US2646305A

US2646305A - Fulcrum grab

Info

Publication number: US2646305A
Application number: US131853A
Authority: US
Inventors: Sonderstrup Christian Andreas
Original assignee: RADA PRODUCTS CO
Current assignee: RADA PRODUCTS CO
Priority date: 1949-12-08
Filing date: 1949-12-08
Publication date: 1953-07-21
Anticipated expiration: 1970-07-21

Description

FULCRUM GRAB 3 Sheets-Sheet l F'iied Dec. '8, 1949 I IN VEN TOR. CHRIST/AN ANDREA5 SONDERSTRUP BY v MM m, f7 W y 1953 c. A. SONDERSTRUP FULCRUM GRAB Filed Dec. 8} 1949 3 Sheets-Sheet 2 INVENTOR. CHRIST/AN ANDQMS sovomsmw July 21, 1953 c. A. SONDERSTRUP FULCRUM GRAB 3 Sheets-Sheet 5 Filed Dec. 8, 1949 INVENTOR. MISTMAMIWS I \1 Patented July 21, 1953 UNITED STATE FULCRUM GRAB,

Christian Andreas Sonderstrup, Maywood, Ill.,

assignor to Rada Products Company, a corporation of Illinois Application December 8, 1949, Serial No. 131,853

8 Claims. (01.294-67) 1 -This invention relates to a material handling device and more particularly to a device for grab+ bing and holding sheet, strapped or bundledstock of relatively heavy material.

A general object of this invention is to provide a new and improved material handling device of the character described.

Another object is the provision of a device of the character described having a longitudinal axis of symmetry and means for positively attaching a hoist hook for lifting said device over the center of gravity thereof.

pivot points of said hook being selectively movable with respect to the frame to permit the hook to pick up material of diiferent Widths.

A further object is the provision of a material handling device of the character described having stabilizing hooks mounted on the ends of the frame at selective distances therefrom for graspingv the load carried by the device to prevent the load from slipping ofi the device.

Other objects and features of the device will be apparent from the following description of an embodiment thereof illustrated in the accompany drawings, in which: I

Fig. l is a perspective view of the material handling device of this invention supporting a load shown in dotted outline; I i

Fig. 2 is a plan view of the device showing the grab hooks in dotted outline as placed in their outer position;

Fig. 3 is a cross section of a portion of the device taken substantially along line 3-3 of Fig. 2

Fig. 4 is a side elevation of-the device of this invention;

Fig.5 is an end view of the deviceillustrated in the previous figures showing one of the grab hooks in dotted ou'tline swung to itsupper limited position; and

Fig. 6 is a fragmentary view of one of the tie bars showing a pivot pin of one of the grab hook arms therein and in dotted outline the same pivot pin in another position therein. I

v While there is shown'in the drawings and hereinafter described in detail a preferred form of the invention, it isto be understood that the invention is not limited to the particular form and arrangement shown. It is contemplated that various'changes may be made by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Relatively heavy sheets, strapped or bundled stock are usually handled by theuse of a crane or hoist, such cranes and hoists generally having a hoisting cable or chain and a hook on the lower end of the cable. Various means have been devised for gripping the stock or attaching the stock to the hook of thehoist in order to lift and transport the same. This invention is concerned with a grab adapted to grasp and hold relatively heavy stock and comprises generally a frame to which the hoist hook is attached and a pair of grab hooks, each mounted on an opposite side of the frame, said hooks being pivoted to the frame and depending therefrom to grab opposite sides of a load in order that the hoist may lift the same.

' The particular construction of the device ensures that each of the grab hooks once grasping a v bundle of material or other load will not release the load until an operator so desires. Also in handling relatively long sheets or bundled stock there is a tendency for the load to slip out of the grab hooks if the grab is not placed at the precise center of the load. The material handling device of this invention is also provided with means for retaining the load on the grab hooks regardless of the placement of the load on the hooks.

The frame of the material handling device is symmetrical about its longitudinal axis and has a center'supporting member It and a cross member mounted on each end of the center supporting member ID. Referring to Fig. 1, the center supporting member Ill comprises two channels-l2 placed back to back so that the legs l3 of the frame.

The channels 12 are in close contact'at their ends and are separated at their center point by a plate [4. The hoist cable l5 passes through a sheave 16 having a hoist hook l1 at its lower end. The plate M has an eye It therein adapted to receive the hoist hook ll so that the material handling device may be lifted and transported by the hoist'from place to place. Since the device is symmetrical about its longitudinal axis it is important that the hoist hook l llifts the device at a point substantially over its center'of gravity. The eye I8 in the plate M has an upper portion :9 shaped like an inverted V .(as

' shown in Fig. 3) so that the hoist hook ll will On each end of the center supporting member I2 is a cross member or tie bar 29 positioned normal to the longitudinal axis of the center member. Each tie bar has end portions which are free and unobstructed so that the grab hooks may be pivoted to these portions as hereinafter described.

In lifting heavy material it is important that the device used may be quick of operation and yet ensure a positive grasping of the material. This invention provides a grab hook 22 pivotally mounted on each side of the frame in such-a manner that once the hooks grasp a load the load has a tendency to strengthen the grasping force of the hooks on the load. Each grab hook comprises a material lifting member 23 mounted on and extending between a pair of arms 24. The

arms 24 are of a bell-crank shape and have at the upper end thereof, a pivot pin 25 rigidly fixed to the arm 24. The pivot pin extends through an aperture 25 in the tie bar 20 so that the grab hook may swing about its pivot. To strengthen the arms, a tie rod 29 extends between the arms above the material lifting members 23. In Fig. 1 the grab hooks 22 are illustrated as placed so that the pivot pins 2'5 extend through apertures 26 in the tie bars closely adjacent the center support member [2 of the frame. In this position the grab hooks may lift relatively narrow bundles of stock or sheet material.

Referring more particularly to Figs/5 and 6, each tie bar is provided with a pair of spaced pivot apertures 26 connected by a horizontal slot 2'! smaller in width than the diameter of the apertures 25. The pivot pin has a flat surface 23 which if aligned with one side of the slot 2? will permit the pivot pin to be moved from one of the apertures 26 to the other in each free end of the tie bars 26. The particular position of the grab hooks in order to effect the movement of the pivot pins from one aperture to another is illustrated in Fig. 5. When the arms 24 are in the position such that the material lifting member 23 depends below the frame of the device the pivot pin is in the position illustrated in the right hand portion of Fig. 5. If the grab hook is moved upwardly to the position shown in dotted lines in Fig. 5 the pivot pin then assumes the position illustrated in dotted lines shown in the center of Fig. 6 so that the pin may be moved between the pivot apertures. In this manner the grab hooks may be moved from the positions shown in solid lines in Fig. 2 to the position illustrated in dotted lines in Fig. 2.

.As stated above the grab hooks are so constructed that a load placed thereon tends to strengthen the grasping effect of the hooks on the load. This is accomplished by providing the grab hooks with arms of a bell-crank shape. 7 stop detent is mounted on each arm and has a portion extending outwardly above the tie bar 25. This stop detent 36 prevents the material lifting member 23 from swinging inwardly toward the'center of the device past a point directly below the pivot pin on the upper end of its supporting arms 24. Thus any load applied to the material lifting members 23 must be transferred through the arms, the pivots, and the frame to the hoist hook and the load will provide a force on the material lifting members creating a moment about the pivot pins 25 tending to force the material lifting member toward the center of the device. The stop detent also provides a convenient means for aligning the flat-side 28 of the pins 25 with the side of the slot 21, for when the grab hook is pivoted to the position shown in dotted lines in Fig. 5, the stop detent again contacts the upper edge of the tie bar 20 and in this position, the pivot pins may be moved through the respective slots as desired.

The material lifting members 23 are generally of an angle iron construction and have an upwardly extending flange 23a which is attached to the depending end of the arms 24, and a flange 23b extending at right angles to the flange 23a. As more clearly seen in Figs. 2 and 4, the center portion of the flange 23b is cut away at to leave a portion in the center of the flange which will not contact any load picked up by the grab hooks. Opposite the cut-out portion of the flange 23b is a small upwardly extending cut-out portion 36 in the upwardly extending flange 23a. In picking up a load of bundled or strapped stock or sheets which. may be placed upon skids, the material lifting members 23 may be placed under the load and the cut-out portions will allow the member to straddle the straps or skids. The material for which the device is designed to lift is quite heavy so that the cutaway portions of the lifting member 23 greatly aid in quick and efficient handling and stacking of such material.

Material placed on skids or bundled or strapped stock is often stacked by workers so that a space is provided between each bundle by placing wedges between the bundles. As de scribed above the cut-away portions of the material lifting members 23 allow the members to be placed under the material to be lifted, yet because of the particular placement of the wedges it may not be possible to grasp a bundle of material at its center point. In such instances the weight of the material being lifted will not be balanced in the device about the hoist grab but will tip longitudinally of the device in one direction or the other. To prevent unevenly lifted bundles from slipping longitudinally out of the grasp of the material lifting members, auxiliary hooks it are removably attached to the ends of the frame to stabilize the load within the grasp of the grab hooks. Each stabilizing hook comprises a bell-crank shaped arm 4| having a material hooking member 42 at one end thereof and a chain 43 connected to the other end of the arm for removably attaching the stabilizing hook to th frame of the handling device. A bracket 44 is provided at the elbow of each arm Hi to present a convenient hand hold for placing the stabilizing hooks in contact with the load. As loads vary in length the stabilizing hooks 4!] may be placed at variable distances from the frame by grasping selective links of the chain 43 in the slot '45 provided in a bracket 4'6 mounted upon the end of the channel members [2 on each end of the frame. One stabilizing hook it! is provided for each end of the material lifting device so that a bundle of material may be effectively grasped on four sides as diagrammatically illustrated in Fig. 1.

In lifting and handling relatively heavy materials it is often necessary to provide a means for guiding the material as transported by the hoist through doorways and in and about machinery in a plant. An operator having the material handling device of thisinvention attached to a hoist may easily guide the material lifted thereby by the use of handles inserted in retaining collars 51 mounted on one opposite pair of :arms at one end of the device as illustrated .in Fig. 1. The primary use of the baneffect of the hooks. Also I have provided novel means for ensuring that a load grasped by the device will not slip longitudinally out of the grasp of the material lifting members and a. device easily and quickly adaptable to handle various size loads. i 1

Iclaim:

l. A material handling device comprising, a frame symmetrical about a longitudinal axis and having a center supporting channel and a tie bar attached to each end thereof normal thereto, said tie bars each having a pair of spaced pivot apertures connected by a slot smaller in width than the diameter of said apertures, a pair of grab hooks each mounted on an opposite side of said frame each comprising, a pair of bellcrank shaped arms, a material lifting member extending between and attached to the lower end of the arms, a pivot pin attached to the'upper end of each arm and extending through one of said pivot apertures for pivotally mounting each arm respectively to a tie bar, said pivot pins having a flat side permitting said pin to be moved through said slot between said pivot apertures.

2. A material handling device comprising,;a frame symmetrical about a longitudinal axis and having a center supporting member and a tie bar attached to each end thereof normal thereto, a grab hook mounted on each side of said frame comprising, a' pair of bell-crank shaped for limiting the movement of said grab hooks past a point directly below said pivot in one difoot portion to be placed under material resting on skids.

4. A material handling device comprising, a frame having a center supporting member and a tie bar mounted on each end of said center member, a pair of grab hooks mounted on opposite sides of said frame, said hooks being movable with respect to each other for grasping material of different widths, and. a stabilizing hook adjustably attached to an end of said frame for grasping the material to prevent slipping thereof longitudinally out of the grip of said grab hooks.

5. A material handling device as claimed in claim 4 wherein a stabilizing'hook is removably attached to each end of said frame.

6. A material handling device comprising, a

frame having a center supporting member and a at a selected link thereof whereby said stabilizrection and for aligning the flat side of said pivot with said slot when said arms are moved in the other direction to a position with said stop detent again contacting the top of the tie bars. 3

3. A material handling device comprising, a frame symmetrical about a longitudinal axis and having a center supporting channel'and a tie the center of the device, said foot portion being ing hooks may be removably fastened to the frame at selected distances therefrom.

'7; A material handling device comprising, a frame symmetrical about a longitudinal axis and having a center supporting channel, a tie bar rigidly attached to each end of said channel normal thereto, a pair of grab hooks each mounted on an opposite side of said frame each comprising, a pair of bell-crank shaped arms, a material lifting member extending between and attached to the lower end of the arms, pivot means swingably securing the upper end of each arm to one of said tie bars, including cooperating parts in the form of a stud and aperture, one partbeing on the arm and a plurality of the other part being on the tie bar in spaced relation therealong, and means for selectively positioning said pivot means at a plurality of points along said tie bars for moving said grab hooks relative to said longitudinal axis.

8. A material handling device comprising, a frame symmetrical about a longitudinalaxis and having a center supporting channel, a tie bar rigidly attached to each end of said channel normal thereto with said tie bars being parallel, a pair grabhooks relative to said longitudinal axis.

CHRISTIAN ANDREAS SONDElFtSTRUP.

References Cited in the file of this patent Tj'NITED STATES PATENTS Number. Name Date 1,822,629 McIlvried Sept. 8, 1931 2,198,652 Cullen et al Apr. 30, 1940