SU1216133A1 - Jib crane - Google Patents

Description

The invention relates to hoisting-and-transport mechanisms, namely to construction cranes, intended for the production of assembly and disassembly works in cramped conditions.

The purpose of the invention is to increase the convenience of operation.

FIG. 1 schematically shows a jib crane, general view; in fig. 2 is a view A of FIG. 1 (compensating polispast); in fig. 3 is a scheme for stocking a cargo depot; in fig. 4 shows the shape of the curvilinear axis of the guide mounted on the frame.

The jib crane contains a turntable 1, on which the boom 2 is installed, a mechanism 3 for raising and lowering

the catfish and the polar axis coinciding respectively with the center of the joint (axis 8) of the rotation of the boom 2 and the horizontal axis passing through the center of the joint (axis 8);

L is the length of the arrow.

Ensuring unchanged the height of the lifting hook of the crane when changing its departure is as follows. With the help of the mechanism 3 for raising and lowering (hydraulic cylinders) of the boom 2, its angle of inclination to the horizon is changed. When this occurs, movement occurs in the guides 4 and 5 of the movable cage of blocks 9, seated on axis 10 and mounted with

booms (hydraulic cylinders) and two curvilinear 5 using rollers 11 and 12 in guides 4 guides in the form of channels, 4 and 5. Since axis 10 is a simultaneous profile. The boom 2 is equipped with directionally mounted in guides 4 and 5, 5, made with grooves 6 and someone its position is strictly fixed and with a blocking polyspast, which hangs from the angle of inclination of the boom 2 to the armature of blocks 7, installed on axis 8 by an umbrella. With the increase of this angle, the collar of the boom 2 gate, the movable block of block-blocks 9 on the axis 10 approaches the cladding 9 on the axis 10, mounted with the blocks of 7 mounted on the axis 8, with the power of rollers 11 in the grooves 6 -reduction is removed. As a result of this, 5 and rollers 12 in curvilinear, respectively, are etched or selected by guides 4. Compensating polyspast rope 13, stocked on blocks 7, is formed by freight rope 13, skirting the 25 and 9, and ensures that the blocks 7 are immutable and 9. Cargo rope 13 od-honeycomb suspension hook crane when changing

By its end, it is fixed on the drum of the winch 14 and, by skirting the blocks 15 and 16, forms a pulley of the hook suspension 17. The axis 18 of the curvilinear guides 4 mounted on the platform 1 has the shape defined by the equation

p / L (l-sin f, -) ,.

where p, and ф, - are the polar coordinates, the polar radius and the polar angle of the i-th point of the axis 18 of the departure curve, respectively, since p, (polar radius) value is variable and found from the relation (Fig. 4)

L p + Lsinffi

Thus, lengthening and shortening of the load rope 13 is not associated with the operation of the lifting winch 14, depends on the change in the angle of inclination of the boom 2 to the horizon, automatically and ensures that the lifting height of the hook of the crane track 4 remains unchanged when changing its departure.

the catfish and the polar axis coinciding respectively with the center of the joint (axis 8) of the rotation of the boom 2 and the horizontal axis passing through the center of the joint (axis 8);

L is the length of the arrow.

Ensuring unchanged the height of the lifting hook of the crane when changing its departure is as follows. With the help of the mechanism 3 for raising and lowering (hydraulic cylinders) of the boom 2, its angle of inclination to the horizon is changed. When this occurs, movement occurs in the guides 4 and 5 of the movable cage of blocks 9, seated on axis 10 and mounted with

Using rollers 11 and 12 in guides of heads 4 and 5. Since the axis 10 is simultaneously mounted in guides 4 and 5, its position is strictly fixed and depends on the angle of inclination of the boom 2 to the horizon. With an increase in this angle, the yoke of blocks 9 on the axis 10 approaches the yoke of blocks 7 mounted on the axis 8, and decreases with decreasing. As a result, the cargo rope 13, stocked on blocks 7 and 9, is etched or selected, respectively, and the height of the crane hook suspension is constant when changing

its departure, since p, (polar radius) value is variable and found from the relation (Fig. 4)

L p + Lsinffi

Thus, lengthening and shortening of the load rope 13 is not associated with the operation of the lifting winch 14, depends on the change in the angle of inclination of the boom 2 to the horizon, occurs automatically and ensures that the lifting height of the crane hook remains unchanged when its departure changes.

13

17

fig.Z

FIG. four

Claims (1)

ARROW CRANE containing a rotary platform on which the boom is pivotally mounted on an axis with the possibility of rotation in a vertical plane, compensating a chain hoist, including a stationary clip of blocks and a cargo rope with a chain hoist of a hook suspension, characterized in that, in order to increase the convenience of operation, it is equipped with curved guides rigidly mounted on the turntable on both sides of the boom symmetrically relative to its longitudinal axis, while the lower part of the boom is made with grooves, and The hoisting pulley is made with a multiplicity equal to the multiplicity of the pulley of the hook suspension and is equipped with an additional clip of blocks having a common axis, mounted with the possibility of movement by means of rollers in curved guides and the said grooves of the boom, and its branches are formed by a freight rope, and a fixed clip of blocks is mounted on the axis rotation of the boom, and the shape of the curvilinear guides is determined by the shapes ul e r = L (ί —sirup, ·), where p, and φ, · are the polar coordinates, respectively, the polar radius and polar angle of the i-th point o a guide rail with a pole and a polar axis, coinciding respectively with the center of the hinge of rotation of the boom and the axis passing through the center of the hinge; L is the length of the boom. FIG. 1