EP2216285A1 - Control for an adjustable boom extension of a mobile crane - Google Patents

Abstract

The controller has a jib extension placed on a telescoping main jib (2). A luffing angle of the jib extension is adjustable by a luffing winch or a piston-cylinder unit. The actuation of the winch moving a luffer (1) or the piston-cylinder unit is carried out via a control circuit such that an angle (30) of the luffer with respect to the telescoping main jib and/or an horizontal remains constant or changes to a predefined extent during extension and/or retraction of the telescoping jib, or when changing the angle of the main jib with respect to the horizontal.

Description

The invention relates to a control for an adjustable boom extension of a mobile crane, with a telescopic main boom and a patch on this boom extension, the luffing angle is adjustable by means of a tipping winch or a piston-cylinder unit.

It is known to provide cranes with boom extensions to increase the reach or the reachable lift height.
These can either be firmly connected to the main boom or rotatable about an axis, so be arranged rocker.

In a rocking boom extension, which is also abbreviated as rocker, the desired position of the rocker, so the rocking angle relative to the horizontal, for example, adjusted and held by a winch.

When the main boom is extended or retracted, or the angle of the main boom is changed, the winch for the rocker must also be actuated, either to change the angle of the rocker relative to the horizontal or to keep it constant.

Usually, the operation of the tipping winch in these cases is done by the crane operator, the tipping winch then - takes up or emits rope - for example, according to the Teleskopiergeschwindigkeit.

For example, if the crane operator has to simultaneously control, for example, the hoist, main boom angle, and / or telescoping operation during these crane movements, additional operation of the tipping winch will require significant additional attention, since migration of the hook in a horizontal or vertical direction is avoided must, ie the hoist must be operated in any case, to avoid a collision of the bottle with the rocker or the environment.

The invention is therefore based on the object to achieve a simplification of the control operations for the crane operator.

This object is achieved according to the invention with a control for an adjustable boom extension of a mobile crane, with a telescopic main boom and a patch on this boom extension whose rocking angle is adjustable by means of a tipping winch or a piston-cylinder unit, characterized in that the control of the rocker moving rocker or piston-cylinder unit via a control circuit is such that when you extend or retract the telescopic boom or when changing the angle of the main boom relative to the horizontal, the angle of the rocker to the telescopic main boom or to the horizontal remains constant or in changes to a predetermined level.

During telescoping, the angle of the rocker relative to the horizontal is initially increased and then kept constant.

Preferably, when telescoping, from a predetermined extension of the main boom, the angle of the rocker relative to the horizontal is kept constant.

The adaptation of the Wippwinkels, and thus the use of the control according to the invention, but is also required if the angle of the main boom relative to the ground changes. The adjustment of the angle of the main boom is usually done by hydraulic cylinders or else via winches, which are called retractors.

This has nothing to do with telescoping as long as the angle of the main boom does not necessarily change during telescoping.

It is essential that in all the situations mentioned above, the control or activation of the rocker is done automatically, so that the crane operator does not have to perform this movement process manually together with the other controls.

For safety reasons, of course, a manual intervention in the control curtains is possible at any time.

The invention will be explained below with reference to the drawings.

• Fig. 1 schematisch einen Mobilkran mit teleskopierbarem Hauptausleger und verstellbarer Auslegerverlängerung in einem ersten Längenzustand und einem ersten Auslegerwinkel,
• Fig. 2 einen zweiten Längenzustand des Hauptauslegers,
• Fig. 3 einen veränderten Auslegerwinkel und
• Fig. 4 eine mit einem Zylinder verstellbare Auslegerverlängerung.

Showing:

• Fig. 1 schematically a mobile crane with telescopic main boom and adjustable boom extension in a first longitudinal state and a first boom angle,
• Fig. 2 a second length condition of the main boom,
• Fig. 3 a modified boom angle and
• Fig. 4 a cylinder-adjustable boom extension.

On the chassis 3 of a mobile crane, a main boom 2 is arranged, whose individual shots 2 (see FIG. 2 ) are retractable and retractable.

At the head 5 of the innermost shot an adjustable boom extension (rocker) 1 at the pivot point 20 is articulated.

The rocker is guyed over a guy string 14, the rocking support 15, the guy string 11, the flying sheave 10 and the seesaw 12, which is posted on the rope or tipping winch 16.
This type of bracing the rocker is common, so that it need not be discussed here further.

The FIG. 2 shows a extended boom 2, in which the angle 31 of the main boom has remained the same as the angle 30 of the boom extension or rocker first
When extending the main boom, the winch 16 must yield rope, so that the angle of the adjustable boom extension or rocker 1 maintains the predetermined angle 30.

In the transition from the in the FIG. 2 position shown to the in FIG. 3 shown position, both the angle 31 of the main boom as well as the angle 30 of the boom extension or rocker 1 has been changed, but only with the rocker relative to the main boom and not to the horizontal, so that on the one hand rope must be delivered by reducing the angle 31 of the main boom, but on the other hand also by the erection of the boom extension - the angle 30 relative to the main boom has become larger - rope is added.

As explained above, telescoping on the one hand had to be controlled by the crane operator and on the other hand the cable winch or winch would be actuated in order to first increase the rocking angle and then control the tracking or release of the rope so that the rocking angle remains constant.

The same applied to a change in the angle of the main boom.

In the FIG. 4 Finally, a variant is shown in which the angle change or constant maintenance of the adjustable arm or the rocker 1 by a rocking cylinder 40 takes place. As with the previously described winch, in this variant, the angle of the adjustable arm is changed by this rocker cylinder 40 coordinated.

With the solution according to the invention, which automatically adapts the rocking angle, the crane operator is relieved of this simultaneous rocking control requiring a very high level of attention.

This solution ensures that the luffing angle 30, ie the angle between rocker 1 and main boom 2, even during a change of the main boom (telescoping) or a change in the angle 31 of the main boom 2 can be kept constant or defined. If this is not done, for example, when extending the main boom 2 due to the geometry of 1, 2, 15, 11 and 12, the luffing boom extension 1 would be pulled "backwards". Although there are usually on such a crane limit switch or the like, which prevent a rollover of 1 to the rear by switching off the movement, however, a shutdown of the movement is not to be regarded as desired or comfortable.
When shortening the boom 2 without tracking the rope 12 would tilt by just this geometry, the boom extension 1 down.
The same applies to changing the rocking angle 30.

LIST OF REFERENCE NUMBERS

1

adjustable boom extension

2

boom

3

chassis

4

Rocker boom

5

rigid boom extension

10

flying pulley

11

Guy rope 1

12

Wippseil

14

Guy rope 2

15

luffing

16

luffing winch

20

Fulcrum of the rocker

30

luffing

31

boom angle

40

Rocker cylinder adjustable boom extension

Claims (3)

Control for an adjustable boom extension of a mobile crane, with a telescopic main boom and a jib extension mounted thereon, whose rocking angle is adjustable by means of a tipping winch or a piston-cylinder unit,
characterized,
that the control of the rocker moving winch or piston-cylinder unit via a control circuit is such that when you extend or retract the telescopic boom or when changing the angle of the main boom relative to the horizontal, the angle of the rocker to the main telescopic boom or Horizontal remains constant or changes in a predetermined amount. Control according to claim 1,
characterized,
that when telescoping the angle of the rocker relative to the horizontal initially increased and then kept constant. Control according to claim 1,
characterized,
that when telescoping from a predetermined extension of the main boom, the angle of the rocker is kept constant relative to the horizontal.

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