Mechanism for connecting and disconnecting crane sections

Abstract

There is disclosed a crane having a base section, and an upper section separable from the base section. An anti-friction bearing on which the upper section swings relative to the base section has an outer race member connected to the base section. The inner race member of the bearing receives therein a ring on the upper section when the upper section is mounted on the base section. Opposing circumferential grooves in the ring and inner race member receive a locking ring which is expanded and contracted by a power actuator. When the ring bridges the grooves, the upper crane section is locked to the crane base section, and when the ring is contained entirely in one of the grooves, the crane upper section is released from the crane base section for separation of the sections.

Description

BACKGROUND OF THE INVENTION

Because of the size and weight of large cranes, it is often necessary to disassemble the cranes to transport them from one job site to another. The disassembly of the crane is usually accomplished by removing the upper section, or superstructure, of the crane from the base section of the crane.

Commonly, the upper section of the crane is connected to the lower section of the crane by a large number of high torque bolts which must be removed to separate the upper section of the crane from the lower section thereof. The removal of the bolts on disassembly takes considerable time and effort.

In another method of securing the upper crane section to the lower crane section, a series of cotter type joints are used wherein tangs on one section extend through the base plate of the other section. Each tang has an opening to receive a wedge member which acts as a cotter. Again, removal and replacement of a multitude of wedge members takes time and effort.

Still another method of assembly and disassembly of the upper section of a crane with the lower section thereof has been proposed in the copending United States patent application of Petrik and Dvorsky to Disconnect Mechanism For Upper Section of Crane, filed Feb. 6, 1974, U.S. Ser. No. 440,233 assigned to the same assignee as the present invention. In this latter method, an interrupted ring member on the upper crane section fits within the inner race member of the turntable bearing which is mounted in the crane base section. Interrupted surfaces on the ring member and on the inner race member, in the form of teeth, define locking surfaces when a power-operated actuator rotates the inner race member relative to the upper crane section to place the teeth of the race member in overlying relationship to the teeth of the ring member. The upper crane section is released from the lower crane section when the power-operated actuator reverses the rotation of the inner race member to a position where the teeth of the race member are in staggered relation to the teeth of the upper section ring member to permit removal of the ring member from the race member.

SUMMARY OF THE INVENTION

In the present invention, the upper crane section is detachably secured to the crane base section by means of a power-actuated locking member which, in the locking position, bridges members connected, respectively, to the upper crane section and the crane base section. One of the bridged members, however, as in the Petrik and Dvorsky application Ser. No. 440,233, is not connected rigidly to one of the sections but is rotatable with respect thereto. In the preferred form of the invention, the locking member is in the form of a ring which is received in the external groove of an annular ring member housing secured to the upper crane section. The crane turntable bearing on which the upper section of the crane swings relative to the base section has an outer race member secured to the crane base section and an inner race member into which the ring member housing of the upper crane section is received when the crane sections are assembled. A power actuator extends between the ends of the locking ring member and can selectively expand or contract the ring. A groove in the inner race member of the turntable bearing, in opposing relation to the groove in the upper section ring member when the crane sections are in assembled relation, receives a portion of the ring member when the ring member is expanded, thus bridging the grooves and locking the crane upper section to the inner race of the turntable bearing on the crane base section. When the ring member is contracted entirely into the ring member housing, the crane upper section can be separated from the crane base section.

It is therefore one object of the present invention to provide mechanism for easy locking and releasing of the crane upper section with the crane base section.

It is another object of the present invention to detachably secure the upper crane section to the crane base section by means of a power actuated locking member bridging the two sections.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a crane embodying the present invention.

FIG. 2 is a fragmentary view, in perspective, of portions of the crane upper section and the crane base section when the sections are separated.

FIG. 3 is a plan view of the mechanism, shown in lock position, connecting the crane upper section to the crane base section.

FIG. 4 is a fragmentary view, taken as the view of FIG. 3, showing the mechanism in release condition.

FIG. 5 is a view taken on the lines 5-5 of FIG. 3.

FIGS. 6, 7 and 8 are views taken as the view of FIG. 5 but showing different embodiments of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

There is shown in FIG. 1, a crane 10 having a base section 12 and an upper, or superstructure, section 14 which is mounted on the base section for rotation relative thereto. In the crane disclosed for illustrative purposes, the base section 12 is mounted on wheels 18, but it should be understood that other motive means, such as an endless crawler track, could be used instead. Alternatively, the base section could be fixed, as on a pedestal on an off-shore drilling platform or on a floating ship or barge. The base section 12 has a cab 20 for drilling the crane, or at least the base section thereof, over the highway. The upper section 14 also has a cab 22 which is for the crane operator during operation of the crane on the job site.

As shown best in FIG. 2, an outer race member 24 of a anti-friction bearing 26 is secured to the base section 12 by bolts 28. As shown best in FIG. 5, the bearing has an annular inner race member 30 which is rotatably supported on the outer race member through a circle of balls 32.

The upper section 14 of the crane has a depending ring portion, or member, 34 which has an external circumferential groove 36. The inner race member 30 has an internal circumferential groove 38 which, when the upper crane section is assembled with the base section resting on the inner race member 30 as shown in FIG. 5, is in registration with the groove 36 in the upper section ring 34.

A locking ring 40 is carried in groove 36 of ring 34. As shown best in FIGS. 2, 3 and 4, the locking ring 40 is split, at 42, and a tab 44 is secured at each end to extend inwardly therefrom. A hydraulic ram 46 is connected between the tabs and is selectively extendable and retractable to expand and contract the ring 40. The ring 34 is cut away, as at 34a, to accommodate the tabs 44 and ram 46.

The ring 40 is shown fully contracted (that is, with minimum diameter) in FIGS. 2 and 4. When contracted, the ring 40 fits entirely within the groove 36 of the upper crane section ring 34, which constitutes a housing for the locking ring 40. When the locking ring 40 is entirely within housing 34, the upper crane section 14 can be raised or lowered (as by removable jacks 48 or with an auxiliary crane or hoisting device), with ring 34 moving telescopically with respect to the inner race member 30.

When the ram 46 is extended, the ring 40 expands, increasing the diameter thereof, and the ring 40 moves into the groove 38, to bridge both grooves 36 and 38 as shown in FIG. 5. The groove 38 is wedge-shaped, with tapered upper and lower surfaces 38a and 38b. The top and bottom edges 40a and 40b of ring 40 are tapered toward the outer periphery 40c of the ring to form a wedge. When the ring 40 is expanded, the upper portion 30a of race member 30 is gripped between the ring 14a on upper section 14 and the upper surface 40a of locking member 40, as shown in FIG. 5. When the ring 40 tightly grips the inner race member 30, an adjustable link 50 is connected between the ends of the ring, adjacent to ram 46, as shown in FIG. 3. The link 50 is adjusted to hold the ring 40 and race member 30 in gripping relationship.

When ring 40 is held tightly with race member 30, as shown in FIG. 5, the upper section of the crane will be resting on, and secured tightly to, the inner race member 30. At that time, the weight of the upper crane section is transmitted through inner race member 30, the ring of balls 32, the outer race member 24, to the crane base section 12.

It should be noted that the upper section of the crane, when assembled to the base section, is rotatable about an axis A through the center of the bearing. The rotary power is supplied by a hydraulic motor (not shown) or other suitable swing drive mechanism mounted in the upper crane section. The hydraulic motor has a motor shaft 52 with a pinion 54 mounted thereon. Pinion 54 is engaged with teeth 56 on the outer periphery of the outer race 24 of bearing 26. Operation of the hydraulic motor, which is reversible, rotates the upper section of the crane in one direction and the other.

In order to release the upper crane section from the crane base section, the link 50 is removed and then the locking ring 40 is contracted by the ram 46, which constitutes a power operated actuator. After the ring 40 is contracted entirely within groove 36 of ring 34, the upper crane section can be lifted off the inner race member 34 of the bearing and transported separately from the base section to a new job site.

In the embodiment of the invention shown in FIGS. 1 to 5, the bearing is mounted in the base section of the crane, and the upper crane section is selectively locked to the inner race member thereof by means of an expandable locking ring. It will be evident from FIGS. 6, 7 and 8 that other arrangements of the bearing and locking ring can be used to releasably lock the upper crane section to the base section.

In the embodiment of FIG. 6, the bearing 126 has an inner race member 130 which is secured to the upper crane section 114 by bolts 128. The outer race member 124, which is separated from the inner race member by a ring of balls 132, has a tapered groove 138 therein. A ring 134 is secured to the crane base section 112, and has a diameter slightly greater than a necked lower portion 124a of outer race member 124. The necked portion 124a defines a shoulder 124b, with the main portion of the outer race member 124, which rests on the upper surface 134a of the ring 134 when the upper crane section is mounted on the lower crane section in assembled relation.

The ring 134, which defines a housing for a locking ring 140, has a groove 136 which is in registration with groove 138 when the crane sections are in assembled relation. The locking ring 140 is split, as ring 40, and has a ram (not shown) connected between its ends in the same manner as ram 46. When the ring is expanded by extension of the ram, the ring is held entirely within the groove 136, and the upper section of the crane can be lowered onto, or raised from, the base section. When the ram is contracted, the ring 140, which has tapered upper and lower edges like the ring 40, can be wedged into groove 138, thereby bridging the two grooves 136, 138, to force the outer race member 124 of the bearing down onto the upper surface 134a of ring 134, thereby holding the upper crane section on the base section. An adjustable link, similar to link 50, is secured between the ends of the ring 140 to hold the ring in the locking position.

In the embodiment of FIG. 7, the inner race member 230 of a bearing 226 is secured to the base section 212 by bolts 228. The outer race member 224 is supported on the inner race member by a circle of balls 232. A ring 234 on the upper section of the crane fits over the outer race member 224 when the crane sections are in assembled relation.

A tapered groove 238 in the outer periphery of the outer race member 224 is in registration with a groove 236 in ring 234 when the crane sections are in assembled relation, with the upper crane section 214 resting on the upper surface 224a of the outer race member 224. A ring 240 is housed in groove 236 of the ring-shaped housing 234. The ring 240 is split, as ring 40, and has a ram (not shown) between its ends as the ram 46. When the ram is contracted to wedge the ring 240 into groove 238, the ring will bridge the grooves 236 and 238 to force the upper crane section 214 down onto the upper surface 224a of outer race member 224, thereby locking the crane upper section to the crane base section. When the ring is expanded to fit entirely within groove 236, the upper section of the crane will be released from the base section for separation therefrom.

In the embodiment of FIG. 8, the outer race member 324 of a bearing 326 is secured to the upper section of the crane 314 by bolts 328. The inner race member 330 of the bearing is separated from the outer race member by a circle of balls 332. The inner race member has a necked portion 330a which is received around a ring 334 secured to the crane base section 312 when the crane sections are in assembled relation. A shoulder 330b, which is formed where the necked portion of the inner race member joins the main portion of the race member, seats on the upper portion 334a of the ring 334 when the crane sections are joined.

A groove 336 in the ring 334 houses a locking ring 340 which is split, as ring 40, and which has ends connected by a ram, in the same manner as ram 46 joins the ends of ring 40. A tapered groove 338 in the inner race member is in registration with groove 336 when the crane sections are assembled, and the locking ring is wedged into tapered groove 338 when the ram is extended. At that time, the locking ring will bridge the grooves and lock the crane sections together by forcing the shoulder 330b onto the upper surface 334a of the ring. An adjustable link, similar to link 50, holds the locking ring in the locking position. When the link is removed and the ram contracted, the locking ring will lie completely within groove 336. With the locking ring inside groove 336, the crane sections can be disassembled for separate transportation to a new job site.

It will be noted that in each embodiment of the invention, a socket member is defined on one of the crane sections (inner race member 30 on base section 12 in FIG. 5; ring 134 on base section 112 in FIG. 6; ring 234 on upper section 214 in FIG. 7; inner race 330 on upper section 314 in FIG. 8), and a fitting member is defined on the other crane section (ring 34 on upper section 14 in FIG. 5; outer race 124 on upper section 114 in FIG. 6; outer race 224 on base section 212 in FIG. 7; ring 334 on base section 312 in FIG. 8).

Although the best mode contemplated for carrying out the present invention has been herein shown and described, it will be apparent that modification and variation may be made without departing from what is regarded to be the subject matter of the invention.

Claims

What is claimed is:

1. In a crane having a base section and having an upper section, said crane having a bearing with relatively rotatable inner and outer portions interposed between said sections, one of said bearing portions connected to one of said sections, the improvement comprising a locking member mounted in the other of said sections and shiftable relative thereto, and a power operated actuator connected to said locking member to shift said member into and out of locking engagement with the other of said bearing portions.

2. In a crane having a base section and having an upper section, said crane having a bearing with relatively rotatable inner and outer portions interposed between said sections, said outer bearing portion connected to said base section, the improvement comprising a locking member mounted in the upper section and shiftable relative thereto, and a power actuator connected to said locking member to shift said member into and out of locking engagement with the inner bearing portion.

3. In a crane having a base section and having an upper section, said crane having an antifriction bearing with inner and outer race rings interposed between said sections, said outer race ring connected to said base section, the improvement comprising a locking member mounted in the upper section and shiftable relative thereto, and a power actuator connected to said locking member to shift said member into and out of locking engagement with the inner race ring.

4. In a crane having a base section and having an upper section with a depending ring, said crane having an antifriction bearing with inner and outer race rings interposed between said sections, said inner race ring receivable over said depending ring and said outer race ring connected to said base section, the improvement comprising, means defining opposing grooves in said depending ring and said inner race ring, a locking ring received in said grooves, and a power actuator to expand and contract said locking ring from a position bridging both grooves to a position within one of said opposing grooves.

5. In a crane having a base section and having an upper section with a depending ring, said crane having an antifriction bearing surrounding said depending ring, said antifriction bearing having an inner ring surrounding said upper section depending ring and having an outer race connected to said base section, a groove in said upper section depending ring and a groove in said antifriction bearing inner race, said grooves in registration when the upper section of the crane is mounted on the base section, a locking ring mounted in the groove of the upper section depending ring, and a power actuator connected to said locking ring to expand said ring to bridge both grooves and to contract said ring into the groove of the upper section depending ring.

6. In a crane having a base section and having an upper section, said crane having a bearing with relatively rotatable inner and outer race rings interposed between said sections, one of said race rings connected to one of said sections, the improvement comprising a locking ring mounted in the other of said sections for expansion and contraction relative thereto, and a power operated actuator connected between the ends of said locking ring to change the diameter thereof for locking engagement with the other of said race rings.

7. In a crane having a base section and having an upper section removably mounted on the base section, said crane having a bearing with relatively rotatable inner and outer race rings interposed between said sections, one of said race rings connected to one of said sections, the improvement comprising a peripheral groove in the other of said sections and in the other of said race rings, said peripheral grooves being in alignment when the upper section of the crane is mounted on the base section of the crane, a locking ring mounted in one of said peripheral grooves, and a power actuator connected between the ends of said locking ring to alter the diameter of the locking ring to bring the locking ring into bridging relationship with both of the grooves.

8. In a crane having a base section and having an upper section, said upper section having a depending portion and said crane having a bearing with relatively rotatable inner and outer portions interposed between the base section and the depending portion of said upper section, said outer bearing portion connected to said base section, the improvement comprising a peripheral groove encircling the inner bearing portion and a peripheral groove encircling the depending portion of said upper section, said peripheral grooves being in alignment when the upper section of the crane is mounted on the base section of the crane, a locking ring mounted in one of said peripheral grooves, and a power actuator connected between the ends of said locking ring to alter the diameter of the locking ring to bring the ring into bridging relationship with both of the grooves and exert a locking action between, and completely around, the inner bearing portion and the depending portion of said upper section.