SU468868A1 - Boom Lift - Google Patents

Description

(54) ARROW LIFTING MECHANISM

one

The invention relates to boom equipment of load-lifting cranes.

Mechanisms for lifting a boom of a self-propelled crane are known, which contain a hydraulic cylinder that is articulated with an arrow and a supporting frame.

In order to obtain a constant angular velocity of the boom and reduce the pressure in the hydraulic cylinder, the hinge attaching it to the boom is placed in the groove of the latter and connected with two double-arm levers, which interact with the trunnions with which hydraulic cylinder

FIG. 1 presents the proposed mechanism, a general view; in fig. 2 and 3 show sections A-A and B-B in FIG. one.

The mechanism consists of a hydraulic cylinder 1, hinged on the support frame 2 and on the boom 3. The boom is equipped with a guide 4 with a groove 5 in which is located a pin 6 connecting the eye of the hydraulic cylinder 7 with the boom. The eyelet 7 has pins 8, which also enter the holes 9, made in the form of grooves at the ends of the double-arm levers 10. The levers 10 can be rotated relative to the fixed axis AND attached to the boom. To the opposite ends of these levers using fingers 12 pivotally attached

connecting rods 13, which are also connected by means of a finger 6 to an eye 7 of a hydraulic cylinder 1.

As can be seen (see Fig. 1), the shoulder action of the hydraulic cylinder relative to the center of rotation of the boom a ,.

When the boom moves, the angle a changes, the eyebolt 7 rotates relative to the finger 6, as a result of which the levers 10 are deflected, and with the help of connecting rods 13, the finger 6 with the eyelet 7 of the hydraulic cylinder moves in the direction of decreasing or increasing the distance R.

Moreover, the ratio of the distances and shoulders in the described mechanism is chosen such that the product Rsina h remains constant. Therefore, during the ascent process, the magnitude of the angular velocity does not change.

W: g 4, where Ush

stock speed

lindra. As a result of the fact that the shoulder remains constant, and does not decrease, as in the known constructions, the pressure value in the hydraulic cylinder also does not increase.

Subject invention

A self-propelled crane boom lifting mechanism comprising a hydraulic cylinder pivotally connected to the boom and a support frame, characterized in that, in order to obtain a constant angular velocity of the boom movement and decrease the pressure in the hydraulic cylinder, the hinge of lifting it to the boom is positioned in the slot of the latter and through connecting rods

It is connected with two double-arm levers turning around an axis fixed on the boom and interacting with the pivots mounted on the hydraulic cylinder.

12

. ;

Fig 5

FIG 2