SU1677012A1 - Telescopic boom of load-hoisting mechanism - Google Patents

Abstract

The invention relates to lifting and transport equipment. The purpose of the invention is to increase the reliability of operation by providing self-centering of the sections and increasing the rigidity in the plane of lifting of the load. The boom contains fixed and inner extension sections in the form of box-shaped beams with side vertical walls interconnected by upper and lower shelves, the latter having a V-shaped cross section, as well as sliding supports. The upper section shelf is made similar to the lower one, i.e. V-shaped, with the formation of hexagonal section of the box girders of the sections. 3 il.

Description

This invention relates to a lifting machinery industry, in particular to telescopic booms.

The purpose of the invention is to increase reliability by providing self-centering of the sections and increasing rigidity in the plane of the suspension of the load.

Figure 1 shows the telescopic arm of the manipulator, general view; figure 2 - section aa in figure 1; on fig.Z - section bb in figure 1.

The telescopic boom contains a fixed section 1 and a movable section 2 entering into it. Each section is made in the form of a box-section beam with side vertical walls 3 and with upper 4 and lower 5 shelves, respectively. In cross section, shelves 4 and 5 have a V-shaped profile with an angle a.

The angle a of the V-shaped shelves is chosen in the range of 90-150 ° depending on the magnitude and direction of the force applied to the boom: the greater the vertical forces, the greater the angle a. In this particular case, the angle a is 120 °.

When the angle a decreases, the specific pressure on the supports increases sharply, and due to the fact that the horizontal component of the reaction of the supports exceeds the vertical, seizure of the sections between them occurs and, accordingly, intensive wear of the sliding supports.

As the angle og increases, as a rule, reliable self-centering of the sections between themselves is not ensured, since it is possible to move the movable section in the transverse plane due to the fact that the horizontal component of the support reaction is reduced to zero, and therefore uneven wear of the sliding supports occurs.

The box-shaped beams of the boom sections can be made in the form of two sidewalls from sheet metal of a curved profile, cross section

Yo

with

Xi

x | ABOUT

Yo

the idea of which is an equilateral trapezium, and welded together at the base.

The device also contains sliding supports 6 in the amount of eight pieces. The supports are installed in pairs between the V-shaped shelves of the sections. In this case, the four supports are fixed at the free end of the fixed section 1 (Fig. 3) and four - on the root part of the sliding section 2 (Fig-.2). Slide supports are made of durable plastic. With significant wear, the supports can be adjusted with backing plates. A hydraulic cylinder 7 is located inside the sections for extending sections 2.

When loading the boom in the plane of suspension of the load and when moving the movable section under load, carried out by the hydraulic cylinder 7, the forces arising in the supports 6 of the fixed section 1 are transmitted to the faces of the V-shaped shelves of the sliding section 2. Thanks to the hexagonal section of the box-shaped beams with V- the various upper and lower shelves ensure reliable self-centering (self-installation) of the inner section 2 relative to the fixed section 1, which contributes to the uniform distribution of the load on the respective sliding supports 6 and, consequently, a decrease in the specific pressure on the shelves and uniform wear of the supports. At the same time reliable self-centering of sections between themselves

happens both when the manipulator is hoisted on a lift, and when it is pressed (in the push mode, the boom works, for example, when loading a long whip handle on

timber truck, the code must click on the end of the whip).

The boom design has increased strength under the action of vertical, horizontal and torsional forces, since

the latter are perceived by the V-shaped shelves of box girders, whose faces are located at a certain angle to the direction of action of these efforts. This makes it possible to increase the reliability of work.

and durability of the boom.

Claims (1)

Claims of invention and pull-out sections of the box section, formed by each side vertical walls connected by an upper and V-shaped cross section of the lower shelves, and installed between the shelves of the sliding support sections, so as to increase the reliability of the operation by ensuring the sections self-centering and increasing stiffness in the plane of suspension of the load, top shelf Each section has a V-shaped, upward-facing section, with the tops of the upper and lower shelves of all sections placed in the vertical plane of symmetry of the boom. 1 Aa FIG. 2 6-6 Figz