US 3709543 A
A crane for loading and unloading container ships and for otherwise handling large containers is equipped with two elongated lifting frames suspended from the cables or ropes of two hoists in such a manner that the frames may be longitudinally aligned in end-to-end relationship. Each frame is equipped to be lengthened in a direction away from the other frame by 5 ft. to 20 ft. of effective length, and the frames may be rigidly coupled so that the frame, singly or jointly, may carry any container having a length of 15, 20, 30, 35, or 40 feet.
Description (OCR text may contain errors)
United States Patent 1 Tax et al.
 LOADING CRANE FOR SHIPPING CONTAINERS OF DIFFERENT SIZE  Inventors: Hans Tax; Rudiger Franke, both of Munich, Germany  Assignee: said Tax, by said Franke 22 Filed: on. 19, 1970  Appl. No.: 82,106
 U.S. Cl ..294/8l SF, 294/67 DA  Int. Cl ..B66c l/00  Field of Search....294/8l SF, 67 R, 67 DA, 86 R  References Cited UNITED STATES PATENTS 3,536,351 10/1970 Zweifel et al. ..294/81 R 51 Jan.9, 1973 Primary Examiner-Harvey C. l-lornsby Attorney-Kelman & Berman  ABSTRACT A crane for loading and unloading container ships and for otherwise handling large containers is equipped with two elongated lifting frames suspended from the cables or ropes of two hoists in such a manner that the frames may be longitudinally aligned in end-to-end relationship. Each frame is equipped to be lengthened in a direction away from the other frame by 5 ft. to 20 ft. of effective length, and the frames may be rigidly coupled so that the frame, singly or jointly, may carry any container having a length of 15, 20, 30, 35, or 40 feet.
15 Claims, 6 Drawing Figures PATENTEUJAN 9 I973 SHEET 2 0F 4 lllllhllll Pmammm ems 3.709.543
SHEEI k U? 4 Fig.6
LOADING CRANE FOR SHIPPING CONTAINERS OF DIFFERENT SIZE This invention relates to the handling of large containers designed for transportation by means of containerships, and particularly to a loading crane for lifting and lowering such containers.
More specifically, the invention is concerned with an improvement in the known container loading crane which has two elongated, normally horizontally extending lifting frames arranged for being coupled in end-toend relationship, and suspended from the tension elements, such as ropes or cables, of respective hoists. The known crane permits the simultaneous lifting and lowering of two containers which match the dimensions of the two identical lifting frames. The two frames are coupled to each other so that the containers suspended therefrom cannot collide and damage each other, but the frames are capable of moving angularly about the coupling relative to each other.
The known crane can handle only containers of one standard size.
It is also known to equip container loading cranes with lifting frames whose length may be varied to some extent. The weight, bulk, and complexicity of the mechanism needed for increasing the length of a frame while maintaining adequate regidity and stability do not increase linearily with the increment desired, and it is impractical to provide a lifting frame with a conventional lengthening mechanism permitting a length increase of 100 percent or more over the base or minimum length of the frame.
The primary object of the invention is the provision of a lifting crane for containers of the type described which can handle individual containers which differ in length by lOO percent or more, and also capable of simultaneously handling two containers of the same size or of different sizes.
With this object and others in view, as will hereinafter become apparent, the crane of the invention is equipped with two lifting frames which are elongated and normally horizontal, container engaging locks on the frames for suspending a container from each frame, and a hoist arrangement including two sets of tension members respectively engaging the frames for raising and lowering the same. A coupling may couple the frames to each other in end-to-end relationship. This much is common to this invention and to the prior art.
However, the lifting frames of this invention are each provided with lengthening devices which permit the length of the frame to be increased in a direction away from the other frame, and the coupling mechanism permits the frames to be secured to each other in a rigidly fixed spatial relationship in which the frames are longitudinally aligned.
Other features and the attendant advantages of this invention will readily be appreciated as the same becomes better understood by reference to the following detailed description of a preferred embodiment when considered in connection with the appended drawing in which:
FIG. 1 shows a container loading crane of the invention and a load suspended therefrom in fragmentary side elevation;
FIG. 2 illustrates the apparatus of FIG. 2 in top plan view;
FIG. 3 shows the apparatus of FIG. 2 in its cooperation with a different suspended load;
FIG. 4 shows a coupling largely obscured in the view of FIG. 1 on a larger scale;
FIG. 5 shows the crane in fragmentary front elevation; and
FIG. 6 shows a portion of the apparatus of FIG. 5 in top plan view.
Referring now to the drawing in detail, and initially to FIGS. 1 and 2, there is seen a shipping container 10,35 ft. long and of standard width and height, which is suspended from two lifting frames 12,12. The frames are mirror images of each other except for certain details which will presently become evident. Elements associated with the frame 12' have been given reference numerals differing by a prime from the reference numerals of corresponding elements associated with the frame 12, and will not be discussed separately in most instances, the description being limited largely to the frame 12 and associated devices.
The frame 12 has the shape of an elongated, horizontal rectangle and is longitudinally aligned with the frame 12' in abutting end-to-end relationship. The portion 14 of the frame 12 near the frame 12' accomodates coupling devices presently to be described, and its height is about twice that of the free end portion 16 of the frame.
The longitudinal side members of the frame 12 receive respective beams 18 in telescoping engagement. Each beam is attached to the free end of a piston rod 15 of a double acting hydraulic jack 17 and is held in the rectracted position by the associated jack. The corresponding beams 18' of the frame 12' are shown extended so that the effective length of the frame 12 is 15 ft., that of the frame 12, 20 ft., and their combined length 35 ft. to match the container 10.
The frame 12 is suspended from two longitudinally spaced groups 19,21 of hoisting cables trained over respective pairs of sheaves 23,20 on the frame 12 and over a cable drum or a winch, not seen in FIGS. 1 and 2. The sheaves 23 are located near the free end of the frame 12, and the sheaves 20 approximately at the center of its length. With the beams 18' extended, the sheaves 20,23 are approximately equidistant from the ends of the lengthened frame 12' and symmetrical to its center.
The four comers of the frame 12 carry twist locks 26,28 for engagement with sockets on suspended containers. The two locks 26 are mounted on the free ends of the extension beams 18, and the locks 28, inoperative in the condition of the apparatus seen in FIGS. 1 and 2, are retracted so that the container 10 is suspended by its four comers from the beams 18,18 by the locks 26,26. The locks are not shown in detail in the drawing since they are not themselves part of this Invention.
The rigid connection between the frames 12,12 necessary for suspending a single container from both frames is provided by a coupling mechanism having respective sections 32,33 on the frames 12,12 only outlined in FIG. I, omitted entirely from FIGS. 2 and 3 for the sake of clarity, and better seen in FIG. 4. The electric and hydraulic power and control lines for the devices on the frame 12 are combined in a cable 30 which is coiled in a receptacle 29 when the frame 12 is raised from the illustrated position by the cables 19,21.
Since each frame 12,12 may be made either or ft. long, it is apparent that the crane, only seen in FIGS. 1 and 2 to the extent necessary for an understanding of the invention, can handle single containers 30,35, or 40 ft. long, and one or two containers 15 or 20 ft. long. When the frames 12,12 simultaneously carry respective containers, a rigid connection between the containers is not needed, and end-to-end abutment of the frames is to be avoided if it is desired to lift two containers simultaneously from two compartments of a ship separated by a bulkhead.
FIG. 3 shows the frames 12,12 respectively carrying 20 ft. containers and coupled in spaced end-to-end relationship by devices which are also seen in FIGS. 1 and 2, though less clearly. A recess in the top of the frame portion 14 which is open toward the frame 12 accomodates a slide 37 attached to the piston rod 38 of a hydraulic jack 39 which may shift the slide 37 horizontally toward and away from the frame 12. Sockets 36 spaced on the slide 37 transversely of its direction of movement are open toward each other and shaped for conforming engagement by latches 48 mounted on the long arms of respective rockers 40 and having each the shape of an isoceles right triangle in horizontal section.
The rockers are pivoted to the frame 12' on vertical pins 42 in a recess closely similar to that which receives the slide 37 in the frame 12. The short arm of each rocker 40' is hinged to a small hydraulic jack 44 pivotally mounted in the recess of the frame 12 for swinging the associated rocker 40 between the fully extended position of FIG. 3 in which the latches 48 are received in the sockets 36, and the rockers 40 are about parallel and the retracted position of FIG. 2 in which the rockers 40 are entirely withdrawn within the frame 12. A resilient mounting pad 50 is interposed between each latch 48' and the associated free end of an arm 40.
The two coupling mechanisms arranged on respective sides of the frames 12,12 are represented by the showing of FIG. 4 which illustrates one rigid coupling mechanism 32,33, the other one being substantially identical.
The section 32 of the coupling mechanism which is mounted on the frame 12 consists of an internally threaded disc 52 rotatable in a friction lining 31 which impedes, but does not prevent rotation of the: disc, and of an electric gear motor, not shown, which is coupled to a partly threaded spindle 50 for rotating the same, as indicated by a curved arrow. The spindle 50 carries a fixed collar 54 at the end of its threads near the motor.
The section 33 of the coupling mechanism includes a conical guide funnel 56 coaxial with the spindle S0 and leading to an internally threaded disc 58 pivotally mounted on the frame 12 in bearings 46.
As is evident from FIG. 3, the two containers 10 may be lowered into two compartments of a ship on either side of a bulkhead. The containers remain coupled to each other by the rockers 40 and the sockets 36 until they are separated by the bulkhead and can no longer damage each other by colliding. The rocker arms are then retracted into the position seen in FIG. 2, and the containers 10 may be brought to rest in the respective compartments. The width of the gap between the containers and their positions relative to the bulkhead may be adjusted by shifting the slide 37. If
it is desired to lock the frames 12,12 rigidly to each other to make them ready for carrying a single large container, the rockers 40 and the slide 37 are operated to engage the spindle 50 on the frame 12 with the conical guides 56 on the frame 12' until the free ends of the spindles 50 touch the discs 58.
When the spindles 50 are then turned by the nonillustrated associated motors, the threads on the spindles 50 engage those in the discs 58', such engagement being facilitated by thepivotal mounting of the discs 58 which compensates for slight misalignment. The discs 52 stand still in the associated friction linings 31 until axially engaged by the collars 54, and the two frames 12,12 are drawn toward each other by the spindle 50 only after the spindle is safely engaged in the disc 58'. As is shown in FIGS. 1 and 2, the frames 12, 12 ultimately abut against each other and cannot pivot about a transverse horizontal axis under the weight of the container 10 applied to the operative locks 26, 26, the locks 28, 28' being inoperative.
A preferred manner of suspending the frames 12,12 from the trolley 59 of an associated crane is shown in FIGS. 5 and 6, the trolley and the frames 12,12 being omitted from FIG. 6 for a clearer representation of the hoists.
Referring initially to FIG. 5, there is seen the group 19 of hoisting cables 19a,19b which are trained over the sheaves 23 on the frame 12. One end of each cable 19a,19b is fastened to a cable drum 64 on the trolley 59, and the other ends of the two cables are attached to parts of a beam 62 which are equidistant from a pivot 63, the beam being suspended from the pivot. Helical tension springs, not themselves visible, are interposed in respective housings a,60b between the cable ends and the beam 62.
The drum 64 is operated by an electric drive unit 65, as is shown in FIG. 6, and accomodates not only the cables of the group 19, but also the cables 21a,21b of the cable group 21 which connect the sheaves 20 with another beam pivotally suspended from the trolley 59 in the manner shown in FIG. 5. A winch 64' having its separate drive unit 65 operates the cables for the frame 12 as described with reference to the cable groups 19,12. The winches or cable drums 64,64 are coaxially mounted on the trolley 59 and may be coupled by means of an electromagnetic clutch 70.
Each cable group 19,2l,19',2l' provides a V-suspension for the associated frames 12,12 and thus prevents oscillations of the container 10 in the plane of FIG. 5 on the beam 62. Oscillation of the beam itself is limited and clamped by a telescoping shock absorber 66 interposed between one end of the beam 62 and the trolley 59, andanalogous shock absorbers 67 are provided for the other three beams. The springs in the housings 60a,60b for the cable group 19, and the corresponding springs in the housings 61a, 61b for the cable group 21 tend to equalize the loads supported by the several cables. The springs are chosen for equal spring constants.
The spring arrangement has been found effective in preventing overloading of individual hoisting cables by containers whose center of gravity is relatively far from the geometrical center, and for operation of each frame with its extension beams 18,18 retracted so that the sheaves 20,23 are not symmetrical relative to the frame center, or for operation under the conditions of FIGS. 1
and 2, when one frame is extended while the other is contracted to its minimum length.
When the two frames 12,12 support respective individual containers, as shown in FIG. 3, the rockers 40 provide a somewhat flexible coupling because of their own resiliency and because of the resiliency of the pads 50. If needed, the frames 12,12 may be given additional, limited freedom of relative movement by loosening the engagement of the sockets 36 by the latches 48. This is convenient, and may sometimes be necessary in simultaneously setting two containers into different compartments of a ship, as mentioned above.
What is claimed is:
1. In a container loading crane including two elongated, normally horizontal frames, container engaging means on each frame for suspending a container from said frame, hoist means including two sets of tension members respectively engaging said frames for raising and lowering the same, and coupling means releasably coupling the frames in end-to-end relationship, the improvement which permits a single container to be lifted by said two frames comprises:
a. lengthening means for increasing the length of each frame in a direction away from the other frame,
. said coupling means including means for preventing pivoting movement of the coupled frames about a horizontal axis transverse to the common direction of elongation of said frames when a single container is suspended simultaneously from said two frames,
0. said container engaging means including locking means at the two longitudinal ends of each frame, the locking means on the end of each frame adjacent the other frame being vertically movable between an operative and an inoperative position to prevent damage to the container, while permitting the container to be supported only by the locking means at the opposed ends of the two frames.
2. In a crane as set forth in claim 1, said coupling means further including securing means for securing said frames to each other in longitudinally spaced relationship while permitting limited relative movement of the secured frames.
3. In a crane as set forth in claim 1, said means for preventing pivoting movement including engaged abutment means on said coupled frames.
4. In a crane as set forth in claim 1, said means for preventing pivoting movement including means for holding said frames in longitudinally abutting engagement.
5. In a crane as set forth in claim 1, said lengthening means including means for increasing the length of each frame by a fixed amount, whereby each frame may have a first length or a second length greater than said first length by said fixed amount.
6. In a crane as set forth in claim 5, each set of tension members including two groups of tension members, two sheave arrangements longitudinally spaced on each frame, said sheave arrangement being substantially equidistant from the longitudinal center of each frame in opposite directions when said frame has said second length. l
7. In a crane as set forth in claim 6, one of said sheave arrangements being closely adjacent a longitudinal end of said frame when said frame has said first length.
8. In a crane as set forth in claim 2, said securing means including two rocker arms pivotally mounted on one of said frames, latch means on each arm, two socket members on the other frame respectively engageable by said latch means for coupling said frames to each other, and actuating means for pivoting said rocker members toward and away from engagement of said latch means with said sockets.
9. In a crane as set forth in claim 5, said latch means including a latch member tapering toward the associated socket member, said socket member being formed with a recess shaped for conforming engagement by said latch member.
10. In a crane as set forth in claim 9, resilient mounting means interposed between each latch member and the associated rocker arm.
11. In a crane as set forth in claim 8, moving means for moving said socket members longitudinally on said other frame.
12. In a crane as set forth in claim 1, said means for preventing pivoting movement including a first, externally threaded coupling member on one of said frames and a second, internally threaded coupling member on the other frame engageable with said first coupling member, one of said coupling members being mounted for rotation on the associated frame, securing means securing the other coupling member against rotation on the frame associated therewith.
13. In a crane as set forth in claim 8, said one coupling member being said first coupling member, an internally threaded mounting member rotatably secured on said one frame and threadedly receiving said first coupling member, friction means impeding rotation of said mounting member, an abutment on said first coupling member engageable with said mounting member by rotation of the coupling member, and pivot means securing said second coupling member against rotation on said other frame while permitting pivoting movement of the second coupling member. I
14. In a crane as set forth in claim 1, said hoist means including a spring member arranged in series with each of said tension members, the spring constants of said spring members being equal.
15. In a crane as set forth in claim 1, two sheaves longitudinally spaced on each frame, each set of tension members including two tension members respectively trained over said sheaves, said hoist means further including two drum members, said tension members being secured to said drum members respectively, two drive means connected to said drum members respectively for rotating the same and for thereby lengthening and shortening said tension members, and coupling means for coupling said drum members to each other for joint rotation.
Patent No. 3,709,543 Dated January 9, 1973 Inventor(s) HANS TAX ET AL It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
In the title page, after line 451.7 insert [597 Foreign Application Priority Data October 29, 1969 Germany P 19 54 474.2
Signed and sealed this 29th day of May 1973.
EDWARD M.FLETCHER,JR. ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents I FORM P"5 (10-59) I uscoMM-Dc wan-pas ".5. GOVERNMENT PRINTING OFFICE: l9! O-366-334. v