US3498484A

US3498484A - Overhead attachment for the boom point of cranes

Info

Publication number: US3498484A
Application number: US757610A
Authority: US
Inventors: Alfred Tucci
Original assignee: Individual
Current assignee: Individual
Priority date: 1968-09-05
Filing date: 1968-09-05
Publication date: 1970-03-03
Anticipated expiration: 1987-03-03

Description

Max:113; 1970" 33mm 3,498,484

OVERHEAD ATTACHHERT FOR THE BOOM POINT OF CRANES Filed Sept. '5. 1968 3 Sheets-Sheet 1 m i2 is I g .N a N ALFRED TUCCI INVENTOR.

1/15 Arromvsy March 3, 1910 vA. YTUCCI 3,49

OVERHEAD ATTACHMENT FOR THE BOOM POINT OF CRANES Filed Sept. 5, 1968 3 Sheets-Sheet 2 ALFRED TUCCI lN VEN TOR.

I 4 45 477'0RJVE/ March 3, 1970 V A. TUCCI 3,49

- OVERHEAD ATTACHMENT FOR THE BOOM POINT OF CRANES Filed Sept. 5, 1968 3 Sheets-Sheet 5 aw I N 9 ALFRED TUCCI 1N VENTOR.

xf/s d fraelvgx ited States Patent 3,498,484 OVERHEAD ATTACHMENT FOR THE BOOM POINT OF CRANES Alfred Tucci, 2510 Fernwood Ave., San Jose, Calif. 95117 Filed Sept. 5, 1968, Ser. No. 757,610 Int. Cl. B66c 23/68; E04g 1/22 U.S. Cl. 214-130 3 Claims ABSTRACT OF THE DISCLOSURE Background Boom type cranes are -well known in the art. Such cranes are constructed with sheaves or pulleys at what is commonly called boom point which is at the extreme outer end of the boom. Claws, grapples, buckets and the like on the end of a cable trained over the sheave a pulley at boom point can only be elevated to the level of boom point.

The present invention entails the provision of an overhead attachment for the boom point of a crane. Such at tachments are for the purpose of elevating objects, material and tools beyond and above the level of boom point. The present invention further entails the provision of an attachment for boom points which is self leveling such as to remain horizontal compensatory to the angle or movement of the boom.

Various devices and mechanisms of the self leveling type boom tip supports are found in the art. Such known self leveling tip supports usually consist of platforms, tables, seats, tongues and the like requiring gear, hydraulic and/ or complex lever, embodying mechanisms in construction and operation. A search of the art reveals such known deveices in class 314 and subclasses thereof. The closest art appears to be found in US. Patents No. 2,073,998 to Raby, dated Mar. 16, 1937; No. 2,454,840 to W;- W. Ryan, dated Nov. 30, 1948; No. 2,483,811 to Cullen, dated Oct. 4, 1949; and No. 3,153,510 to Brannfors et al. dated Oct. 20, 1964.

Statement of invention The present invention contemplates the provision of a self-leveling overhead attachment for the boom points of cranes coordinated with the operation of the boom in such a way as to automatically compensate for charges in angular disposition of the boom'in a simple yet efiective manner. I I

The present invention has as an object the provision of a boom point attachment by which work, material and articles can be raised above boom point under bridges, ceilings and overhead structures. In this connection it is a further object to provide a boom point attachment which will enable level handling of work, material and articles from ground level up to elevations above the reach of boom point dependent upon the raising and/ or lowering of the boom in its usual manner of operation.

It is another object to provide a parallelogram carrier for a platform table at the boom point of a crane and means for stabilizing such platform table to enable the performance of work therefrom above and beyond boom point.

It is yet another object to provide a self-adjusting com- 3,498,484 Patented Mar. 3, 1970 ice pensator for the overhead attachment of the present invention for automatically maintaining the platform table thereon horizontal during and by up and down movement of the boom.

These and other objects and advantages of the present invention will become more apparent in the following description and three sheets of drawing in which:

FIG. 1 is a side elevation of a boom type crane having the boom type attachment embodiment of the present invention applied thereto.

FIG. 1A is a fragmentary illustration of the boom and attachment in lowered position.

FIG. 2 is an enlarged fragmentary plan view of a level compensator embodied in FIG. 1.

FIG. 3 is an enlarged fragmentary perspective view of the boom point of the boom of FIG. 1, parts of which are broken away for purposes of illustrating the boom point attachment shown in lowered condition.

FIG. 4 is an enlarged fragmentary perspective view similar to that of FIG. 3 showing the boom point attachment in raised condition relative to the boom.

General description Referring to FIG. 1 a crane 5 is shown having a cab 6 turntable mounted on a wheeled carriage 7 and having a boom 12 pivotally mounted as at 8 on the cab such as to enable rotation of the boom radially from the carriage 7. Conventional cables 9 extending from the cab 6 and winch mechanism therein (not shown) have their opposite ends 9' secured to the boom 12 adjacent boom point generally designated 11 in the drawing. The cables 9 are for raising and lowering the boom 12 relative to the pivot mount 8 at the cab 6.

Detailed description Referring to FIGS. 3 and 4 the overhead attachment 10 of the present invention consists of two pairs of L-

shaped arms

16 and 17 pivotally conected at their ends F and G, respectively, to a table 13 for receiving and supporting objects to be moved.

The opposite ends B and C of the

arms

16 and 17 are pivotally connected to a compensator 18. The compensator 18 is mounted on the boom 12 a predetermined distance back from boom point 11 such that the L-

shaped arms

16 and 17 can swing the table 13 arcuately beyond and relative to boom point 11.

The main hinge of the overhead attachment 10 is provided by the pivotal connection of the main pair of arms 17 thereof at C to depending ears of a cross bracket 19. The cross bracket 19 is secured to the underside of the boom 12 to provide a pivotal connection at a fixed axis 0 about which the main pair of arms 17 swing. At the heel angle of the main pair of arms 17 a tie rod 27 is fixedly mounted in parallel relation to the cross bracket 19, axis c and the table 13. Means M for causing the main pair of arms 17 to swing about the axis c consists of a pulley block 28 attached centrally upon the tie rod 27 and a cable 29 trained over a sheave 30 at boom point 11. This cable 29 has one end secured to an eye on the block of pulley 28 and its opposite end extending back from the sheave 30 to the cab 6 of the crane 5. Within the cab 6 the cable 29 is wound about a winch (not shown) in the usual manner for winding in or paying out under the control of the crane operator.

The other pair of L-shaped arms 16 of the overhead attachment 10 comprise a stabilizer for the latter which in conjunction with the main pair of arms 17 form a parallelogram carrier P for the table 13. As previously mentioned the arms 16 are each pivotally mounted at B for swinging movement about an axis b parallel to the fixed axis c. The parallelogram carrier formed by the two pairs of L shaped

arms

16 and 17 further includes linkages in the form of

struts

23 and 24 having their ends pivotally connected as at D and E to the respective heel angles of the arms. The distance between pivotal centers D and E is comparable to the distance between the axes b and c. The length of the leg portions of arms 16 between pivots B and D are equal to that of the arms 17 between pivots C and E thus forming the parallelogram carrier P.

The foot portion 7 of each of L-

shaped arms

16 and 17 being at comparable angles, preferably 90, with respect to the leg portions thereof will likewise maintain parallel relation to each other during swinging of the carrier P. The length of the foot portions between pivots D to F and E to G is identical such that the table 13 is maintained in a horizontal disposition throughout the range of swinging movement of the parallelogram carrier P.

Referring now to FIG. 3 it will be noted that the stabilizer pair of L-shap'ed arms 16 are ofiset outwardly from the main pair of arms 17 and that the

linkage struts

23 and 24 are disposed in the space between these two pairs of arms. By this arrangement the main pair of arms 17 can swing between the lowered limit (FIG. 3) and the raised limit (FIG. 4) without obstructing each other.

Since the boom 12 is movable up and down and assumes various angular positions relative to horizontal, the compensator 18 is provided to assure horizontal disposition of the table 13 at all combined ranges of swinging movement of the boom 12 and parallelogram carrier P. To accomplish this feature the axis b about which the stabilizer arms 16 rotate is made movable relative to the fixed axis about which the main arms 17 are pivotally movable. For this reason the linkage between pivot mounts B and C is provided by strap arms 20 which are formed as a part of and under the control of the compensator 18.

Referring to FIGS. 2, 3 and 4 the stabilizer 18 comprises a cylinder or roller 22 pivotally mounted as at A on the lower structural members of the boom 12, within the radius of swing of the strap arm linkages 20. The roller 22 provides a cylindrical anchor for a pair of

cables

31 and 32 each of which is independently wound in opposite directions about the roller 22. The opposite ends of these

cables

31 and 32 are anchored on the cab 6 of the crane in the region of the pivot mount 8 for the boom 12 thereon. The

cables

31 and 32 are relatively tight such that when the boom 12 is moved up and down one cable lengthens and thus pulls at its windings on the cylindrical anchor to turn the roller 22 in one direction. This causes the other cable to be wound up upon the roller 22 as the first named cable pays out therefrom and vice versa dependent upon the up and down movement of the boom.

A pair of crank arms 21 are secured to the ends of the roller 22 for movement therewith as the cylindrical anchor is turned as aforesaid under the influence of the

cables

31 and 32. These crank arms 21 have their ends offset outwardly from the roller 22 for connection to the strap arms 20 on each side of the boom. The connection between the offset ends of crank arms 21 and the respective strap arms 20 is of the pin and slot variety. The slot is formed within and lengthwise of the strap arms 20 and the pins carried by the offset ends of the crank arms 21 extend through the slots and have enlarged heads at their outer ends.

By the foregoing arrangement the strap arms 20 will be caused to automatically change their angular disposition relative to the boom 12 during up and down movement of the latter. In other words, assuming the platform or table 13 to be held in fixed relation to the boom 12 at the position shown in FIG. 4, it will be appreciated that the table 13 would normally become tilted by any raising or lowering of the boom. However, by reason of the effect of the lengthening of one cable 31 and shortening of the other 32 during up and down movement of the boom, the linkage at strap arms 20 is caused to swing by operation of the roller 22 to compensate for variations in angular disposition of the boom. Therefore the parallelogram carrier P will automatically adjust itself independently of the normal operating facility M afforded by the pulley block 28 and man operated cable 29. The platform table 13 will thus be maintained horizontal at all times throughout the operation of the boom as Well as during manual operation of the parallelogram carrier P.

Operation With the overhead attachment 10 of the present invention various objects, articles, tools and the like carried on the table 13 can be moved between earth surface (FIGS. 1 and 3) and levels above boom point 11 as shown in FIGS. 1 and 4. The operation of the boom 12 is accomplished in the conventional manner by control of the cable 9 by winch within the cab 6. The cab 6 being supported on a turntable mount on the carriage 7 the boom can be rotated into various angles of the compass.

The parallelogram carrier P of the overhead attachment is raised and/or lowered by manipulation of the cable 29 from a Winch within the cab 6. Regardless of the angular disposition of the boom 12 relative to horizontal the compensator 18 is automatically adjusted by reason of the change of length of the

cables

31 and 32 during up and down movement of the boom. This automatically adjusts the parallelogram carrier P commensurate with the up and down movement of the boom to maintain the platform table 13 in horizontal position at all times.

Suitable tools such as grapples, claws, tongues and the like may be mounted on the platform table 13 for independent operation via cables controlled at the cab 6. The overhead attachment of the present invention thus provides a simple yet effective and efficient means for getting tools up under bridge structures, ceilings and roofs in a manner not normally feasible With conventional crane booms. Work can be accomplished above and beyond boom point of a conventional crane and the tools controlled by one man, the crane operator in the cab 6 of the crane.

While I have described the foregoing overhead attachment for the boom point of cranes in specific detail it will be appreciated by those skilled in the art that the structure may be modified, altered and/ or varied without departing from the spirit or scope of my invention therein.

I therefore desire to avail myself of all modifications, alterations and/or variations of structure as may fairly come within the purview of the appended claims.

What I claim as new and desire to protect by Letters Patent is:

1. An overhead attachment for the sheaved boom point of a crane of the type having a conventional turntable mounted cab from which a boom is winch controlled for up and down pivotal movement at the option of an operator within such cab comprising in combination:

(a) a parallelogram carrier pivotally mounted on said boom adjacent boom point thereof, said parallelogram carrier comprising:

two pairs of L-shaped arms,

a pair of struts having their ends pivotally connected to said pair of L-shaped arms between the heel angles thereof, and

a pair of linkage straps comparable in length to said pair of struts having their respective ends pivotally connected to the ends of each of said L-shaped arms at the points of pivotal mounting of the latter on said boom;

(b) a platform table supported in a horizontal position on said parallelogram carrier;

(c) means controllable from the cab of said crane and means controllable from the cab of said crane includes:

(a) a cross bar having its ends secured to one of said pairs of L-shaped arms in the region of the heel angle thereof;

(b) a block pulley secured to said cross bar substantially midway between the end thereof; and

(a) a roller journaled on said boom in the region of swing of said linkage straps;

(b) a pair of crank :arms having their inner ends secured to the ends of said roller for turning therewith; and having their outer ends pin and slot connected to said linkage straps; and

(c) a pair of cables each having one end anchored to said roller and oppositely wound about the latter and the other end of each of said pair of cables secured to the cab of said crane whereby to turn said roller and rock said crank arms and linkage straps in a direction commensurate with the up and down movement of said boom for automatically 1 adjusting said parallelogram carrier to maintain said platform table horizontal during such up and down movement of the boom.

References Cited UNITED STATES PATENTS (c) a cable having one end thereof secured to said 20 block pulley, said cable being trained around the sheave at said sheaved boom point, back around said block pulley, again over the sheave at boom point and thence to the cab of said crane for winch control therein. 25

3. The device in accordance with any one of claims 1 and 2 in which said compensator comprises;

11/1925 Clutter 214-138 2/1964 Ulinski 214-131 HUGO O. SCHULZ, Primary Examiner