EP2942318A1

EP2942318A1 - A crane track structure and a crane

Info

Publication number: EP2942318A1
Application number: EP15166745.8A
Authority: EP
Inventors: Petteri Lempiäinen; Mikko Erikkilä
Original assignee: Erikkila Oy
Current assignee: Erikkila Oy
Priority date: 2014-05-08
Filing date: 2015-05-07
Publication date: 2015-11-11
Also published as: FI20145426A

Abstract

The present invention relates to a crane track structure comprising a girder (101), wherein a portion of the girder (101) forms a runway providing at least one surface for at least one tyre of a trolley (107). The trolley is arranged to travel at least partly within the girder (101), and the said portion of the girder (101) further comprising at least one cavity (301) running at least partly along the length of the girder (101). The crane track structure further comprises at least one supporting means (305) arranged in the at least one cavity (301). The invention also relates to a crane comprising such a crane track structure.

Description

TECHNICAL FIELD

The invention concerns in general the technical field of crane solutions. Especially the invention concerns safety solution for crane tracks.

BACKGROUND OF THE INVENTION

Traditionally crane tracks are manufactured of track elements coupled together in some known manner. The track elements, also known as track profiles, are traditionally manufactured of iron, which has provided hard enough structure in order to meet the challenges in lifting heavy objects. However, the problem with the iron made track elements is that they are heavy to manufacture, but also to build up. Moreover, as the crane bridge is many times moved manually in the crane track from a first location to another the operation requires lot of power and energy.
The above mentioned challenges, among other reasons, established a need for light crane track structures especially in application areas wherein there is not necessary need for heavy crane solutions. In the light crane solutions the crane track is typically manufactured from steel or aluminum.
Fig. 1 illustrates an example of a crane solution in which the crane structure, i.e. the girder 101, is to be fastened in a ceiling with fasteners 103. A hoist 105 is coupled in the girder 101 with a trolley 107. The trolley 107 is arranged to travel along a runway arranged inside the girder 101 by means of shaping the inner part of the girder 101 accordingly. The crane solution in Fig. 1 is an example and there are multiple types of crane solutions available for need. The most common system has two parallel runways 101, trolleys 107 inside them and girder 101 fixed to those trolleys. The trolley 107 is arranged to travel along this girder (so called bridge crane).
Fig. 2 discloses a cross-sectional illustration on a crane track solution according to a prior art solution. The figure discloses the girder 101, the fastener 103 and the trolley 107. The trolley 107 comprises a body part 201 into which tyres 203 are fastened with a shaft. The sizes of the tyres 203, as well as material of the tyres, are advantageously adjusted to the size of the runway so that the rolling resistance is minimized. The hoist 105 is configured to be fastened in the trolley 107 with the shaft 205. Fig. 2 discloses how the runway for moving the trolley 107 along the girder 101 is achieved by shaping the girder 101. The control for moving the trolley 107 along the girder 101 and the control for using the hoist 105 may be arranged manually or by means of a controller, which provides control signals for motors within the trolley and the hoist. The delivery of control signals to the respective motors can be arranged either in wired or wireless manner by using known communication technologies.
One problem with the known solutions, especially when the crane track is manufactured from aluminum, is that the weight-carrying capacity, or at least the durability of such tracks, may be limited. In operation the course of the trolley along the girder 101 repeats itself i.e. many times the lifting and downlifting of a load happens in the same locations. Thus, the stress towards the crane track is emphasized in some locations of the track. Another fact is that the stress is shock-type in nature, especially when lifting a load, but also a continuous vibration exists towards the structure during the lifting and downlifting. The stress causes weakening of the track in the course of time and track may break down. In the worst case the trolley together with hoist and load may fall down, which causes damages in the crane solution and causes costs in a form of repairing costs but also in the form of downtime of the system. Moreover, the fall down of the mentioned parts may cause personal injuries to personnel operating the system.
Thus, there is continuous need for improving the safety in crane solutions.

SUMMARY OF THE INVENTION

An objective of the invention is to present a crane track structure and a crane for improving safety. Another objective of the invention is that the crane track structure and the crane improve safety by increasing an endurance of the crane track structure with the present invention.
The objects of the invention are reached by a crane track structure and a crane as defined by the respective independent claims.
According to a first aspect, a crane track structure comprising a girder is provided, wherein a portion of the girder forms a runway providing at least one surface for at least one tyre of a trolley configured to travel at least partly within the girder, the said portion of the girder further comprising at least one cavity running at least partly along the length of the girder wherein the crane track structure further comprising at least one supporting means arranged in the at least one cavity.
The supporting means may be configured to be fastened within the cavity in at least one of the following manner: chemically, mechanically. The mechanical fastening may be arranged by modifying a surface of at least one of the following: an inner wall of the cavity of the girder, supporting means. The mechanical fastening may also be arranged with at least one of the following: wedge-shaped structure of the supporting means, wedge or sleeve in at least one end of the supporting means.
The structure may further comprise at least one end plate mountable with the girder, wherein the at least one end plate comprises at least one through hole for conveying the supporting means through the end plate in order to fastening the supporting means with the end plate. The fastening of supporting means may be arranged with a fastening element against the end plate. The fastening of supporting means may also be arranged by bending at least part of the supporting means extending through the at least one through hole of the end plate against the end plate.
The supporting means within the structure may be at least one of the following: a flat bar, a tube, a cable, a wire or a wire rope.
According to a second aspect, a crane is provided wherein the crane comprises a crane track structure as described above.
The exemplary embodiments of the invention presented in this patent application are not to be interpreted to pose limitations to the applicability of the appended claims. The verb "to comprise" is used in this patent application as an open limitation that does not exclude the existence of also un-recited features. The features recited in depending claims are mutually freely combinable unless otherwise explicitly stated.
The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

Fig. 1: illustrates a crane solution according to a prior art,
fig. 2: illustrates a cross-sectional illustration on a crane track solution according to a prior art,
fig. 3: illustrates a structure according to an example of the present invention,
fig. 4: illustrates another example of a structure according to an example of the present invention, and
figs. 5 a-b: illustrate examples of an implementation of the invention according to the present invention.

DETAILED DESCRIPTION

The present invention relates to a utilization of a shape of a crane track profile for establishing a novel safety structure. Fig. 3 illustrates an example of a track profile in which the solution according to an example of the present invention is implemented. In the following detailed description it is used a term girder 101 in order to refer to track profile for emphasizing that the referred part in the crane solutions is the one in which the trolley 107 travels. The trolley 107 comprises the body part 201 and the tyres 203 coupled with the shaft to the body part 201. According to the invention the profile of the girder 101 is such that it comprises at least one cavity 301 traveling at least part of a length of the girder 101 and the location of the cavity 301 within the girder 101 is at least partly below the runway of the trolley 107. For the sake of clarity the runway of the trolley 107 refers to opening within the girder 101, which provides necessary surface or surfaces 303 on which the tyres 203 of the trolley 107 may roll when the trolley 107 is moved along the runway.
According to an example of the invention at least part of the at least one cavity 301 is configured to be equipped with a supporting means 305, which increases support to the structure and thus mitigating the risk that the girder 101 breaks down in the course of time. Additionally, as the supporting means 305 may advantageously be selected so that it is manufactured from a material having stronger durability than the girder 101 itself, the idea of equipping the girder 101 with the supporting means improves the safety even if the girder 101 breaks down. Namely, the supporting means 305 may increase the durability of the girder 101 to maintain its shape as well as to provide support for the trolley 107 if some break down of the girder 101 happens.
Some examples of the supporting means 305 are a flat bar, a tube, a cable, a wire or a wire rope. The flat bar or the tube may have a hollow or a solid structure. The supporting means 305 may be implemented by having one or more mentioned elements in any combination arranged in the at least one cavity 301 of the girder 101. The material of the supporting means may be, but is not limited to, iron, any alloy comprising iron, composite material, carbon fiber or nylon.
According to an example of the invention the size of the supporting means 305 is such that it may be push in the cavity by providing additional force to the supporting means 305. In other words, the supporting means 305 and the inner wall of the cavity 301 comprise such a mutual friction that the supporting means 305 locks removably within the cavity 301. Such an arrangement provides the necessary support also in case of breakdown of the girder 101 at some location. According to another example of the invention the supporting means 305 may be locked in the cavity 301 with some compound applicable for fastening two parts together. For example, the locking may be arranged by providing applicable glue between the inner wall of the cavity 301 and the supporting means 305, when the supporting means 305 are installed in the cavity 301 and thus fastening the supporting means 305 in the cavity 305. According to some further example of the invention the supporting means 305 may be equipped with some mechanical fastening means. The mechanical fastening means may e.g. be a hook arranged in at least one end of the supporting means 305, which may be hooked over the girder 101 at the respective end. It is also possible to arrange a specific anchor structure for the hook on the girder 101. Any similar mechanical fastening means to the hook may be used, such as an applicable wedge or sleeve incorporated at the end or ends of the supporting means 305. Furthermore, it is possible to modify the surface of the supporting means 305 so that it provides a mechanical locking when pushed in the cavity 301. For example, the surface may be modified by roughening it with a file tool or similar in order to increase the friction between the elements. Also, a lamella structure may be arranged on the surface of the supporting means 305 for gaining the frictional effect and thus locking the elements together as tightly as needed. It is also possible to modify the inner surface of the cavity 301 in order to increase the friction between the elements. In addition to the mentioned ways of implementing the necessary locking the supporting means 305 may be shaped in such a manner that it locks within the cavity 301. An example of the applicable cross-sectional shape of the supporting means may be a triangle with optimal dimensions for the cavity i.e. the apexes of the triangle touch the inner surface of the cavity along the length of the supporting means 301. Furthermore, the supporting means 305 may be wedge-shaped so that it is possible to convey in the cavity from one end of the girder 101 and by locking the other end with some locking means, the supporting means 305 is adjusted in place. Also in some implementations the cavity may be shaped in a manner that it provides locking arrangement into at least one direction with the supporting means 305. The cavity may e.g. be wedge-shaped into which an applicable supporting means 305 are inserted.
In typical implementations of crane tracks end plates are arranged to the girder 101. The purpose of the end plates is to limit the movement of the trolley 107, but also to protect the runway against dirt. Further, the end plates also limit the movement of cable trolleys as well as increase a strength of the structure in general and provides also fastening possibility of the track e.g. on the ceiling. Fig. 4 illustrates a crane track solution with a girder 101 equipped with the supporting means 305 according to the present invention in which end plates 401 are arranged to at least limit the runway of the trolley 107. The end plates 401 may be fastened with the girder 101 with known means, such as bolts, screws or similar.
In some crane track solutions so called joint element, such as a track joint, is used in coupling two track profiles together. The joint elements may be used in the similar manner as the end plates in providing tools for fastening the supporting means in the structure. Thus, in this context the term end plate shall be considered to cover any joint element used in crane tracks.
Fig. 5a illustrates a more detailed example of the present invention as a side view, when an end plate 401 is utilized in fastening the supporting means 305 within the structure. In the present example the supporting means 305 is such that it is flexible to adjust in the structure. The supporting means 305 may be a wire rope in the present example. An applicable through hole is arranged in the end plate 401 in order to convey the supporting means through the end plate 401. When the end plate 401 is fastened with the girder 101 it is possible to lock the supporting means 305 in the structure with an applicable fastening element 501. The fastening element 501 is advantageously such that it comprises a locking mechanism for the supporting means 305. For example, the fastening element 501 may comprise necessary number of through holes or grooves into which the supporting means 305 are to be adjusted and the locking may be arranged with screws 503, for example, as illustrated in Fig. 5b. The type of the fastening element 501 may differ from the one illustrated in Fig. 5a and Fig. 5b. In some example of the invention the fastening element 501 may be one or more bolts for which counter-holes are arranged in the end plate 401. Thus, the supporting means 305 may be fastened to the end plate 401 by tightening the one or more bolts when the supporting means 501 is arranged between the bolts and the end plate 401. The utilization of end plates 401 for fastening the supporting means 305 in the structure has also the advantage in providing a further stabilizing effect into the structure as a whole. This is because the supporting means 305 combines the end plates and thus stabilizes the whole structure.
According to some further example of the invention the supporting means 305, when it is manufactured from rigid material, may be conveyed through the end plates 401 via an applicable through holes and fastened by bending the supporting means 305 along the surface of the end plate 401. The bending may be implemented with any known manner by providing the necessary power for the supporting means 305.
When describing the present invention multiple inventive solutions are provided in order to fasten supporting means 305 to a crane track structure. Even if the inventive solutions are mainly described separately in the description above, it is possible to combine the separate solutions in any manner within the inventive idea defined in the independent patent claims. As a non-limiting example it is possible to utilize glue in fastening the supporting means 305 with the girder 101, but in addition to that it is possible to use the end plates for additionally fastening the supporting means 305 within the structure.
In some implementations of the present invention the supporting means 305 may be arranged only in some parts of the girder 101. Advantageously, they can be arranged to those locations into which the stress is directed to due to operational reasons.
Above it is disclosed a structure for improving safety in crane solutions. As said, the described structure advantageously prevents, or at least slows down, the drop down of the trolley if the runway of the trolley at least partly breaks down.
Some advantageous embodiments according to the invention were described above. The invention is not limited to the embodiments described. The inventive idea can be applied in numerous ways within the scope defined by the claims attached hereto.

Claims

A crane track structure comprising a girder (101), wherein a portion of the girder (101) forms a runway providing at least one surface for at least one tyre of a trolley (107) configured to travel at least partly within the girder (101), the said portion of the girder (101) further comprising at least one cavity (301), the cavity (301) running at least partly along the length of the girder (101), characterized in that the crane track structure further comprising at least one supporting means (305) arranged in the at least one cavity (301).
The crane track structure according to claim 1, wherein the supporting means (305) is configured to be fastened within the cavity (301) in at least one of the following manner: chemically, mechanically.
The crane track structure according to claim 2, wherein the mechanical fastening is arranged by modifying a surface of at least one of the following: an inner wall of the cavity (301) of the girder (101), supporting means (305).
The crane track structure according to claim 2, wherein the mechanical fastening is arranged with at least one of the following: wedge-shaped structure of the supporting means (305), wedge or sleeve in at least one end of the supporting means (305).
The crane track structure according to claim 1, wherein the structure further comprising at least one end plate (401) mountable with the girder (101), wherein the at least one end plate (401) comprises at least one through hole for conveying the supporting means (305) through the end plate (401) in order to fastening the supporting means (305) with the end plate (401).
The crane track structure according to claim 5, wherein the fastening of supporting means (305) is arranged with a fastening element (501) against the end plate (401).
The crane track structure according to claim 5, wherein fastening of supporting means (305) is arranged by bending at least part of the supporting means (305) extending through the at least one through hole of the end plate (401) against the end plate (401).
The crane track structure according to any of the preceding claims, wherein the supporting means (305) is at least one of the following: a flat bar, a tube, a cable, a wire or a wire rope.
A crane, characterized in that the crane comprises a crane track structure of any of the preceding claims.