US3109542A

US3109542A - Stabilizers for cranes and the like

Info

Publication number: US3109542A
Application number: US184028A
Authority: US
Inventors: George C Noll; Joseph D Zook
Original assignee: Thew Shovel Co
Current assignee: Thew Shovel Co
Priority date: 1962-04-02
Filing date: 1962-04-02
Publication date: 1963-11-05
Anticipated expiration: 1980-11-05
Also published as: GB1015905A

Description

Nov. 5, 1963 G. c. NOLL ETAL STABILIZERS FOR CRANES AND THE LIKE Filed April 2, 1962 FIG I INVENTOR. GEORGE C. NOLL 8 BY JOSEPH D. ZOOK FIG 3 ATTORNEYS United States Patent 3,109,542 STABlLlZERS FQR CRANES AND THE LIKE George C. Noll, Elyria, and Joseph 1). Zach, Uberlin, ()hio, assignors to The Thew Shovel Company, Lorain, Ohio, a corporation of Ohio FilcdApr. 2, 1962, Ser. No. 184,028 12 Claims. (Cl. 212-59) This invention relates generally, as indicated, to stabilizers for cranes and the like and more particularly to releasable stabilizers to preclude excessive tipping of the revolving superstructure with respect to the carrier to reduce excessive loads on the superstructure pivot.

With the continued striving for cranes, shovels, and the like having greater reach and lifting capacities, longer and sturdier crane booms are being employed. However, such longer booms present an erection problem in that it is difficult to lift from the ground boom structures having a length of, for example, 300 feet. Cranes such as tower cranes or gantry cranes mounted on rails adjacent a building site or the like cannot generally be erected from the ground, but must be assembled in a working condition. When booms are elevated from the ground to a working position, an added, often destructive, load is placed upon the superstructure pivot bearing which results in the tendency of the superstructure to tip forward in the direction of the boom. When erecting such long booms from the ground, it has been found that additional stabilization is required due to the long radius or moment arm of the weight being lifted.

It is accordingly a principal object of the present invention to provide a stabilizer for cranes and the like to enable long heavy booms to be erected from the ground without damaging the carrier-superstructure bearings and connections or to lift larger live loads in a static position of superstructure.

It is another main object to provide a stabilizer for cranes and the like which will reduce the moment in the carrier frame during such boom erection, for example.

It is another object to provide stabilizer means for cranes and the like which will overcome added loads on the superstructure pivot thus reducing bearing wear when excessive loads are being lifted by the crane.

Other objects and advantages of the present invention will become apparent as the following description proceeds.

To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims, the following description and the annexed drawing setting forth in detail certain illustrative embodiments of the invention, these being indicative, however, of but a few of the various ways in which the principle of the invention may be employed.

In said annexed drawing:

FIG. 1 is a side elevation partially broken away of a crane having a superstructure-carrier stabilizer in accordance with the present invention;

FIG. 2 is a similar side elevation of a crane showing another form of the present invention; and

FIG. 3 is a similar side elevation showing yet a further embodiment of the present invention.

Referring now to the annexed drawing and more particlarly to the embodiment of the invention illustrated in FIG. 1, there is shown a crane which comprises a re volving superstructure 1 which is mounted by means of a turntable 2 through a bearing connection 3 on the platform frame 4 of a carrier 5. The revolving superstructure 1 includes an internal combustion engine mounted as at 7 driving t.e hoist drums for lifting and lowering loads and additionally for raising and lowering boom $399,542 Patented Nov. 5, 1963 8 pivoted at foot 9 to the frame of the revolving superstructure. The boom is raised and lowered by means of reeving cables indicated diagrammatically at It} which pass over sheaves ll mounted on the top of a gantry 12. The gantry 12 may, for example, be a folding mast type gantry pivoted adjacent the boom foot 9 which can be pivoted to lie along the boom 3 in a folded or traveling position. The revolving superstructure 1 includes an operators cab 13 at the front end thereof and a removable counterweight 14 at the rear end, such counterweight being sufficient to balance the weight of the boom and load in the normal operating angle of inclination and radius ranges of the boom 3.

The revolving superstructure 1 is mounted on the turntable 2 which is in turn connected through bearing 3 to the bed of carrier 5. Such carrier, as illustrated, may be a heavy framed, rubber-tired carrier which includes a prime mover i6 and a forward operators cab 17. As illustrated, the carrier 5 is supported on four axles 18, 19, 2t"? and 21. The wheels of the two rear axles 2% and 2 1 may carry two tires each so that the carrier will be supported on a total of twelve tires 22. The rear axles 2d and 21 may be driven from the prime mover so that a carrier is, in effect, an 8 x 4 carrier. The heavy bed frame 4 of the carrier 5- is provided with two

outrigger boxes

23 and 24, each of which houses a pair of outrigger beams which can be extended by a hydraulic motor outwardly and downwardly to engage the ground as shown by the

beams

25 and 26, extended from the outrigger box 24- at the rear of the carrier 5. Plates 27 are pivotally mounted at the ends of the beams to engage the ground 28 laterally of the frame 4 to increase the stability of the machine by increasing the size of the supporting base. Reference may be had to the copending application of Spencer Bowman, assigned to The Thew Shovel Company of Lorain, Ohio, entitled Cutriggers for lower Shovels, Cranes or the Like, Serial No. 803,- 597, filed April 2, 1959, now Pat. No. 3,021,015, for a more complete disclosure of Outriggers that may preferably be employed with cranes and the like of the present invention.

When erecting extremely long and heavy booms as those disclosed, for example, in the copending application of John 1. Jones et al., Serial No. 86,166, entitled Crane, filed January 31, 1961, the boom 8 will generally extend along the ground and be supported thereon with the turntable facing to the rear of the carrier and the boom pivoted to the foot 9. The force applied through lifting cable it required to overcome the inertia of the boom resting on the ground will be substantial in View of the extremely long moment arm, the distance between the center of gravity of the boom and the center of the bearing 3, and this force will cause the superstructure l and the turntable 2 to tip forward at the front edge of the turntable bed thus creating a downward load on the bearing connection 3 at the front end thereof. Whereas a downward load will be produced at the forward edge of the bearing, the same tipping effect will cause the rear end of the turntable to lift off the mounting. The added loads provided required to overcome the static inertia of the boom then produce excessive loading and wear on the bearing 3 and its connections both with the revolving superstructure 1 and the bed frame 4 of the carrier 5. Also the added load tends to tip the carrier 5 about the pivot provided by the contact of the tire 22 with the ground at the rear of the carrier as shown at Sit, or about the plates 27 with the rear outriggers extended. The tipping condition is considered to exist when all tires on one or more wheels leave the supporting surface 28.

In the FIG. 1 embodiment, to preclude both the forward tipping of the superstructure l in the direction of the boom and to reduce the resulting bending moments in the carrier frame 4 resulting from the existence of a tipping condition, there is provided a rigid strut connection between the revolving superstructure and such carrier frame as indicated generally at 32. In this embodiment, such strut takes the form of a link 33 pin-connected as at 34 and 35 to the revolving superstructure 1 and the carrier frame 4, respectively. A pair of cars 36 may be provided on the carrier frame through whichthe link 33 may be pin-connected. The link 3-3 may be more or less permanently connected to the revolving superstructure 1 by the pin 34 and the pin 35 can readily be driven out of engagement so that the link 33 may be pivoted about the pin 34 and latched in a substantially horizontal position to clear the cars 36. Thus a readily releasable rigid strut is provided extending from the superstructure to the carrier frame which is operative to preclude the aforesaid forward tipping of the superstructure in the direction of the boom. Accordingly, the machine can then lift overloads in fixed planes such as when raising extremely long and heavy booms and this prevents overloading of the carrier-tosuperstructure bearing 3 and its connections. The link also reduces the bending moment in the carrier frame 4 by transferring this tipping force to the carrier frame at a point substantially closer to the middle of the frame 4 than is the position of the bearing 3. Further to stabilize the carrier 5, the front end thereof is provided with a hook 40 which removably supports a counterweight 41. The counterweight then precludes any tipping of the carrier which would tend to lift the front tires from the supporting surface 28. It will be understood that the links 33 will be provided on each side of the revolving superstructure rigidly connecting such superstructure to the frame 4 of the carrier in that these links will preclude the excessive loading of the bearing 3. It is noted that the

outrigger beams

25 and 26 at the rear of the carrier frame may be extended as shown further to stabilize the supporting base for the machine when lifting overloads.

Referring now to the embodiment of the invention illustrated in FIG. 2, parts which are identical in form to the parts of the FIG. 1 embodiment are labeled by the same reference numeral. In the FIG. 2 embodiment, a revolving superstructure 50 is mounted on a turntable 2 con nected bybear-ing 3 to the bed frame 4 of the carrier 5 which is identical in form to the carrier 5 of the FIG. 1 embodiment. The boom hoist cable is trained about sheaves Slat the peak of a back hitch gantry shown generally at 52. Such back hitch gantry extends over the back of the revolving superstructure and may be elevated to a working position or lowered to a traveling position. This gantry may comprise telescopic back struts 53 and pivotally' mounted frame 54 connected to such struts by a peak pivot axle 55 which also mounts the sheaves 51. It will be understood that the gantry, shown in its working position, is greatly foreshortened and reference may be had to the copending application of George C. Noll and Paul E. Wesebau-m, Serial No. 103,045, filed April '14, 1961, entitled Back Hitch Gantry for a more complete disclosure of a gantry that may be employed with the present invention.

To reduce the excessive loading on the bearing 3 caused by the tendency of the revolving superstructure to tip forwardly in the direction of the boom 8, there is provided in this embodiment a releasable strut 57 which may be comprised of cable sections 58 and 59, the two sections being interconnected by a turnbuckle or the like 60 and the opposite ends of the cable thus formed are connected to the gantry peak axle 55 and to a pin 61 inserted through aligned pin holes in plates 62 welded between a bedframe. 4 and the cab :17 of the carrier 5. The turnbuckle may be employed to maintan the proper tension in the cable and to compensate for pin-connection 'wear. The pin 61 may readily be driven from the plates tween the gantry and the frame of the carrier, the forward tipping of the revolving superstructure is precluded and accordingly overloading of the carrier-to-superstructure bearing is prevented. It is noted that in this embodiment, the bending moments in the carrier frame 4 will be reduced even more than in the FIG. 1 embodiment since the connection afforded by the pin 61 and plates 62 is substantially forward on the carrier 5. The counterweight 41 may be connected to the carrier by means of the supporting hook 449 further to stabilize the carrier and also the

outrigger beams

25 and 26 may be extended thus increasing the size of the supporting base of the machine and precluding the existence of a tipping condition.

In the embodiments of the invention shown in FIGS. 1 and 2, the

struts

33 and 57 will be under tension during overloading. In the embodiment. of the invention illustrated in FIG. 3, there is provided a compression block which may be positioned between the front of the superstructure frame and the top of the bed frame 4 of the carrier 5. Compression block 70 then serves to support and shim up the front end of the superstructure frame to preclude the forward tipping or the tipping in the direction of the boom. The compression strut 70 may be comprised of a link pivoted to the boom foot 9 which may be driven into engagement against a wear plate or the like 71 secured to the bed frame 4 of the carrier 5. One or more of such compression struts maybe provided and such may be driven into wedged engagement and easily released simply by knocking them to the right as seen in FIG. 3, and, of course, such compression struts can be pinned out of the way during operation of the machine. It will beunderstood that all of the connections between the revolving end of the revolving superstructure frame and the frame 7 of the carrier, the compression struts may extend from the revolving superstructure frame directly to the supporting surface or ground 28. In either manner, the front end of the revolving superstructure will be precluded from tip pin forward or in the direction of the boom. The revolving superstructure 1 and the carrier 5 in the FIG. 3 embodiment is otherwise identical in form to the crane disclosed in FIG. 1.

It can now be seen that there is provided a simplified means to overcome added loads on the superstructure carrier bearing pivot connection which may occur when lifting overloads in a fixed plane such as the raising of extremely long and heavy booms to erect a crane to operating position. When a boom is inoperating position, the counterweight 14 will tend to balance the weight of the boom and load about the axis of the pivot pro vided by the bearing 3. The addition of the counterweight 41 to the front bumper of the carrier by means of the hook 40 further stabilizes the carrier and precludes existence of a tipping condition. Since the counterweight added to the front end of the vehicle also would increase the load on the bearing 3 by increasing the separating force or load on the bearing at the rear of the revolving superstructure, it can readily be seen that the releasable struts provided in the three embodiments of the present invention clearly overcome these otherwise deleteriousexcessive loads. Not only do the struts prevent overloading of the carrier-to-superstructure bearings and connections, but additonally reduce the bending moment in the carrier frame which results from the tendency of the front end to lift. 7

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims or the equivalent of such be employed. a

We, therefore, particularly point out and distinctly claim as our invention:

1. In a power shovel, crane or like machine combination including a carrier frame, revolving superstructure supported on said carrier frame by a carrier-superstructure bearing, an elongated boom pivoted to the forward end of said superstructure; a stabilizer comprising releasable strut means extending from said superstructure to said carrier frame operative to preclude forward tipping of said superstructure with respect to said carrier frame in the direction of said boom to prevent excessive loading of said bearing.

2 The combination set forth in claim 1 wherein said strut means comprises a compression strut extending from a forward end of said superstructure adjacent said boom to said carrier frame.

3. The combination set forth in claim 1 wherein said revolving superstructure includes upwardly extending gantry means adapted to support said boom through suitable reeving, said strut means comprising a flexible link of inextensible length extending from said carrier frame to the peak of said gantry.

4. The combination set forth in claim 1 wherein said strut means comprises a flexible link of inextensible length extending from said carrier to the rear end of said superstructure.

5. The combination set forth in claim 1 wherein said strut means comprises a rigid link pin-connected to said carrier frame and the rear end of said superstructure.

6. The combination set forth in claim 1 wherein said releasable strut means comprises a tension link extending from the rear of said superstructure to said carrier frame, said strut means being connected to said carrier frame on the opposite side of said turntable from said boom, thereby to reduce bending moments in said carrier frame resulting from the tendency of the superstructure to tip forward during over loading, and counterweight means mounted on said carrier frame at the opposite end of said carrier frame from said revolving superstructure.

7. A crane comprising a carrier frame, a revolving superstructure supported on said carrier frame by a carrier-superstructure bearing, an elongated boom pivoted to the forward end of said superstructure, and releasable strut stabilizing means extending from said superstructure to said carrier frame operative to preclude forward tipping of said superstructure relative to said carrier frame in the direction of said boom to prevent excessive loading of said bearing.

8. A crane as set forth in claim 7 wherein said stabilizer means comprises a compression strut extending from the forward end of said superstructure adjacent said boom to said carrier frame.

9. A crane as set forth in claim 7 wherein said stabilizer means comprises a rigid link pin-connected to said carrier frame and the rear end of said revolving superstructure.

10. A crane as set forth in claim 7 wherein said stabilizer means comprises a flexible link of substantially inextensible length extending from said carrier frame to the rear end of said superstructure.

11. A crane as set forth in claim 7 wherein said revolving superstructure includes an upwardly extending gantry adapted to support said boom through suitable reeving, said stabilizer means comprising a flexible link of substantially inextensible length extending from said carrier frame to the peak of said gantry.

12. A crane as set forth in claim 7 including means on said carrier frame at the end thereof opposite said revolving superstructure, adapted to support a removable counterweight.

References Cited in the tile of this patent UNITED STATES PATENTS 2,167,026 Hatch July 25, 1939 2,360,654 Day Oct. 17, 1944 2,820,556 Davis Jan. 21, 1958