US3764021A

US3764021A - Rotary crane

Info

Publication number: US3764021A
Application number: US00216592A
Authority: US
Inventors: H Scheuerpflug
Original assignee: Individual
Current assignee: Individual
Priority date: 1971-01-14
Filing date: 1972-01-10
Publication date: 1973-10-09
Anticipated expiration: 1990-10-09
Also published as: DE2101514A1; GB1313828A; FR2121781A1; FR2121781B1

Abstract

In a crane wherein an upper carriage is rotatably supported on a base and an elevated boom has at least one supporting strut deriving a vertical reference from a point offset from the axis of crane rotation, the invention provides at such reference a member slidably guided in the carriage and having roller contact with the base. The arrangement is such as to enable boom loading to be sustained directly by the base, regardless of the rotary position of the crane and regardless of such unevenness as may exist in the path of roller contact about the rotary axis of the crane.

Description

United States Patent [1 1 Scheuerpflug ROTARY CRANE [75] Inventor: Hans Scheuerpflug, Bad

Mingolsheim, Germany [73] Assignee: Firma Johannes Fuchs, Ditzingen,

Baden-Wurttemberg, Germany 22 Filed: Jan. 10, 1972 21 Appl. No.: 216,592

[30] Foreign Application Priority Data 6/1877 Kirkam 212/47 Oct. 9, 1973 FOREIGN PATENTS OR APPLICATIONS 2,279 9/1856 Great Britain 212166 894,681 4/1962 Great Britain 212/35 Primary Examiner-Even C. Blunk Assistant Examiner-H. Lane Attorney-Nichol M. Sandoe et a1..

[57] ABSTRACT In a crane wherein an upper carriage is rotatably supported on a base and an elevated boom has at least one supporting strut deriving a vertical reference from a point offset from the axis-of crane rotation, the invention provides at such reference a member slidably guided in the carriage and having roller contact with the base. The arrangement is such as to enable boom loading to be sustained directly by the base, regardless of the rotary position of the crane and regardless of such unevenness as may exist in the path of roller contact about the rotary axis of the crane.

10 Claims, 4 Drawing Figures ROTARY CRANE cated at a greater distance from the axis of rotation of the upper carriage, it is known to provide the intermediate piece, directly alongside the point of connection for the boom, with rollers which rest against the undercarriage of the crane.

This known supporting of the boom on the base by means of a roller, however, requires a relatively large base since, as a result of the use of the intermediate piece, the supporting roller rests on the base relatively far from the axis of rotation of the upper carriage. For this reason, in the known rotary crane it is necessary to provide platforms which can be connected with the base and on which the rollers can travel.

In other known rotary cranes, the boom is supported entirely on the upper carriage so that the upper carriage must sustain the entire load moment. Such a configuration requires that the upper carriage and the slewing track ring connected with the base must be made correspondingly heavy, which has a detrimental effect on the cost of the crane.

The object of the invention is to provide a rotary crane in which the upper carriage can be developed as small and light as possible, and in which the support for the upper carriage need not sustain the entire load moment of the boom.

This object is attained in a rotary crane of the aforementioned type in accordance with the present invention in the manner that for the supportingof the boom there is provided a supporting member or pin which is axially displaceably guided by the upper carriage, the guide axis forming an angle with the horizontal (i.e., being upwardly directed) and the roller being carried by the end thereof which faces the base. In this way the result is obtained that, without having to increase the size of the upper carriage substantially, the latter need not sustain the entire load moment of the boom.

In this connection, a guide boom can be supported directly on the end of a supporting guided pin extending upwardly and away from the roller. In a rotary crane in which one end of the boom is supported directly on the upper carriage and an extendable strut, e.g., lift-cylinder mechanism, acts on it at a distance from the boom support, the end of the lift-cylinder mechanism facing away from the boom can be supported on the supporting pin. In this way, the entire load to be taken up by the lift-cylinder mechanism is supported via the lift pin and the roller on the lower carriage or base.

The invention makes possible the design of an upper carriage of extremely small size, in which case it is also possible to provide a raceway or track (for the supporting roller) of the smallest possible diameter; as a result, the width of the base, for instance of a lower ciarriage, can also be reduced.

The invention will be explained in detail in the following description of greatly simplified embodiments of rotary cranes in accordance with the invention, shown schematically in the drawing in which: 1

FIG. 1 is a side view in elevation of a first embodiment;

FIGS. 2 and 3 are an enlarged fragmentary side and front views, respectively broken away and partially in section, of the front end of the upper carriage of the embodiment of FIG. 1 supported rotatably on a base;

FIG. 4 is a view corresponding to FIG. 2 to illustrate a second embodiment.

On a chassis 1 serving as base, an upper carriage 3 is supported by means of a slewing ring 2 for rotation around a vertical axis 4, a boom 5 being supported on said upper carriage for swinging around a horizontal axis 6.

At its front end, the upper carriage 3 has two exten sions 7 and 7a, respectively provided with square guide openings 8 and 8a, the longitudinal axes of which extend upwardly, being practically vertical and thus forming an angle with the horizontal; the guide axes are substantially in the vertical plane of the boom 5 and the axis 4 of crane rotation, being preferably inclined slightly away from axis 4, as shown. In these openings 8 and 8a, there are supported for axial displacement square guide members, pins or

bolts

9 and 9a, each of which is suitably bushed, as suggested at 21-22, and bears at its lower end a fork 11 (11a) in which a roller 12 (12a) is supported for rotation. The axis of rotation of each of-the two rollers 12 and 12a extends substantially horizontal and radial to the axis of rotation 4 of the upper carriage 3.

The upper ends of the

pins

9 and 9a, i.e., facing away from the rollers 12 and 12a, are equipped with ball joints 13 and 13a which serve for pivotally connecting bearing pins 14' and 14a of the cylindrical bodies 15 and 15a of liftcylinder mechanisms 16 and 16a with the

square pins

9 and 9a. The piston rods of the lift cylinders 16 and 16a are, as can be noted from FIG. 1, pivotally connected with the boom 5 at a distance offset from the axis 6 of said boom. 1

Due to the fact that the openings 8 and 8a as well as the

square pins

9 and 9a have substantially identical square cross-section, the axes of rotation of the rollers l2'and 12a will always be held in such a manner that they extend radial to the axis of rotation 4 of the upper carriage 3 and in this way can easily travel on a raceway 17 of the chassis l, upon rotation of the upper carriage 3. And since the

square pins

9 and 9a are axially displaceable in the openings 8 and 8a, there is automatic accommodation to any and all unevenness or irregularity in the raceway l7, and the upper carriage 3 will not be required to carry that part of the weight of the boom 5 which is sustained by the strut or lift-cylinder means 16 and 16a. Due to the fact that the

pins

9 and 9a cannot turn in the square openings 8 and 8a, the axes of rotation of the rollers are at all times held in a radial position with respect to the axis of rotation 4 of the upper carriage 3 so that a proper rolling of the rollers 12 and 12a on the raceway 17 is at all times assured. Instead of the square cross-sections of the

pins

9 and 9a and of the openings 8 and 80, any other known device to prevent rotation, as for example, by using keyed

cylindrical pins

9 and 9a, may be provided.

By supporting the boom 5 on the rollers 12 and 12a, the upper carriage 3 is very extensively relieved of load so that it and the slewing track 2 can be made lighter and of smaller diameter, thus creating the possibility of also making the chassis l narrower without thereby reducing the load carrying capacity of the boom.

Instead of two

pins

9 and 9a, one single pin can also be provided. lnstead of supporting a lift cylinder for the boom 5 on the upper end of the

pins

9 and 9a, as in the embodiment shown here, the lower end of the boom can also be supported there in the case of a guided boom or derrick configuration.

In the embodiment shown in FIG. 4, all the parts which correspond to the parts of the embodiment shown in FIGS. 1-3 are designated by reference numbers which have been increased by 100, so that reference may be thereby made to the preceding description.

The embodiment of FIG. 4 differs from the preceding embodiment merely by the fact that, in this case, bearing supports 118 are rigidly connected by means of two

pins

119 and 120 to the extensions 107 and 107a of the upper carriage 103 for the supporting of the pins 109 and 109a. These bearing supports, in the same way as the extensions 7 and 7a of the preceding embodiment, also have square openings 108 (108a) in which the square pins 109 (1090) in the bearing bushings 121-122 can move axially but cannot rotate.

What is claimed is:

1. A vehicular rotary crane, comprising an upper carriage rotatably supported on a chassis includingupwardly facing circular track means concentric with the axis of carriage rotation and fully contained within the chassis planform, a boom connected to and rotatable with said carriage, and boom-supporting means including at least one roller having rolling contact with said track means, said boom-supporting means including a floating member carrying said roller and movably guided by said carriage on an upwardly extending axis offset from the axis of rotation of said carriage, the base end of the boom being directly supported on said carriage, and said boom-supporting means including a lift cylinder connected to act between said member and a point on said boom offset from the boom connection to said carriage.

2. A rotary crane according to claim 1, in which said member is a pin slidably guided by said carriage.

3. A rotary crane according to claim 2, in which said pin is non-rotatably guided.

4. A rotary crane according to claim 2, in which said pin is one of two, said pins being independently guided by said carriage on upwardly extending axes which are spaced from each other about the rotary axis of the crane.

5. A vehicular rotary crane, comprising a chassis frame, an upper carriage supported for rotary displacement about a vertical axis on said frame, upper and lower boom members having spaced pivotal connection to said carriage and being pivotally connected to each other at a location offset from said carriage, an upwardly facing circular track on said frame about said axis and beneath a radially offset part of said carriage, one of said boom-member connections to said carriage being in generally vertical overlapping register with the radial offset of said track; said one boom-member connection comprising thrust-sustaining pin means positioned by said carriage and having a degree of freedom of vertically guided movement with respect to said carriage and connected to the lower end of the applicable boom member, said pin means including roller means supported for thrust-sustaining rolling contact with said track, whereby said pin means relieves the carriage from a substantial component of the vertical load sustained via said applicable boom member, regardless of unevenness in said track about said axis.

6. A rotary crane according to claim 5, in which the pin member is of non-circular section and has a keyed relation to its vertically guided connection to said carriage, the axis of said roller being oriented generally radially of the axis of carriage-rotation.

7. The crane of claim 12, in which said applicable boom member is one of two lower boom members connected at their upper ends to said upper boom member, and in which said thrust-sustaining means is one of two pin members slidably guided on upwardly extending axes which are angularly spaced about the rotary axis of the crane, the respective lower ends of said lower boom members being independently connected to said pin members.

8. The crane of claim 12, in which the pin means is guided substantially in the vertical plane of boom orientation and is offset from the vertical.

9. A rotary crane according to claim 5, in which said applicable boom member is an extendable strut.

10. The crane of claim 9, in which said extendable strut includes a hydraulic lift cylinder having pinned connection to said member.

Claims

1. A vehicular rotary crane, comprising an upper carriage rotatably supported on a chassis including upwardly facing circular track means concentric with the axis of carriage rotation and fully contained within the chassis planform, a boom connected to and rotatable with said carriage, and boomsupporting means including at least one roller having rolling contact with said track means, said boom-supporting means including a floating member carrying said roller and movably guided by said carriage on an upwardly extending axis offset from the axis of rotation of said carriage, the base end of the boom being directly supported on said carriage, and said boomsupporting means including a lift cylinder connected to act between said member and a point on said boom offset from the boom connection to said carriage.