangement 22. The first pair of spaced, parallel upper arms `62, 64, which extend downwardly at an angle in a lirst direction, are pivoted on trunnions 54 and 56, respectively, adjacent nuts 58 and 60, and are Vrigidly held in spaced, parallel point by a hinge ypin 108. As shown most clearly in FIG- -URES 2 and 5, =pin l108 extends through lower arm 90,`

lower arm 80, a slot 1,10 in a vertical guide plate '112, a spacer sleeve 114, a slot 116 in a vertical guide plate 118, lower arm 82, and lower arm 92. |108 =is shown as a centerline in FIGURE 5.) A- bolt head at one end of pivot pin 108 and la nut 122 at the other end of .this pin retain it in position. When the device is suspended from a hoist line, it has a vertical axis extending from eye 44, along mounting bolt 36, between trunnions 54 and 56, through pin 108, and between slots 110 and 1.16. It will be readily apparent from the above that the slots 110 and 116 of vertical guide plates 112 and 118 serve to guide hinge pin 108 along the vertical axis as `the lazy tongs arrangement 22 elongates and collapses.

As previously explained, the lock assembly 24 serves to hold the lazy tongs arrangement 22 in its collapsed` position so Athat .the lifting device of the invention may be moved in its4 open position to a beam to be hoisted. The look operates on the principle of a toggle and consists of a pair of toggle links 124 `and 126 which are coupled between corresponding points on the pairs of lower arms 80, 82 and 90, 92 above their point of intersect-ion. The .toggleV link 124 comprises a single arm hinged to the pair of lower arms 80, 82 by means of a pivot -pin 128 (shown as a center line in FIGURE 5) which extends through lower arm 80, a spacer sleeve (not shown), link arm 124, a spacer sleeve (not shown),

and lower arm 82. In order to retain pivot pin 128 in position, it is provided with a bolt head 130 at one end and a nut (not shown) at the other end. The toggle link 126 comprises a pair of spaced, parallel toggle arms 132 and 134 which are h-inged to lower arms 90, 92 .by means of a pivot pin 136 extending through'lower arm 90, a spacer sleeve 138, toggle link arm 132, spacer sleeve 140, toggle link arm 134, spacer sleeve 142, and lower arm (Note that hinge pin` 92. Pin 136 is retained in position by virtue of a bolt head 144 at one end and a nut 146 at the other end. The Itoggle links 124 and 126 are hinged together at their free ends by means of a hinge pin 148 which extends through toggle- link arms 132, 124, and 134 and is retained in position by a bolt head 150 at .one end and a nut 152 at the other end.

The locking action of the toggle links will be evident from a consideration of FIGURE 3. As lazy tongs arrangement 22 collapses, toggle links 124 and 126 are brought into alignment. Since the toggle will now be .at deadenter, it will lock lazy tongs arrangement 22 in its` collapsed position. The toggle links are prevented from going over-center, with the hinge pin 148 below center, by means of an abutment extension 154 provided at the hinge end of toggle link arm 124 and a stop pin 156 prorvided between parallel toggle link arms 132 and 134.

Thus, when the toggle links 124 and 126 are brought into Y alignment the abutment extension 154 abuts against stop pin 156 thereby preventing t-he hinge pin 148 from going below center.

In order to facilitate unlocking of the device, a pair of handles 158 and 160 are respectively provided on toggle links 124 and 126. As shown most clearly in FIGURE man grasps one of the handles 1-58, 160 and pushes up.

wardly to bring hinge pin 148 above center. lThe device is then unlocked and ready to close in response to ten- -sion in the hoist line.

It will be evident from the above that the lock assembly 24 is located in a protected posi-tion above the lower frame assembly 26. It iis thus unlikely to become subject to accidental unlocking by striking an obstacle which would force the hinge pin 148 above center.

The manner in which the lazy tongs arrangement 22 functions to actuate the s et of grappling hooks 28 will be understood from a consideration of the lower frame assembly 26. 'Ilhe .frame assembly 26 includes a pair of elongated clam- p plate 162 and 164 which are mounted in spaced parallel relationship on`a pair of -tie rods 166 and 168 (shown as center lines in FIGURE 5) which extend through holes adjacent the ends of the clam-p plates. The

tie rod 166 is maintained in position by means of a pair of nuts 170 and 172 at opposite ends thereof bearing on the outer surfaces of the clamp plates 162 and 164 respectively. Likewise, tie rod 168 is maintained in posi- .tion by means of a pair of nuts 174 and 176 which bear respectively on the outer surfaces of clamp pla- tes 162 and 164. Y

A plurality of hook plates 178, 180, 182 and 184 are maintained between and in parallel relation to the clamp plates 162 and 164. The rst hook plate 178 is pro vided with a longitudinally extending horizontal guide s-lot 186 and a hook-like projection 188 depending downwardly and rearwardly from one endto provide a ange engaging surface-190. The second hook plate 180 is also provided with a horizontal guide slot 192 extend-ing along the length thereof and has a hook-like projection 194 depending from the opposite end to form a flange engaging surface 196. In like manner, the third hook plate 1,82

has a horizontal guide slot 198 and a hook-like projection- 200 depending from the opposite end (see FIGURE 7) to form a flange engaging surface (not shown). The fourth hook plate, 184 is also characterized by a horizontal guide slot 202 and has a hook-like projection 204 depending from the first end (see FIGURE 7) to .presen-t a fourth ange engaging surface (not shown). It will be readily apparent that the upper and lower edges or surfaces of the aforementioned horizontal guide slots constitute guide surface means perpendicular to the vertcal axis of the device. It is to be understood that the hook projections 188, 194, 200 and 204 comprise the set of grappling hooks 28. Y

Referring to FIGURE 5, it will be seen that the vertical guide plates 112 and 118 are of `inverted T contiguration with respective cross arms 206 and 208 being laterally.

oset from the vertical stem portions of the plates. 'Ihe cross arms 206 and '208 are located between hook plates `180 and 182 and are mounted in spaced, parallel relationship on tie rods 166 and y168 which extend through holes adjacent the respective ends thereof.

It will be observed that tie rod 166 passes through slot 186 of hook plate 178 and slot 202 of hook .plate 184, while tie rod 168 passes through slots ,192 and 198 of hook plates 1.80 and 182, respectively. The tie rods thus serve to support the respective hook plates as they are reciprocated in a horizontal plane.

The means for effecting Ithis reciprocation .will now .be described. It will be observed that the lower end of lower arm 90 is located between the hook plates 178 and 180 adjacent to hook .plate 178 and is coupled to hook plate 180 by means of a pin 210 (shown as a center line in FIGURE 5) which extends into a hole 212 at the hook end of hook plate 180, through a spacer sleeve 214, through a hole 216 at the lower end of lower arm 90, and into slot 186. The clamp plate 162 and cross arm .206 reta-in pin 210 in position. In like manner, the lower end of lower arm lies between hook plates 178 and V180 adjacent plate 180 and is coupled to hook plate 178 by means of a coupling pin 218 (shown ,as a center line in FIGURE 5) which extends into a hole 220 at the hook end of hook plate 178, through a spacer sleeve 222, through a hole 224 at the lower end of lower arm 80, and

' into slot 192 of hook plate 180. The coupling pin 218 is held in position between clam-p plate 162 and cross arm 206. In a similar fashion, the lower end of lower arm 92 is retained between hook plates 182 and 184 adjacent plate 184 and is coupled to hook plate 182 by means of a coupling pin 226 (see FIGURE l0) one end of which is set in a hole 228 at the hook end of hook plate 182 and which extends through a spacer sleeve 230, a hole 232 near the lower end of lower arm 92, and into slot 202 of hook plate 184. The pin 226 is held in position between clamp plate 164 and cross arm 208. IIn the same manner, lower arm 82 is coupled to hook ,plate 184. Thus, a coupling pin 234, retained between clamp plate 164 and cross arm 208 (see FIGUR'E 12), extends from hole 236 at the hook end of hook plate 184, through a spacer sleeve 238, through a hole 240 at the lower end of lower arm 82, and into the horizontal guide slot 198 in hook plate 182. It will be apparent from the above that as the lower ends of'lower arms 80 and 82 move toward the lower ends of lower arms and 92 the hook plates 178 and .184 and the hook plates and 182 will be guided for reciprocation in opposite directions in a horizontal plane by virtue of the cooperaton between the coupling pins 210, 218, 226 and 234 with the horizontal guide slots 186, 192, 202 and198, respectively.

In order to facilitate centering the device upon the liange of a beam to be hoisted, a pair of guide pins, or fingers, 242 and 244 are adjustably mounted in a gap 246 which is maintained between the cross arms 206 and 208 of vertical guide plates 112 and 118 by means of a pair of spacer sleeves 248 and 250 which are respectively mounted on tie rods 166 and 168 between cross arms 206 and 208. The guide pin 242 has a cylindrical body portion provided with an inclined at guiding surface 252 at its lower end and a threaded mounting extension 254 of reduced diameter at its upper end. The guide pin 244 similarly has a cylindrical body portion provided with an inclined flat guiding surface 256 at the lower end and an upper threaded mounting extension 258 of reduced diameter. Guide pin 242 is secured in an appropriate position by means of a nut 260 and washer 262 bearing against the upper surfaces of cross arms 206 and 208. Likewise, mounting pin 244 is secured in position by means of a nut 264'which maintains a washer 266 against the upper surfaces of cross arms 206 and 208. It will thus be apparent that the guide pins 242 and 244 may be spaced apart any desired distance. In actual practice, it has been found convenient to space the guide pins 242 Vand 244 a distance slightly greater than the width of the flange of the` l-beam to be hoisted, with the guide surfaces 252 and 256 facing toward each other. Thus, when it is desired to place the device upon the ange of a beam to be hoisted the guide pins 242 and 244 will be positioned on opposite sides of the iiange. If the device is somewhat off-center, one of the guide surfaces 252 or 256 will engage the edge of the flange and cause the device to be centered on the flange.

In order to insure that the hook projections 188, y 194, 200 and 204 are all in the same horizontal plane before they are closed on a beam flange, the device should be seated squarely on the ange of the beam to be hoisted. To this end, the lower edges of clamp plates 162 and 164, hook plates 178, 180, 182 and 184, and cross arms 206 and 208 are all at and in the same horizontal plane and constitute the lower bearing surface of the device.

A typical cycle of operation will now be described. Assuming, as will usually be the case, that the beam lifting hook is locked in its open position as shown in FIG- URE 3, the device will be hoisted by lifting the hoist line and brought to rest on top of a ange 268 of an I- beam 270 to be hoisted. As the beam lifting hook is moved to this position, tension in the hoist line will not be effective to elongate the lazy tongs arrangement 22 due to alignment of the toggle links 124 and 126 of lock assembly 24. The lower bearing edges of clamp plates 162 and 164, hook plates 178, 180, 182 and 184,` and` cross arms 206 and 208, which, as was mentioned above, are all in a common horizontal plane, are brought to rest squarely on the top surface of flange 268 with guide pin 242 and hook projections 194 and 200 depending on one side of the ange and guide pin 244 and hook projections 188 and 204 depending on the opposite side of the ange. A workman will now grasp one or both of the handles 158 and 160 and force the toggle hinge 148 upwardly to unlock the lazy tongs arrangement 22. An upward pull on the hoist line will then serve to pull mounting bolt 36 upwardly within the cylindrical housing 30 to bottom coil spring 42. After the spring 42 is thus fully compressed, further tension in the hoist line will serve to elongate the lazy tongs arrangement 22 to close the set of grappling hooks 28 on the flange 268 of I-beam 270 by reciprocating them into engagement with the side edges of the ange as shown in FIGURE 6, The hoist line will then lift the device, and with it the beam`270, to place the beam in a desired location. After the beam is brought to rest, the hoist line will become slack to a degree suicient to permit the coil spring 42 to resume its normal extended position. The slack in the hoist line will then permit the lazy tongs arrangement 22 to collapse, bringing the set of grappling hooks 28 to an open position upon reciprocation of hook plates 178, 180, 182 and 184 by the lower ends of arms 80, 82, 90, 92. When the lazy tongs arrangement 22 collapses to the extent that the toggle links 124 and 126 are brought into alignment, the device will again be locked in the collapsed or open position and will be ready to be moved to another beam to be hoisted.

It is to be understood that a beam lifting hook of the invention is adapted for use under conditions which will subject it to great stress and that it will frequently collide with steel, or other hard, objects. All of the components parts of the device are thus desirably made of high quality steel in order to resist damage. noted also that the expedient of constructing the lazy tongs arrangement 22 of spaced, parallel arms and the rigidity provided by the clamp plates 162 andV 164 and the It is to be rods 166 and 168 results in a structure which is durable' and'rugged and which is not readily knocked out of alignment.

While a preferred embodiment of the invention has been shown and described, it will be apparent to those skilled in the art that changes can be made without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims. Accordingly, the foregoing embodiment is to be considered illustrative rather than restrictive of the invention, and those modifications which come within the meaning and range of equivalency of the claims are to be included therein.

The invention claimed is:

1. In a lifting device for grappling an object to beV hoisted, mounting means for securing said device to `a hoist line, said device having a vertical axis when suspendedfrom said mounting means, lazy tong means comprising a pair of upper arms pivoted at the upper ends thereof to said mounting means about a common axis and a pair of intersecting lower arms pivoted to each other about pivot means at the point of intersection and extending beyond said point of intersection, said lower arms being hinged at their upper ends to the lower ends of said upper-arms respectively, said lazy tong means being adapted to elongate in response to tension in said hoist line to move the lower ends of said lower arms toward eachother and to collapse in response to slack in said hoist line to move said lower ends of said lower arms apart, a lower frame assembly sli-dably connected to said lower ends of said lower arms and including horizontal guide surface means perpendicular to said vertical axis for guiding movement of said lower ends of said lower arms and vertical guide means mount-` 3. In a lifting device as defined in claim 2, said lost` motion means comprising a coil spring.

4. In a lifting device as defined in claim 2, said lost motion means comprising a vertically disposed cylindricalv housing, a coil compression spring within said housing, abutment means partially closing the upper end of said housing, a rod extending through said upper end of. -said housing and through said coil compression spring,.

said rod having an abutment member at its lower end, said coil ,compression spring being retained between said abutment means at the upper end of said housing and said abutment member at the lower end of saidrod, and means at the upper end of said rod for fastening said device to said hoist line.

5. In a lifting device asdened in' claim 1, lock means comprising first toggle link means hinged at one end to one of said lower arms and second toggle link means, hinged at one end to the other of said lower arms at` corresponding points above said point of intersection, toggle pivot means coupling the free ends of said iirst and said second toggle link means, whereby said device will be locked in an open position when said toggle link means are in alignment and will be adapted to close on said object when said toggle link means are out of alignment.

6. In a lifting device as recited in claim 5, `said lock means further comprising stop means to prevent said toggle pivot from moving below said corresponding points on said lower arms,

7. In a lifting device as recited in claim l5, said common axis, said point of intersection, said vertical guide` means,.and said toggle pivot being in vertical alignment.`

8. A beam lifting hook comprising mounting `means for securing said hook to a hoist line, said lifting hook having a vertical axis when suspended from said mounting means, a pair of trunnions projecting from said mounting means and defining a pivot axis, a first pair of spaced parallel upper arms pivoted at their upper ends to said trunnions and extending downwardly at an angle in a first direction, a second pair of spaced parallel upper arms pivoted at their upper ends to said trunnions and extending downwardly at an angle in a second direction, a first pair of spaced parallel lower arms pivoted at their upper ends to the lower ends of said rst pair of upper arms and extending' downwardly at an angle in said second direction, a second pair of spaced parallel lower arms pivoted at their upper ends to the lower ends of said second pair of upper arms and extending downwardly at an angle in said first direction, said first and said second pairs of lower arms intersecting at a point intermediate their ends below said trunnions, pivot means at said point of intersection intercoupling said first and said second pairs of lower arms, lock toggle means coupled between corresponding points on said first pair of lower arms and said second pair of lower arms above said point of intersection, said lock toggle means comprising a pair of links hinged together at a point between said point of intersection and said trunnions, and means coupled to the lower ends of said lower arms for closing said device upon an object to be hoisted, said last-mentioned means comprising first hook means coupled to said first pair of lower arms, second hook means coupled to said second pair of lower arms, and guide means for guiding movement of said hook means along guide surface means perpendicular to said vertical axis.

9. In a lifting device adapted to be secured to a hoist line and having a closed position for grappling an object to be hoisted and an open position, said device having a vertical axis when suspended from said hoist line, lazy tong means comprising first lower arm means and second lower arm means, said first and second lower arm means intersecting at a point intermediate their ends, pivot means at said point of intersection intercoupling said first and second lower arm means, vertical guide means for guiding movement of said pivot means along said vertical axis, means for engaging said object to be hoisted comprising first hook means and second hook means respectively coupled to said first and said second lower arm means, means for guiding movement of said first hook means along a guide surface perpendicular to said vertical axis on said second hook means, and means for guiding movement of said second hook means along a guide surface perpendicular to said vertical axis on said first hook means.

10. In a lifting device as defined in claim 9, said guide surfaces defining horizontal guide slots on said first and second hook means.

11. In a beam lifting hook for grappling a beam to be hoisted, a pair of spaced parallel clamping plates, first, second, third, and fourth parallel hook plates disposed between and parallel to said clamping plates, each of said hook plates having a horizontal slot extending lengthwise thereof, the rst and fourth hook plates having hooklike projections depending from one end thereof and the second and third hook plates having hook-like projections depending from the opposite end thereof, a first pair of spaced parallel hook actuating arms and a second pair of spaced parallel hook actuating arms, first pin means coupling one of said first pair of hook actuating arms to vsaid first hook plate and extending into the slot in said second hook plate, second pin means coupling one of said other pair of hook actuating -arms to said second hook plate and extending into the slot in said first hook plate, third pin means coupling the other of said second pair of said hook actuating arms to said third hook plate and extending into the slot in said fourth hook plate, and fourth pin means coupling the other of said first pair of hook actuating arms to said fourth hook member and extending into the slot in said third hook plate, whereby movement of said hook actuating arms causes said hook plates to reciprocate.said hook-like projections toward and away from the beam to be hoisted.

12. In a beam lifting hook as recited in claim 11, lazy tong means including said first and said second pairs of hook actuating arms, said pairs Iof hook actuating arms being pivoted about pivot means at a point of intersection, and vertical guide means for said pivot means comprising a pair of inverted T-shaped guide plates having vertical slots in the stems thereof, the cross arms of said guide plates being positioned between and parallel to said clamp plates.

13. In a beam lifting hook as defined in claim 12, said cross arms being located between said second and said third hook plates, means spacing said cross arms to define a gap therebetween, and guide pins adjustably mounted in said gap, said guide pins being spaced apart a distance slightly greater than the width of the beam to be hoisted whereby said device may be centered on said beam.

14. In a beam lifting hook as recited in claim 11, said clamp plates and hook plates having straight lower edges, said lower edges being located in a common horizontal plane whereby said beam lifting hook may be placed squarely on a liange of a beam to be hoisted.

15. A beam lifting device comprising means for securing the device to a hoist line, said device having a vertical axis when suspended from said means, lazy tongs means adapted to elongate in response to tension in said hoist line and to collapse in response to slack in said hoist line, said lazy tong means comprising a pair of intersecting lower arms pivoted to each other about pivot means at the point of intersection and extending beyond said point of intersection, hook means at opposite sides of said device for engaging a beam to be hoisted, means coupling said hook means to the lower ends of said lower arms to move said hook means together upon elongation of said lazy tong means and apart upon collapse of said lazy tong means, and means for guiding said movements of said hook means along guide surface means perpendicular, to said vertical axis.

16. In a lifting device as defined in claim 1, said vertical guide means comprising a guide plate having an upstanding arm and a vertical slot in said upstanding arm.

17. A beam lifting hook as recited in claim 8, further comprising vertical guide means for vertically guiding said pivot means at said point of intersection along said vertical axis.

18. In a lifting device as recited in claim 5, handle means on said toggle links for bringing said links out of alignment whereby said device will close on said Jibject to be hoisted in response to tension in said hoist References Cited by the Examiner UNTTED STATES PATENTS 274,189 3/ 1883 Hadlock 294-83 706,324 8/1902 -Lafferty 294-117 1,454,194 5/ 1923 Thomas 294-90 1,941,015 12/ 1933 Martel. 2,020,823 11/ 1935 Callahan 294-34 2,120,639 6/ 1938 Buente 294-86 2,352,017 6/ 1944 Scharpenberg 294-118 2,669,479 2/ 1954 Louckes 294-117 2,847,245 8/ 1958 Leslie 294-67 X 2,874,990 2/ 1959 Ianoff 294-86 FOREIGN PATENTS 1,205,708 8/1959 France.

739,720 1 1/ 1955 Great Britain.

81,410 3/ 1953 Norway.

OTHER REFERENCES German application B36860, November 1956.

GERALD M. FORLI-ENZA, Primary Examiner.

ERNEST A. FALLER, SAMUEL F. COLEMAN, G`

F. ABRAHAM, Assistant Examiners.

Claims (1)

1. IN A LIFTING DEVICE FOR GRAPPLING AN OBJECT TO BE HOISTED, MOUNTED MEANS FOR SECURING SAID DEVICE TO A HOIST LINE, SAID DEVICE HAVING A VERTICAL AXIS WHEN SUSPENDED FROM SAID MOUNTING MEANS, LAZY TONG MEANS COMPRISING A PAIR OF UPPER ARMS PIVOTED AT THE UPPER ENDS THEREOF TO SAID MOUNTING MEANS ABOUT A COMMON AXIS AND A PAIR OF INTERSECTING LOWER ARMS PIVOTED TO EACH OTHER ABOUT PIVOT MEANS AT THE POINT OF INTERSECTION AND EXTENDING BEYOND SAID POINT OF INTERSECTION, SAID LOWER ARMS BEING HINGED AT THEIR UPPER ENDS TO THE LOWER ENDS OF SAID UPPER ARMS RESPECTIVELY, SAID LAZY TONG MEANS BEING ADAPTED TO ELONGATE IN RESPONSE TO TENSION IN SAID HOIST LINE TO MOVE THE LOWER ENDS OF SAID LOWER ARMS TOWARD EACH OTHER AND TO COLLAPSE IN RESPONSE TO SLACK IN SAID HOIST LINE TO MOVE SAID LOWER ENDS OF SAID LOWER ARMS APART, A LOWER FRAME ASSEMBLY SLIDABLY CONNECTED TO SAID LOWER ENDS OF SAID LOWER ARMS AND INCLUDING HORIZONTAL GUIDE SURFACE MEANS PERPENDICULAR TO SAID VERTICAL AXIS FOR GUIDING MOVEMENT OF SAID LOWER ENDS OF SAID LOWER ARMS AND VERTICAL GUIDE MEANS MOUNTED ON SAID LOWER FRAME ASSEMBLY FOR VERTICALLY GUIDING SAID PIVOT MEANS AT SAID POINT OF INTERSECTION ALONG SAID VERTICAL AXIS.

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