US 3111226 A
Abstract available in
Claims available in
Description (OCR text may contain errors)
E. KIRSTEN TRUCK CRANE Nov. 19, 1963 3 Sheets-Sheet 1 Filed Sept. 18, 1962 K My .5 r
E. KIRSTEN TRUCK CRANE Nov. I 19, 1963 3 Sheets-Sheet 2 Filed Sept. 18, 1962 Jn ventar: E P715 Z A1}: Ze-rz A zzys. W
Nov. 19,1963 E. KIRSTEN I v 1 TRUCK CRANE I Filed Sept. 18, 1962 s Sheets-Sheet s 3,111,226 TRUCK CRANE Erhard Kirsten, Kell, Kreis Trier, Germany Filed Sept. 18, 1962, Ser. No. 224,367 Claims priority, application Germany Sept. 19, 1961 6 Claims. (Cl. 212-59) The problem that arises in truck cranes is that the torsion capacity of the vehicle frame must not be impaired too greatly by the crane superstructure. For this reason, it has already been proposed not to mount the crane rigidly on the vehicle frame, but to arrange it yieldingly in relation to the twisting of the vehicle frame. This is done by mounting the base plate of the crane, on which the rotary superstructure of the crane with the jib is supported, by means of a pivot at that end face thereof which is located at the front so as to be pivotable and longitudinally displaceable on the vehicle frame, rubber bearings forming the rear supports for the base plate. When travelling with a load, :however, such surface pressures occur at the pivot that the pivotal bearing is put out of action.
The main object of the present invention is to provide for the crane superstructure weight conditions which maintain the capacity of the crane superstructure for pivotal movement and longitudinal displacement with respect to the vehicle frame under all load conditions.
According to the invention, the rotary superstructure is equipped with a platform projecting in the opposite direction to the jib and on which the winch, its driving motor and other crane assemblies and a counter-weight for the weight of the load are arranged. In this way, the weight loading heretofore produced at one end by the jib and the weight of the load is fully or at least partially compensated, whereby the pivot bearing of the base plate of the crane is relieved of load so that the bearing is kept operational. The ballast weight thereby produced with respect to the jib and the weight of the load has the :further result that the crane can be designed for higher loads and is able to support them without tipping of the vehicle having to be feared.
In a three-axle vehicle, the rotary superstructure equipped with a jib is preferably so mounted that the axis of the rotating ring support or turntable support of the crane superstructure coincides with the central axis between the rear axle assemblies.
The base plate of the rotary superstructure is supported at the rear by two laterally arranged rubber bearings, so that practically speaking there is created for the base plate held at the front by the pivot a three-point mounting which provides the most favourable conditions as regards the capacity of the base plate for pivotal movement and longitudinal displacement.
The object of the invention is illustrated by way of example in the drawing, in which:
FIGURE 1 is a diagrammatic side view of the truck crane as designed in accordance with the invention;
FIGURE 2 is a rear view of the truck crane, the superstructure of the crane being swung through 90;
FIGURE 3 is a longitudinal section through the pivot bearing of the base plate on a larger scale;
FIGURE 4 is a front view of the pivot bearing as seen in the direction of the arrow A in FIGURE 3;
FIGURE 5 is a longitudinal section through a rear rubber bearing of the base plate;
FIGURE 6 is a fragmentary section on the line A-B of FIGURE 5, and
FIGURE 7 shows a detail on a larger scale.
In the truck crane illustrated diagrammatically in the drawing, the vehicle frame on which the crane is mounted is designated by the reference 1. The crane itself consists as regards its main parts of the superstructure 3 capable United States Patent 0 0 3,111,226 Patented Nov. 19., 1963 of rotary movement by means of the rotating ring mounting or turntable mounting 2 and of the understructure thereof formed by the box-shaped base plate 4. To the superstructure 3 is articulated the jib 5 which is adapted to be extended by means of the telescopic tubes 6. The reference 7 designates the load hook. Vertical adjustment of the jib 5 is effected by means of the hydraulic draw device 8. The superstructure 3 of the crane has a platform 9 projecting in the opposite direction to the jib 5 and on which are arranged, inter alia, the winch 10 and the hydraulic motor 11. In addition, a ballast or counterweight 12 is also arranged on the projecting platform.
The entire rotary superstructure of the crane is supported by means of the rotating ring mounting or tumtable mounting 2 on the base plate 4, which consists of a box rendered rigid by reinforcement and inside which, for example, the petrol or oil tanks can be accommodated. The base plate 4 is supported at its front end face by a pivot 13 held in the bearing 14. The bearing 14 is fixed rigidly to the vehicle frame 1 by means of lateral flanges 15. Ribs 116 are provided for reinforcing the bearing flanges. The supporting pivot 13 is secured against longitudinal movement by means of a plate 17 engaging in a groove. Thus, by loosening the fixing screw 18, it is possible in simple manner to withdraw the supporting pivot 13 from the base plate 4 and exchange it if necessary. The mounting of the crane is correspondingly simple.
FIGURES 5 to 7 illustrate the rear rubber bearings for the base plate 4 which have an upper casing 19 fixed to the base plate 4 and a lower casing 20 fixed to the vehicle frame 1, between which casings the rubber block 21 is housed. The upper and lower casings have outer edges 19', 20' engaging one over the other and which leave freedom for play between them, the outer edges 19' forming limit stops for the longitudinal movement of the base plate 4 with respect to the frame 1. Securing of the bearings is effected by means of through bolts 22 passed through bores with a clearance which are provided in the box-shaped base plate 4 and the vehicle frame 1, washer elements 23 having a spherical bearing surface 23' assisting the flexibility of the connection. Angle plates 24 are fixed to the frame 1 for the engagement of the through bolts and the box-shaped base plate 4 is also reinforced by a support plate 25. Distance sleeves 26 are used for further reinforcement.
In FIGURE 2, the rotary superstructure of the crane has been swung out of the longitudinal direction of the vehicle through It can be seen particularly clearly here how the crane assemblies arranged on the projecting platform 9, namely the winch 10, the hydraulic motor 11, the hydraulic draw device 8 and the swing drive 27 of the superstructure with its hydraulic motor, become operative as a counter-weight for the load suspended from the load hook 7. The ballast weight 12 takes effect in the same way. To support the truck crane laterally, removable auxiliary supports 23 may also be fitted as a precaution.
1. A truck crane comprising a vehicle frame, a rotary superstructure with a jib supported by a box-shaped base plate which is mounted by means of a pivot at that end face thereof which is located at the [front so as to be pivotable and longitudinally displaceable on the vehicle frame, rubber bearings forming the rear supports for the base plate, the rotary superstructure comprising a platform projecting in the opposite direction to the jib and on which a winch, its driving motor and a counterweight for the weight of the load are arranged, and a rotating ring support for the crane superstructure near the rear end of the base plate and the vehicle frame.
2. A truck crane according to claim 1, characterised in that in a three-axle vehicle the axis of the rotating ring support for the crane supperstructure is located on a central axis between rear axle assemblies.
3. A truck crane according to claim 1, in which two laterally arranged rubber bearings are provided for the base plate of the rotary structure to support the plate at the rear.
4. A truck crane according to claim 1, in which two laterally arranged rubber bearings are provided for the base plate of the rotary structure to support the plate at the rear, and in which an upper casing is fixed to the base plate and a lower casing is fixed to the vehicle frame with the rubber bearings in between the two casings and leaving a limited clearance for movement between the casings in which the rubber #bearings are accommodated.
5. A truck crane comprising a vehicle frame, a rotary superstructure with a jib and in the form of a box-shaped base plate which is mounted by means of a pivot on the vehicle frame, rubber bearings forming the supports for the base plate, the rotary superstructure comprising a platform projecting in the opposite direction to the jib and a rotating ring support for the crane superstructure and the vehicle frame, an upper casing fixed to the base plate, and a lower casing fixed to the vehicle frame, said rubber bearings being provided in the casings.
6. A truck crane according to claim 5, in which the casings each have edges engaging one over the other with a clearance :for movement and which term limit stops, to prevent too extensive longitudinal movements of the base plate with respect to the vehicle frame.
No references cited.