US3485388A

US3485388A - Core grab

Info

Publication number: US3485388A
Application number: US777304A
Authority: US
Inventors: William C Bohne
Original assignee: WILLIAM C BOHNE
Current assignee: WILLIAM C BOHNE
Priority date: 1968-11-20
Filing date: 1968-11-20
Publication date: 1969-12-23
Anticipated expiration: 1986-12-23

Description

Dec. 23, 1969 w. c. BOHNE 3,485,388

CORE GRAB Filed NOV. 20, 1968 2 Sheets-Sheet 1 I N VEN TOR. WILL/Al) CZ BOHNE ATTORNEYS Dec. 23, 1969 w. c. BOHNE 3,435,333

CORE GRAB Filed Nov. 20, 1968 2 Sheets-$heet 2 I Hawai I i il INVENTOR. WILL/AM C. BOH/VE 1 BY I I @m 1am A TTURNEYS United States Patent 3,485,388 CORE GRAB William C. Bohne, 30 George St., Wellsville, N.Y. 14895 Filed Nov. 20, 1968, Ser. No. 777,304

Int. Cl. B66c 1/54 US. Cl. 2141 Claims ABSTRACT OF THE DISCLOSURE A grab adapted to be inserted into the hollow cylindrical core of a heavy roll and then expanded to frictionally grip the core so that the roll may be lifted by the .grab.

BACKGROUND OF THE INVENTION Core grabs of various types have been widely used in industry for picking up heavy rolls, such as a roll of paper. All those of which I am aware, however, suffer from one or more disadvantages, including their inability to be automatically locked in place and released from within the roll core or the fact that their use results in excessive damage to the core and/ or the material mound thereon.

Excessive core damage results when the grablis provided with sharp teeth which are adapted to dig into the walls ofthe core, or the design of the grab does not permit the grab to apply pressure uniformly along the length of the core. 7

SUMMARY OF THE INVENTION The present invention is directed to an expansible core grab of the type adapted to pick up a roll of material solely by frictional engagement with the walls of a core on which the material is wound.

The present core grab generally includes an operating rod by which the grab may be suspended, a barrel which is supported on the operating rod so as to permit both relative rotation and reciprocation therebetween, and a plurality of slips or shoes which are supported on the barrel for movement between core engaging and releasing positions upon relative movement of the rod and barrel.

Upon lowering of the grab into a core, the slips are adapted to engage the end of the core and/or roll and be automatically positioned thereby centrally of the core and in preliminary engagement therewith. Thereafter, the roll may be picked up by merely elevating the operating rod, which serves to automatically drive the slips into full lifting engagement with the core. When the operating rod is lowered in order to position the roll on the ground or other supporting surface, the slips are automatically disengaged and the grab released from within the core.

I I DRAWING The nature and mode of operation of the grab of the present invention will be more fully understood by refer- :present invention, with portions thereof broken away for clarity;

FIG. 2 is a sectional view taken generally along'the line 2-2 in FIG. 1;

FIG. 2a is a sectional view similar to that of FIG. 2. but showing the arrangement of parts when the grab is inserted into a core of a roll; I

FIG. 2b is a sectional view similar to that of FIG. 2, but showing the arrangement of parts when the grab is employed to lift the roll;

FIG. 3 is a sectional view taken generally along the line 3-3 in FIG. 1;

FIG. 4 is a schematic diagram illustrating various stages of operation of the grab; and

3,485,388 Patented Dec. 23, 1969 FIG. 5 shows an attachment for the core grab of th present invention.

DETAILED DESCRIPTION The core grab of the present invention, which is designated as 1 in FIG. 1 generally includes an operating rod 2; a barrel, which is designated generally as 4 and mounted on rod 2 so as to permit both relative reciprocation and rotation therebetween; and three identically shaped core engaging slips or shoes 6-8, which are movably mounted on barrel 4. Core grab 1 may be suspended from an elevated hoist or other suitable carrier, not shown, by a lifting link 10, which is bored as at 10a to freely receive a swivel pin 11 whose lower end is threaded into operating rod mounted fitting or collar 12. This arrangement permits rotation of the operating rod 2 with respect to lifting link 10 for the purpose of actuating the grab, as will be more fully hereinafter described.

Operating rod 2 is provided adjacent the lower end thereof with a screw thread afiixed guide block or nose 14 of inverted conical shape, which serves to facilitate entry or introduction of the grab into a hollow, cylindrical core C of a roll of material R to be handled. Rod 2 is provided immediately above nose 14 with a suitably affixed or integrally formed, conically shaped, slip operating cam 16. Adjacent the upper end of operating rod 2, there is provided a suitably aflixed guide sleeve 18, which, together with rod 2 is bored to receive a pin 20. The radially oppositely projecting

ends

21, 22 of pin 20 serve to movably interconnect rod 2 and barrel 4, as will be described.

Barrel 4 includes a cover or outside sleeve 23; upper and lower sleeve like

cam elements

24, 25, which are disposed concentrically inwardly of cover 23 and afiixed thereto in an axially spaced, relatively fixed relationship by suitable means such as machine screws 26, 27, respectively; and a heavy, metal slip guide 28, which is afiixed to lower cam element 25 by a plurality of machine screws 29.

As best shown in FIGS. 1 and 2-2b, operating rod 2 is guidingly supported for movement within barrel 4 by slip guide 28, which is provided with rod receiving through bore opening 30, and

cam elements

24, 25, which slidably receive rod guide sleeve 18.

Now referring particularly to FIG. 4, it will be understood that facing

rims

32, 33 of

cam elements

24, 25, respectively, cooperate to define an annularly extending, radially opening groove 35, which is adapted to receive

pin ends

21, 22. Rim 32 of upper cam element 24 is provided with a pair of downwardly opening deep slots or

recesses

36, 38, which are bounded by curved entrance or

camming surfaces

36a, 38a and

tapered exit surfaces

36b, 38b, and a pair of intermediate downwardly opening shallowslots or

recesses

40, 42 which are bounded by curved entrance or camming surfaces 40a, 42a and tapered exit surfaces 40b, 42b, respectively. Slots 36-42 are equally spaced annularly of rim 32 at intervals of such that pin ends 21, 22 may be alternatively disposed in

slots

36, 38 or

slots

40, 42. Rim 33 of lower cam element 25 is provided with four upwardly opening shallow slots or

recesses

43, 45, 47, 49, which are arranged at 90 intervals annularly of rim 33 and bounded by tapered entrance or camming surfaces 43a-49a and tapered exit surfaces 43b-49b, respectively. By arranging slots 43-49 in an annularly offset relationship to slots 36-42, lower rim camming surfaces 43a-49a are placed in vertical alignment with

slots

36, 40, 38, 42 and upper rim camming surfaces 3611-4211 are placed in vertical alignment. with

slots

49, 45, 43, 47, respectively. Thus, it will be apparent that when operating rod 2 is reciprocated in opposite directions with respect to

cam elements

24, 25,

pin ends

21, 22 are adapted to be moved alternatively into slots 36-42 and 43-49, so as to effect rotation of operating rod 2 with respect to barrel 4 in a clockwise direction, as indicated in FIGURE 4 by arrow 50.

Referring to FIGS. 1, 2, 2b and 3, it will be seen that the outer surface of slip guide 28 is defined by a first cylindrical portion 52, a first frustoconical portion 53, a second cylindrical portion 54 and a second frustoconical guide portion 55, which surface portions are aligned and disposed concentrically of slip guide bore opening 30.

Slip guide 28 is provided with three identically shaped slip guide slots 56-58, which are adapted to supportedly receive slips 6-8, respectively. Slots 56-58 extend radially of bore opening 30 and are disposed in an equally spaced relationship circumferentially of slip guide 28. By referring particularly to slot 56, it will be understood that each of the guide slots is provided with a relatively narrow, trapezoidal shaped lower end portion 56a, which opens through bore opening 30 and

surface portions

54, 55; and a relatively wide trapezoidal shaped upper end portion 56b, which is disposed in communication with slot portion 56a and opens through bore opening 30 and

surface portions

52, 53. A retaining sleeve 60, suitably affixed to first cylindrical surface portion 52 as by machine screws 61, may be employed to close the outer end of slot portion 56b to retain slip 6 supported therein.

Specifically referring to slip 6, it will be understood that each of slips 6-8 includes an elongated, arcuate metal casting 65 having a lengthwise projecting guide blade 66 and a radially extending arcuate flange 67, which are welded or otherwise affixed at the upper end thereof. Casting 65 is formed with serrated outer and smooth

inner surfaces

68, 69 respectively, which are adapted to be disposed substantially concentrically of operating rod 2. Smooth inner surface 69 opens adjacent the upper and lower ends of casting 65 into upper and lower conically

shaped surface segments

70, 71, which are identically configured to slip guide surface portion 55 and slip operating cam 16, respectively.

Slip guide blade 66 is formed with a relatively narrow, trapezoidal shaped web portion 66a and a relatively wide trapezoidal shaped head portion 66b, which are adapted to be loosely received within

slot portions

56a and 56b, respectively. Slip 6 is suspended from slip guide 28 by blade head portion 66b, whose movement radially of slip guide 28 within slot portion 56b is limited by operating rod 2 and retaining sleeve 60. The force of gravity serves to normally maintain slip 6 in its lower or nonexpanded position, wherein blade head portion 66b is disposed adjacent the lower, radially inner end of slot portion 56b in engagement with operating rod 2.

Operation of core grab 1 will be best understood by first referring to FIGS. 1 and 2, which illustrate the parts of the grab in the rest or inoperative positions they normally assume when the grab is suspended by lifting link 10 prior to a roll lifting operation. In this condition of the grab, barrel 4 is suspended from operating rod 2 by

pin ends

21, 22, which are received within shallow, upper

cam element slots

40, 42, and slips 6-8- are retained by gravity in their fully retracted positions. Also, in this condition operating cam 16 is spaced slightly below slips 6-8.

When, as indicated in FIG. 2a, operating rod 2 is lowered to position the grab within core C of roll R, the arcuate flanges of slips 6-8 are placed in abutting engagement with the end of core C and constrained thereby against further movement axially of the core. Immediately thereafter, gravity induced downward movement of slip guide 28 relative to slips 6-8 initiates radially expansive movement of the slips outwardly through slots 56-58, due to the camming action of slip guide surface 55 on the upper conically shaped surface segments of the slip castings. During continued downward movement of operating rod 2, pin ends 21, 22 are moved downwardly out of supporting engagement with upper

cam element slots

40, 42 into engagement with lower cam element surfaces 45a, 49a, which serve to cam the pin ends into slots 45, 49, as shown in phantom at 21a, 22a in FIG. 4. This operates to arrest vertical movement of rod 2 and effect rotation thereof in a clockwise direction through an angle of approximately 45 with respect to barrel 4 whose motion has been previously restrained due to engagement of slips 6-8 with core C. Furthermore, engagement of pin ends 21, 22 with lower cam element 25 serves to tap or drive slips 6-8 via the camming action of slip guide 28, so as to insure that the slips are disposed in centered, firm frictional engagement with the core. It will be noted that since the slip blades are loosely fixed within slip guide slots 56-58, slips 6-8 are permitted to tilt slightly with respect to the axis of operating rod 2, as shown in FIG. 2a, thereby rendering it easier to center the slips and control initial contact thereof with the core.

R011 R may now be lifted by merely lifting operating rod 2 to position the grab parts, as shown in FIG. 2b. When operating rod 2 is lifted, pin ends 21, 22 are first moved out of lower cam element slots 45, 47 vertically into engagement with upper cam element surfaces 38a, 36a, which serve to cam the pin ends into

deep slots

38, 36, as shown in phantom at 21b, 22b in FIG. 4, thereby effecting rotation of operating rod 2 in a clockwise direction through an angle of approximately 45 with respect to barrel 4. Continued upward movement of operating rod 2 serves to position operating cam 16 in camming engagement with the lower conically shaped surface segments of the slip castings, whereby the lower ends of the slips are moved radially outwardly of the operating rod to position the serrated outer surfaces of the slip castings concentrically of the rod and in firm frictional engagement with the core. Thereafter, roll R may be lifted due to frictional engagement of the slips with core C, during which time the weight of the roll, slips and barrel is supported by slip operating cam 16. The distance through which slips 6-8 may be moved radially of rod 2 is determined by the lengths of slip guide slots 56-58 and the permissible relatively upward movement of rod 2, as determined by the depth of

upper cam slots

36, 38. In any case, however, it is preferable to form

slots

36, 38 sufficiently deep to prevent pin ends 21, 22 from contacting the closed ends thereof and thus insure that the weight of the article to be lifted is never supported directly by the pin ends. It will be understood that slip guide 28 and/or barrel 4 is made sufficiently heavy, so as to act as a stop or restraining means for the slips and prevent movement thereof out of the core when engaged by cam 16.

The grab may be released from within core C by merely lowering roll R onto the ground or other supporting surface and thereafter permit operating rod 2 to move downwardly into its full down position, indicated in FIG. 2, during which time pin ends 21, 22 are moved downwardly out of slots 38, 26 and cammed by lower element cam surface 47a, 43a into

slots

47, 43, as indicated in phantom in FIG. 4, at 21c, 22c. Movement of pin ends 21, 22 into lower

cam element slots

47, 43 again serves to rotate operating rod 2 in a clockwise direction through an angle of approximately 45. Thereafter, the grab may be removed from core C bymerely elevating operating rod 2 to position the pin ends 21, 22 in upper

cam element slots

42, 40, as indicated at 21d, 22d in FIG. 4, whereupon the pin ends serve to lift slip guide 28 in order to remove guide surface portion 55 from tight camming engagement with slips 6-8 and thus permit the slips to fall by gravity into their original positions and out of engagement with the core. The grab parts are now returned to their positions indicated in FIG. 1 except that operating rod 2 has been rotated through with respect to barrel 4 so as to reverse the positioning of pin ends 21, 22 with respect to upper

cam element slots

40, 42.

FIG. 5 illustrates an attachment for the above described core grab which permits it to be used for lifting rolls, which are originally supported on the ground with their cores disposed horizontally. The attachment, which is generallydesignated as 80 includes a sleeve 81"having one end thereof closed by a radially' extending end plate 82, which is provided with a through bore opening 83 disposed in axially alignment with sleeve SL Attachment 80 may be suspended-from an elevatinghoist or other suitable carrier, not shown, by a generally U-shaped lift rod 84, which is pivotally affixed to sleeve 81 adjacent the open end thereof by aligned sleeve mounted bearings 85. Attachment 80 may be mounted on grab 1 by first removing lifting link and thereafter inserting swivel pin 11 through bore opening 83 and threading the swivel pin into operating rod collar 12. Thereaftenbperating rod 2 may be freely rotated with respect to'sleeve 81 and sleeve 81 in turn freely reciprocated relative to barrel 4. l 4

During operation of agrab having attachment 80, the grab would be pivoted from its normal vertically disposed position illustrated in phantom at 1a in FIG. 5, into a horizontally disposed position about the axis of bearings 85 to permit the grab to be moved into the horizontally disposed core C either by moving the upper end of rod 84 in the direction indicated by arrow'90 or by manually pushing against the attachment end plate 82. Thereafter, when lift rod 84 is lifted, attachment sleeve 81 and thus the grab and roll will tend to pivot about the axis of bearings 85 in the direction indicated by arrow 91 into upright position, indicated at 81a in FIG. 5. Thethus described movement serves to bring the slip operating cam 16 into engagement with slips 6-8, as indicated in FIG. 2b. The grab may be subsequently separated from the roll by the procedure heretofore discussed.

While the present invention has been described with particular reference to the preferred embodiment thereof wherein three slips are employed, and wherein upper and lower cam elements are shaped to effect a 180. rotation of the operating rod during each full cycle of grab opera tion, it will be understood that the invention is not limited thereto. In this respect, it will be apparent that any de sired number of uniformly spaced slips may be employed and the number of slots provided in the upper and lower cam elements may be varied. Also, the upper and lower cam elements may be inverted and carried by the rod in which case the projecting pins would be carried by the barrel. Further, the grab of the present invention may be employed to lift reels, pipes or other articles having either a separate supporting core or a hole provided centrally thereof. Thus, the term core is used generically herein and in the appended claims to include a hole, which is provided in an article and into which the grab may be inserted for the purpose of handling the article. In a like manner, the term end of the core is meant to include the end surface of a roll supported by the core as well as a portion of an article bounding a hole into which the grab may be inserted. Further, it will be understood that the projecting pins may be replaced by rollers, sphere projections or the like, and thus the term pin means is meant to include any device adapted to cooperate with the cam elements for the purpose of interconnecting the rod and barrel for relative movement.

Whatis claimed is:

1. A grab adapted to be inserted within a hollow core provided in an article and expanded into frictional engagement with said core to permit lifting of said article from a supporting surface, said grab being adapted to release said core upon subsequent lowering of said article onto a supporting surface, said grab comprising:

an operating rod, said rod being connectible adjacent one end thereof to a lifting device and having cam means disposed adjacent an other end thereof; restraining means disposed on said rod for axial movement relative thereto; means to connect said restraining means with said rod;

and a plurality of slips disposed around said rod for axial movement relative thereto, said slips being adapted to be inserted into said core and when inserted being adapted to be alternately engaged and released by said cam means for movement outwardly of said rod into and out of frictional engagement with said core to grab and release said article during successive first and second relative longitudinal movements of said rod and said restraining means, said slips having means engageable withan end of said core through which said slips are inserted to limit movement of said slips into said core, said restrain ing means being movable into a position when said slips are inserted in which said slips are restrained in engagement with said core end, said first longitudinal movement being obtainab e by longitudinally inserting said other end of said rod into said core to position said slip means in engagement with said core end and-said restraining means in said position and longitudinally retracting said rod with respect to said core to force said rod cam means into engagement with said slips and'thereby effect movement of said slips into engagement with said core and lift ing of said article from a supporting surface, and said second longitudinal movement being obtainable upon lowering said article onto a supporting surface by longitudinally moving said rod inwardly of said core and retracting said rod with r spect to said core to permit said connecting means to remove said restraining means from said position and release said slips from said rod cam means, thereby permitting release of said slips from said core in order to release said grab from said article.

2. A grab according to claim 1, wherein said restraining means includes cam means, the last said cam means cooperating with said rod cam means to force said slips into frictional engagement with said core.

3. A grab according to claim 1, wherein connecting means includes cooperating pin means and cam element means, one of said pin and cam el ment means being carried on said rod and the other of said pin and cam element means being carried on said restraining means, said cam element means defining relatively shallow and relatively deep recesses, said pin means being alternately receivable within said recesses upon said first and second relative longitudinal movements.

4. A grab according to claim 3, wherein said restraining means includes second cam means, said first and second relative longitudinal movements serving to move said second cam means and said rod cam means between first and second relatively spaced positions, said slips being movable into engagement with said core when said cam means are in said first position and movable out of en'- gagement with said core when said cam means are in said second position, said cam means being in said first position when said pin means is receivable within said deep recess and said cam means being in said second position when said pin means is receivable within said shallow recess.

5. A grab according to claim 4, wherein said cam element means are carried by said restraining means and said pin means are carried by said rod.

6. A grab according to claim 4, wherein said restraining means is in the form of a barrel disposed concentrically of said rod, said barrel includes a plurality of guide slots extending radially of said rod, each said slip including blade means receivable one within each of said slots, said slots and blade means serving to constrain said slip means for movement substantially radially of said rod when said cam means are moved between said first and second positions.

7. A grab according to claim 6, wherein said second cam means is defined by a frustoconical cam surface of said barrel, said rod cam means is defined by a frustoconical cam surface, said conical cam surfaces being disposed in facing relationship and axially aligned with said rod, said slots extending through said barrel cam surface,

said slips being elongated lengthwise of said rod, said slips having arcuate outer side surfaces engageable with said core and arcuate-inner side surfaces engageable with said rod, each of said slips having adjacent one lengthwise end thereof a cam follower surface engageable with said rod cam surface and having adjacent an opposite lengthwise end thereof a cam follower surface engageable with said barrel cam surface, said blade means projecting lengthwise of said slips, and said core end engaging means projecting radially of said slips from adjacent said opposite end thereof.

8. A grab according to claim 7, wherein each said slot includes a relatively narrow slot portion and a rela tively wide slot portion, and each said blade means includes a relatively narrow web portion receivable within said narrow slot portion and an enlarged head portion receivable within said wide slot portion, said enlarged head portion supporting said slip within said slot, and said slots being tapered such that when said rod is vertically supported by a lifting device said blades tend to fall by gravity within said slots to position said slips in engagement with said rod.

9. A grab according to claim 8, wherein said head portions of said blades are loosely received within said wide portions of said slots, such that said slips may radially tilt with respect to the axis of said rod.

10. A grab according to claim 1, wherein a lifting attachment is provided to connect said rod to said lifting device, said attachment including a sleeve;

swivel means, said swivel means being adapted to connect said sleeve adjacent one end thereof to said one end of said rod such that said sleeve is disposed concentrically of said rod and has the other end thereof disposed intermediate said rod ends, said swivel means joining said Sleeve and rod such that they are relatively rotatable about the axis of said rod but joined for simultaneous axial movement relative to said restraining means; and

attachment lift means, said lift means being connectible to said lifting device and being pivotally aflixed to said sleeve adjacent said other end thereof for pivotal movement about an axis disposed normal to the axis of said rod.

References Cited UNITED STATES PATENTS 1,892,442 12/ 1932 Wickersham. 3,104,016 9/1963 Harry. 3,393,003 7/1968 Magee 294---96 GERALD M. FORLENZA, Primary Examiner FRANK E. WERNER, Assistant Examiner US. Cl. X.R. 294-96, 110