EP3738918A1

EP3738918A1 - Boom with moveable counter weight

Info

Publication number: EP3738918A1
Application number: EP19174455.6A
Authority: EP
Inventors: Michael STRANDBERG; Kenneth Lundberg
Original assignee: S&L Access Systems AB
Current assignee: S&L Access Systems AB
Priority date: 2019-05-14
Filing date: 2019-05-14
Publication date: 2020-11-18

Abstract

The present disclosure relates to a boom (1) for a flat-top crane (2). The boom (1) comprises an elongated frame arrangement (3) and a counterweight (4) and being_characterized in that the counterweight (4) is movably attached to the elongated frame arrangement (3) such that it can move along at least 50 % of the length of the elongated frame arrangement (3). The present disclosure also provides a flat-top crane (2) comprising a boom (1) according to boom a tower attachment arrangement (7) for attaching the boom (1) to a tower, the tower attachment arrangement (7) being arranged such that the boom (1) protrudes on both sides of the attachment arrangement. The flat-top crane (3) being characterized in that the counterweight (4) of the boom (1) is movably attached to the boom (1) such that it can pass the tower attachment arrangement (7) and be moved between the protrusions of the boom (1).

Description

Technical field

The present invention relates to a boom for a flat-top crane and a flat-top crane.

Background

Cranes are used in many different fields, mainly when building or repairing structures. Cranes are commonly employed in the transport industry for the loading and unloading of freight, in the construction industry for the movement of materials, and in the manufacturing industry for the assembling of heavy equipment.
There are three major considerations in the design of cranes. First, the crane must be able to lift the weight of the load; second, the crane must not topple; third, the crane must not rupture.
Due to the high usability of cranes, there is always a need for improving cranes.

Summary

It is an aim of the present invention to provide an improved boom and flat-top crane.
This aim is achieved by a boom as defined in claim 1 and a flat-top crane as defined in claim 12.
The disclosure provides a boom for a flat-top crane, the boom comprising an elongated frame arrangement and a counterweight. The counterweight is movably attached to the elongated frame arrangement such that it can move along at least 50 % of the length of the elongated frame arrangement. The counterweight is thus moveable past where the boom is attached to a tower. The counterweight is thus more flexible in where it can be arranged.
According to some aspects, the boom comprises two hoisting arrangements for hoisting loads, the hoisting arrangements being arranged at a respective end of the boom and both hoisting arrangements being independently connected to the counterweight. The counterweight can thus be used as counterweights for hoisting arrangements on both sides of the tower holding the boom.
According to some aspects, the hoisting arrangements are hoist rope, wire ropes or chains.
According to some aspects, the counterweight is movably attached with a sled comprising at least two wheels and the elongated frame arrangement comprises a wheel-track for guiding the wheels of the sled along the length of the elongated frame arrangement.
According to some aspects, the counterweight is movably attached with at least one pinion arranged on the sled and a corresponding rack on the elongated frame arrangement.
According to some aspects, the counterweight is movably attached with wheels attached to the counterweight and the elongated frame arrangement comprises a wheel-track for guiding the wheels along the length of the elongated frame arrangement.
According to some aspects, the counterweight is movably attached with at least one pinion arranged on the counterweight and a corresponding rack on the elongated frame arrangement.
According to some aspects, the elongated frame arrangement comprises two separable parts for simplifying transportation.
According to some aspects, the elongated frame arrangement is a lattice arrangement.
According to some aspects, the counterweight is arranged on any one of: a top side of the elongated frame arrangement, inside the elongated frame arrangement and on the sides of the elongated frame arrangement. If the counter weight is attached to the underside of the boom, it cannot pass the tower when the boom is attached to a tower. If the tower is attached to the boom on a side of the boom, the counterweight may also be attached to the underside of the boom.
According to some aspects, the counterweight is movably attached to the elongated frame arrangement such that it can move along at least 70 %, and preferably 80 % of the length of the elongated frame arrangement. How long the counterweight should be moveably attached may vary depending on how heavy loads the crane is to lift.
The disclosure provides a flat-top crane comprising a boom according to any of the above features, a tower attachment arrangement for attaching the boom to a tower. The tower attachment arrangement being arranged such that the boom protrudes on both sides of the attachment arrangement. The counterweight of the boom is movably attached to the boom such that it can pass the tower attachment arrangement and be moved between the protrusions of the boom. Advantages have been discussed above.

Brief description of the drawings

The invention will now be explained more closely by the description of different embodiments of the invention and with reference to the appended figures.

Fig. 1 shows an example boom.
Fig. 2 shows an example boom with a counterweight.
Fig. 3 shows an example boom from above with several examples of positions of the counterweight.
Fig. 4 shows a perspective view of a boom with a crane house.
Fig. 5 shows an example showing one part of a boom with a sled for the counterweight.
Fig. 6 shows an example showing the other part of the boom.
Fig. 7 shows the same as figure 5 from a perspective view.
Fig. 8 shows a zoomed in view of a sled with corresponding when tracks on the boom.
Fig. 9 shows a view from behind of a boom with a crane house.
Fig. 10 shows an example flat-top crane with a boom, a counterweight and two hoisting arrangements independently attached to the counterweight.

Detailed description

The present invention is not limited to the embodiments disclosed but may be varied and modified within the scope of the following claims.
Aspects of the present disclosure will be described more fully hereinafter with reference to the accompanying drawings. The devices and methods disclosed herein can, however, be realized in many different forms and should not be construed as being limited to the aspects set forth herein. Like numbers in the drawings refer to like elements throughout.
The terminology used herein is for the purpose of describing particular aspects of the disclosure only, and is not intended to limit the invention. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.
The general idea of the disclosure is to provide a boom and a flat-top crane where the counterweight is moveable across the boom attachment of the tower to the crane. The boom and flat-top crane may also be provided with double lifting points connected to the same movable counterweight. The same counterweight can then be moved from one side of the boom to the other to act as counterweight to hoisting arrangements 5 on both sides of the boom.
According to some aspects, each side of the boom may have a separate wire rope winch for hoisting loads and separate trolleys with pulley wheels to move the load along the crane arm. The two rope winches then work independently of each other and the two trolleys have separate drives to move each trolley independently along the respectively boom side.
When arranging a flat-top crane according to above, and the boom is arranged on the tower of center, the crane has one side for heavy lifts with short reach, since the boom side is shorter and one side for lighter lifts and longer reach, since the boom side is longer.
Figure 1 shows an example boom 1. Figure 2 shows an example boom 1 with a counterweight 4.
The disclosure provides a boom 1 for a flat-top crane 2, the boom 1 comprising an elongated frame arrangement 3 and a counterweight 4. The counterweight 4 is movably attached to the elongated frame arrangement 3 such that it can move along at least 50 % of the length of the elongated frame arrangement 3. The counterweight 4 is thus moveable past where the boom 1 is attached to a tower. The counterweight 4 is thus more flexible in where it can be arranged. According to some aspect the counterweight 4 is movably attached to the elongated frame arrangement 3 such that it can move along substantially the full length of the elongated frame arrangement 3. According to some aspects, the counterweight 4 is movably attached to the elongated frame arrangement 3 such that it can move along at least 70 %, and preferably 80 % of the length of the elongated frame arrangement 3. How long the counterweight 4 should be moveably attached may vary depending on how heavy loads the crane is to lift.
Flat-top cranes 2 for different uses may have different requirements for how long the counterweight 4 should be able to move to the ends of the boom 1. A heavier counterweight 4 may be used instead of being able to move the counterweight 4 all the way to the ends of the boom 1.
The counterweight 4 is movably attached to the elongated frame arrangement 3 such that, when the boom 1 is attached to a tower, the counterweight 4 can move past the tower attachment arrangement 7, where the boom 1 is attached to the tower. The counterweight 4 can thus be moved to an operative position on both sides of the tower. The movable counter weight can thus pass the crane house and be placed on the opposite side of the crane house to create equilibrium between the lifted load and the counterweight
According to some aspects, the movable counterweight 4 can move along the boom length and be positioned at any point along the boom 1.
According to some aspects, the boom 1 comprises two hoisting arrangements 5 for hoisting loads, the hoisting arrangements 5 being arranged at a respective end of the boom 1 and both hoisting arrangements 5 being independently connected to the counterweight 4. The counterweight 4 can thus be used as counterweight 4s for hoisting arrangements 5 on both sides of the tower holding the boom 1. In other words, the hoisting arrangements 5 are both independently attached to the counterweight 4 and can use the counterweight 4 to obtain equilibrium when hoisting loads. It should be noted that since the hoisting arrangements 5 are arranged on opposite sides of the boom 1 and thus on opposite sides of a tower holding the boom 1, the hoisting arrangements 5 cannot be used with the same counter weight at the same time.
The end of the boom 1 is defined as an end part of the boom 1 and is not the end side of the boom 1. As with a conventional flat-top crane 2, the hoisting arrangements 5 may be moveable along the length of the boom 1. Examples of such arrangements for such movements are shown in the figures. The arrangements and alternatives thereof are known to a skilled person and will not be explained in detail.
According to some aspects, the hoisting arrangements 5 are hoist rope, wire ropes or chains. The hoisting arrangements 5 may also comprise upper and lower sheaves. Hoisting arrangements 5 and variants thereof are also known to a skilled person.
Figure 3 shows an example boom 1 from above with several examples of positions of the counterweight 4. According to some aspects, the counterweight 4 is arranged on any one of: a top side 3i of the elongated frame arrangement 3, inside 3ii the elongated frame arrangement 3 and on the sides 3iii of the elongated frame arrangement 3. If the counter weight is attached to the underside 3iv of the boom 1, it cannot pass the tower when the boom 1 is attached to a tower. If the tower is attached to the boom 1 on a side of the boom 1, the counterweight 4 may also be attached to the underside 3iv of the boom 1.
Figure 4 shows a perspective view of a boom 1 with a crane house. In the figure, an example arrangement for raising and lowering the hoisting arrangements 5 is shown. In this example, the arrangement comprises two winches 5a, each for winching a respective hoisting arrangement.
The movable counter weight may run on a guiding system which can be wheels on a track, sliding bearings or a trolley. The guiding system is for moving the counterweight 4 and preferably prevent the counter weight from falling out of the guiding system. The drive of movable counter weight can be rack and pinion, wire and winch, wheels on a track, ball screw or rubber belt and wheels.
According to some aspects, the elongated frame arrangement 3 comprises two separable parts for simplifying transportation. The two boom parts may be connected in a mechanical joint between the two boom parts. Figure 5 shows an example showing one part of a boom 1 with a sled 6 for the counterweight 4. Figure 6 shows an example showing the other part of the boom 1.
Figure 7 shows the same as figure 5 from a perspective view.
Figure 8 shows a zoomed in view of a sled 6 with corresponding when tracks 3a on the boom 1. According to some aspects, the counterweight 4 is movably attached with a sled 6 comprising at least two wheels 6a and the elongated frame arrangement 3 comprises a wheel-track 3a for guiding the wheels of the sled 6 along the length of the elongated frame arrangement 3. The example sled 6 of figure 5 and 8 shows eight wheels. It is up to a system designer to choose the number of wheels suitable for the type of sled 6 and counterweight 4 they choose.
As can be seen in the figures, the boom 1 has an example wheel-track 3a which has a ridge over the wheels. The ridge is to secure the wheels to the track in the upwards direction such that the sled 6 and thus also the counterweight 4 is not able to leave the track.
According to some aspects, the counterweight 4 is movably attached with at least one pinion 6b arranged on the sled 6 and a corresponding rack 3b on the elongated frame arrangement 3. The sled 6 may also comprise at least two wheels.
According to some aspects, the counterweight 4 is movably attached with wheels 4a attached to the counterweight 4 and the elongated frame arrangement 3 comprises a wheel-track 3a for guiding the wheels along the length of the elongated frame arrangement 3.
According to some aspects, the counterweight 4 is movably attached with at least one pinion 4b arranged on the counterweight 4 and a corresponding rack 3b on the elongated frame arrangement 3. The sled 6 may also comprise at least two wheels.
Figure 9 shows a view from behind of a boom 1 with a crane house. In figure 9 it can be seen that a counterweight 4 can be arranged inside 3ii the boom 1. The example boom 1 illustrated in the figures is a lattice boom 1. According to some aspects, the elongated frame arrangement 3 is a lattice arrangement. The inside 3ii of the boom 1 is thus hollow and may house the counterweight 4. It should be noted that the illustrated winches are then not arranged inside 3ii of the boom 1 because they cannot be in the way of moving the moveable counterweight 4 across the boom 1. The winches, or any other suitable arrangement for hoisting the hoisting arrangements 5, may be arranged on top of the boom 1 or on a side of the boom 1 or on the underside 3iv of the boom 1.
Figure 10 shows an example flat-top crane 2 with a boom 1, a counterweight 4 and two hoisting arrangements 5 independently attached to the counterweight 4.
The disclosure provides a flat-top crane 2 comprising a boom 1 according to any of the above features, a tower attachment arrangement 7 for attaching the boom 1 to a tower. The tower attachment arrangement 7 being arranged such that the boom 1 protrudes on both sides of the attachment arrangement. The counterweight 4 of the boom 1 is movably attached to the boom 1 such that it can pass the tower attachment arrangement 7 and be moved between the protrusions of the boom 1. Advantages and alternative features of the flat-top crane 2 are the same as discussed above in connection to the boom 1.
The tower attachment arrangement 7 is for example a crane house on a slewing ring, two plates with a slewing ring between or the crane arm mounted directly on the top of the tower. It can be bolted or welded. The tower attachment arrangement 7 is any arrangement for fastening the boom to a tower.
According to some aspects, the flat-top crane 2 comprises a tower. The tower being connected to the boom 1 with the tower attachment arrangement 7. As can be seen in the figures, a crane housing for housing an operator of the crane, may also be arranged between the tower attachment arrangement 7 and the boom 1.

Reference list:

1.: Boom
2.: Flat-top crane
3.: Elongated frame arrangement
a. Wheel-track
b. Rack
i. Topside
ii. Inside
iii. Side
iv. Underside
4.: Counterweight
a. Wheel
b. Pinion
5.: Hoisting arrangement
a. winch
6. Sled
a. Wheel
b. Pinion
7. Tower attachment arrangement

Claims

A boom (1) for a flat-top crane (2), the boom (1) comprising:
- an elongated frame arrangement (3),

- a counterweight (4),
characterized in that the counterweight (4) is movably attached to the elongated frame arrangement (3) such that it can move along at least 50 % of the length of the elongated frame arrangement (3).
The boom (1) according to claim 1, comprising:
- two hoisting arrangements (5) for hoisting loads, the hoisting arrangements (5) being arranged at a respective end of the boom (1) and both hoisting arrangements (5) being independently connected to the counterweight (4).
The boom (1) according to claim 2, wherein the hoisting arrangements (5) are hoist rope, wire ropes or chains.
The boom (1) according to any preceding claim, wherein the counterweight (4) is movably attached with a sled (6) comprising at least two wheels (6a) and the elongated frame arrangement (3) comprises a wheel-track (3a) for guiding the wheels (6a) of the sled (6) along the length of the elongated frame arrangement (3).
The boom (1) according to any one of claims 1 to 4, wherein the counterweight (4) is movably attached with at least one pinion (6b) arranged on the sled (6) and a corresponding rack (3b) on the elongated frame arrangement (3).
The boom (1) according to any one of claims 1 to 4, wherein the counterweight (4) is movably attached with wheels (4a) attached to the counterweight (4) and the elongated frame arrangement (3) comprises a wheel-track (3a) for guiding the wheels along the length of the elongated frame arrangement (3).
The boom (1) according to any one of claims 1 to 4, wherein the counterweight (4) is movably attached with at least one pinion (4b) arranged on the counterweight (4) and a corresponding rack (3b) on the elongated frame arrangement (3).
The boom (1) according to any preceding claim, wherein the elongated frame arrangement (3) comprises two separable parts for simplifying transportation.
The boom (1) according to any preceding claim, wherein the elongated frame arrangement (3) is a lattice arrangement.
The boom (1) according to any preceding claim, wherein the counterweight (4) is arranged on any one of: a top side (3i) of the elongated frame arrangement (3), inside (3ii) the elongated frame arrangement (3) and on the sides (3iii) of the elongated frame arrangement (3).
The boom (1) according to any preceding claim, wherein the counterweight (4) is movably attached to the elongated frame arrangement (3) such that it can move along at least 70 %, and preferably 80 % of the length of the elongated frame arrangement (3).
A flat-top crane (2) comprising:
- a boom (1) according to any one of claims 1 to 11,

- a tower attachment arrangement (7) for attaching the boom (1) to a tower, the tower attachment arrangement (7) being arranged such that the boom (1) protrudes on both sides of the attachment arrangement,
characterized in that the counterweight (4) of the boom (1) is movably attached to the boom (1) such that it can pass the tower attachment arrangement (7) and be moved between the protrusions of the boom (1).