RU2268234C1 - Load-lifting crane movable counterweight - Google Patents

Abstract

FIELD: materials handling facilities; cranes.

SUBSTANCE: proposed counterweight contains two parts, each being secured on one arm of corresponding lever. Levers are arranged at sides of turntable of load-lifting crane and are hinge-secured on cross beam connecting two movable trolleys moving along inclined running beams arranged along sides of load-lifting crane turntable. Trolleys are provided with cantilevers arranged along inclined running beams and connected with arms of levers by tackle blocks having one common wire rope connected with running off line of freight tackle block of crane through equalizing block consisting of two rollers so that two lines of common rope should pass to tubular beam. Said tubular beam connects both cantilevers. Levers are provided with two stops for limiting turning from maximum to minimum out reach of counterweight. Trolleys are installed on inclined running beams for moving along beams under action of tackle block having common wire rope connected with equalizing block of rope whose ends are secured on head of crane boom in case of boom crane, o to triangular post of hook in case of crane of tower-and-boom make.

EFFECT: increased mass of hoisted load, reduced total mass of crane.

5 dwg

Description

The present invention relates to the field of crane construction, and in particular to a movable counterweight of a hoisting crane that synchronously changes the reach depending on the change in the reach of the crane boom and the size of the transported cargo.

Currently, most self-propelled cranes are equipped with (at least domestic) stationary counterweights.

Such cranes have limited capacity and reach.

This is expressed by the equation

(1) To _G.U. = To _s.u. = 1.15 is an ideal case where

To the _city - coefficient of cargo stability of the crane,

To _s.u. - coefficient of own stability of the crane.

From equation (1) it can be seen: increasing the outreach and mass of the counterweight in order to increase the carrying capacity and outreach of the crane boom, the coefficient of self-stability at the minimum outreach of the crane boom decreases and reaches the limit K _s.u. = 1.15.

A further increase in the counterweight threatens to tip the crane with a minimum boom without lifting the load.

To avoid tipping over, artificially increase the mass of that part of the crane, the center of gravity of which is between the tipping ribs, increase the base of the crane. Such cranes are not mobile and are transported in parts on trailers, railway platforms. It is very laborious, time consuming and expensive.

Gantry cranes with movable counterweights are known.

The closest analogue is a movable counterweight, disclosed in SU 626024 A1, 08.16.1978, "Balancing device of the boom." The known prototype contains common features with the claimed invention: a movable counterweight containing two parts, each of which is mounted on one shoulder of the corresponding lever.

The disadvantage of the prototype is that the total moment from both parts of the counterweight balances the moment only from the mass of the boom, but not the load, otherwise an increase in the reach of the boom without load will be impossible (the moment from the counterweight will be more than the moment from the boom).

The objective of the proposed movable counterweight is to increase the transported load, while ensuring the condition of equation (1) by balancing not only the moment from the mass of the boom, but also the moment from the load, reducing the total mass of the crane, the ability to install the rotary part of the crane on automobile or pneumatic chassis as more modern and mobile compared to tracked and rail, the versatility of the counterweight, allowing you to use the proposed movable counterweight on any crane:

with a rope mechanism for maneuvering the boom of a crane, beak;

with hydraulic boom maneuver mechanism;

with rack and pinion boom maneuver.

This problem is solved in that in the movable counterweight of the crane, containing two halves, each mounted on one shoulder of the corresponding lever, according to the invention, the levers are located on the sides of the rotary platform of the crane and pivotally mounted on a transverse beam connecting two movable trolleys moving along inclined driving beams located on the sides of the rotary platform of the crane, having consoles located along the said beams, and connected to the shoulders of the levers hoists with a common rope connected to the run-off thread of the crane hoist through the equalization block of two rollers so that two branches of the common rope fit to the tubular beam connecting both arms from opposite sides, and the levers have two stops to limit rotation from maximum to the minimum departure of the counterweight, the trolleys are mounted on inclined driving beams with the possibility of moving along them using a chain hoist having a common rope connected to the equalization unit of the cable traction, the ends to otoroy fixed to the head of the boom of the crane, if the crane is in the boom version, or to the triangular rack shunting beak, if the crane in the tower-boom version.

The invention is illustrated by drawings, where

figure 1 shows a General view of a self-propelled crane with the claimed counterweight in the boom;

figure 2 - General view of the crane in a tower-boom;

figure 3 is a diagram of the stocking of tackle consoles carts;

figure 4 is a diagram of the storage of trolley chain hoists for a crane in a jib;

figure 5 - scheme for the storage of trolley chain hoists for a crane in a tower-jib version.

The proposed movable counterweight (Figs. 1, 2) consists of two halves 2, each of which is fixed to one shoulder of the corresponding lever 1. In Figs. 1, 2, 16 denotes a two-legged crane stand, and 17 denotes a chain-link for changing the boom extension.

The levers 1 are located on the sides of the rotary platform 18 of the crane, pivotally mounted on the transverse tubular beam 4, which connects two movable carts 3, which are additional counterweights that move along the inclined driving beams 5 located on the sides of the rotary platform 18 of the crane.

Trolleys 3 have consoles 6 located along the driving beams 5, two double-flange wheels on top of the driving beam and two double-flange wheels on the bottom of the driving beam, so that when moving the trolleys they do not jump off the driving beams.

The consoles 6 are connected to the shoulders of the levers 1 by chain hoists 7 having a common rope 8. The common rope 8 is connected to the run-off thread 9 of the cargo chain block 10 of the crane by an equalizing unit 11 consisting of two rollers, so that two branches of the common rope fit to the tubular beam 12 connecting both consoles on opposite sides.

The levers 1 have two stops, limiting the rotation of the lever from the minimum departure of the counterweight to the maximum.

Carts 3 have the ability to move along the ride beam with the help of trolley chain hoists 13 (see figures 4 and 5). Both trolley pulleys 13 have a common rope and are connected by a leveling block 14, consisting of two rollers, with a cable tie 15, the ends of which are fixed to the head of the crane's boom, if the crane is in a boom design, or to a triangular strut of a shunting beak, if the crane is in a tower-boom crane performance.

When the crane lifts the load, the levers 1 begin to rotate around the hinges, moving the counterweights 2 in the direction of increasing the departure, under the influence of the chain hoists 7, the efforts of which depend on the effort in the run-off thread of the cargo chain block 10 of the crane, which in turn depends on the mass of the load and the number thread in the cargo sheave 10 crane.

With an increase in the outreach of the boom under the influence of trolley chain hoists 13, the trolleys 3 synchronously move upward along the inclined driving beams 5, and synchronously downward with a decrease in the outreach under the influence of the ramp component from the mass of the trolleys and counterweights, the angle of rotation of the levers 1 does not change when the outreach of the crane boom changes.

Example:

Let the tilt angle of the ride beam α = 6 °,

S = 2.5 t - force in the jib pulley, or the pulley of the beak maneuver,

n = 2 - the number of threads in the trolley sheave 13.

The condition of the balance of the trolley when moving uphill.

(one trolley 3 and one counterweight 2)

where R _tel is the mass of the trolley,

P _ol - the mass of the counterweight,

f _Tr - coefficient of friction in the bearings of the wheels of the trolley,

for two carts, the mass of carts and balances will be 40.3 tons.

The equilibrium condition of the trolley when moving downhill:

S _ck - (P + _{P-body etc.)} · (Sinα- (P + _{P-body etc.)} f _ck = (P + _{P-body etc.)} · (Sinα-f _rp) = (P + _{P-body etc.)} · (0,104- 0.02) = 20.16 · 0.084 = 1.74 t <S = 2.5 t,

at S≤1.74 the trolley moves downhill,

S _sk - rolling force.

From the calculations it can be seen that the total mass of trolleys and balances can be quite large (in this example, 40 tons). At first glance, it seems that the balances on the levers are redundant and can be permanently fixed on the bogies, but then it may turn out that the coefficient of self-stability is less than the allowable Xu <1.15 and that there is a need to reduce the mass of the counterweight, which automatically entails a decrease in the mass of the crane cargo.

Claims (1)

A movable counterweight of a hoisting crane, comprising two halves, each mounted on one shoulder of the corresponding lever, characterized in that the levers are located on the sides of the swing platform of the hoisting crane and are pivotally mounted on a transverse beam connecting two movable trolleys moving along inclined driving beams located on the sides a slewing crane platform having consoles located along said beams and connected to the arms of the levers with pulleys having a common rope, soy trolley-mounted with a run-down thread of the crane hoist through the leveling block of two rollers so that two branches of the common rope fit to the tubular beam connecting both arms from opposite sides, and the levers have two stops to limit rotation from the maximum to the minimum outreach of the counterweight, movable trolleys mounted on inclined driving beams with the possibility of moving along them using a chain hoist having a common rope connected to the equalization unit of the cable traction, the ends of which are fixed to the head at the boom of the crane, if the crane is in the boom version, or to the triangular rack of the shunting beak, if the crane is in the tower-boom version.

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