|
(11) | EP 2 942 319 A1 |
| (12) | EUROPEAN PATENT APPLICATION |
|
|
|
|
|||||||||||||||||||||||||||
| (54) | SAFETY SOLUTION FOR CRANE TRACKS AND A CRANE |
| (57) The invention relates to a trolley (107) for a crane solution, which trolley (107)
is configured to travel along a runway arranged within a first channel of a girder
(101) being part of crane track. The trolley (107) is equipped with a safety element
(310) adjusted within the girder (101), which safety element (310) comprises at least
one surface for supporting the trolley (107) against the girder (101) if the trolley
(107) diverges from the runway over a distance defined at least partly by the safety
element (310). The invention also relates to a crane equipped with the trolley (107).
|
TECHNICAL FIELD
[0001] The invention concerns in general the technical field of crane solutions. Especially the invention concerns safety solution for crane tracks.
BACKGROUND OF THE INVENTION
[0002] 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.
[0003] The above mentioned challenges, among other reasons, has 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.
[0004] 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).
[0005] Fig. 2 discloses a cross-sectional illustration on a crane track solution according to a prior art. 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 so that it provides one or more surfaces on which the tyres of the trolley 107 may roll on. 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 may be arranged either in wired or wireless manner by using known communication technologies.
[0006] 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.
SUMMARY OF THE INVENTION
[0008] An objective of the invention is to present a trolley for a crane solution and a crane equipped with the trolley, which trolley is equipped with a safety element for increasing safety.
[0009] The objects of the invention are reached by a trolley and a crane as defined by the respective independent claims.
[0010] According to a first aspect, a trolley for a crane solution is provided, which trolley is configured to travel along a runway arranged within a first channel of a girder being part of crane track, wherein the trolley is equipped with a safety element adjusted within the girder, which safety element comprises at least one surface for supporting the trolley against the girder if the trolley diverges from the runway over a distance defined at least partly by the safety element.
[0011] The safety element may be arranged to travel along a second channel within the girder, which second channel differs from the first channel comprising the runway for the trolley.
[0012] The safety element may be shaped so that it extends from the first channel to the second channel through an opening within the girder. A width of a part of the safety element residing in the second channel may be arranged to be larger than a width of the opening within the girder.
[0013] The safety element may be configured to be removably coupled to a body part of the trolley. The coupling may be arranged with at least one of the following: screw, bolt, by welding.
[0015] According to a second aspect, a crane is provided, which crane is equipped with a trolley as described above.
[0016] 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.
[0017] 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
[0018]
- Fig. 1
- illustrates a prior art crane solution,
- fig. 2
- illustrates a cross-sectional illustration on a crane track solution according to a prior art,
- figs. 3 a-c
- illustrate crane solution elements forming the present invention,
- fig. 4
- illustrates an example of the invention as a side-view, and
- figs. 5 a-c
- illustrates examples of shapes of the safety element according to the present invention.
DETAILED DESCRIPTION
[0019] The present invention relates to a utilization of a shape of a crane track profile for establishing a novel safety structure. The principle of the present invention is to provide a safety element coupled to a trolley, which safety element is configured to travel along a channel in a girder together with the trolley, which channel in case of breakdown of a trolley runway in the girder provides support for the safety element so that a risk of fall down of the trolley from the girder may be mitigated.
[0020] Figures 3a-3c illustrate as an example an implementation of the safety solution according to the present invention. Fig. 3a depicts a girder 101 applicable to be used with the current invention. The girder 101 comprises a first channel (marked with A in Fig. 3a) providing a runway for a trolley and at least one second channel (marked with B in Fig. 3a), which at least one other channel comprises at least one surface 301 for a safety element coupled to the trolley in case of breakdown of the runway of the trolley. The distance between the supporting surfaces 301 is marked with d in the Fig. 3a.
[0021] Fig. 3b depicts a crane trolley 107 according to an example of the present invention. The trolley 107 comprises a body part 201 into which tyres 203 are fastened through 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. A hoist (not illustrated in Fig. 3b) is configured to be fastened in the trolley 107 through the shaft 205. A safety element 310 is configured to be coupled to the trolley 107. According to an example the safety element is a separate element to the body part 201 and is configured to be removably mounted with the body part 201 with some known fastening method adjusted to carry at least the weight of the trolley 107 and a load. The fastening method may comprise, but is not limited to, screws, bolts, welding among other applicable fastening methods. According to another example the safely element is implemented within the body part 201. In other words, the safety element 310 and the body part 201 is a one-piece solution produced e.g. by molding from an applicable material, such as iron. The size of the safety element is adjusted to match within the channel B so that in normal operation a friction provided by the safety element 301 is minimized, e.g. the safety element do not touch the girder 101 unless the runway of the trolley breaks down.
[0022] Fig. 3c illustrates the trolley 107 equipped with the safety element 310 arranged to travel in a channel of the girder 101 in a normal operation. In the normal operation the safety element 301 is preferably adjusted in the channel so that it does not touch any surface within the channel. Fig. 3d, in turn, discloses the operation of the safety element 310, when the runway of the trolley 107 is broken down. In such a case, the trolley 107 diverges from the runway over a distance defined at least partly by the safety element. The safety element 310 comprises a surface for supporting the trolley against the girder and thus the safety element carries at least part of the weight allocated to the crane track through the trolley i.e. the weight of the trolley as well as any load carried by the crane.
[0023] Fig. 4 illustrates an example of the invention as a side view. Fig. 4 illustrates the girder 101 and the trolley 107. The trolley 107 is equipped with a safety element 310. In case of the girder 101 breaks down e.g. under the tyres 203 of the trolley 107, the safety element 310 is configured to stop, or at least slow down, the fall of the trolley 107. This is achieved by shaping the safety element 301 so that in case of fall down at least some portion of the safety element 310 is adjusted to hit a surface 301 of the girder 101 within a channel in which the safety element 310 travels.
[0024] Figs. 5a-5c disclose some additional examples of possible shapes of the safety element 310 in addition to the one illustrated in previous figures. The shape may comprise a top part, which is shaped so that it provides hook-type shoulders (Fig. 5a) against the surface of the girder 101 if the runway of the trolley breaks down. The shape of the safety element may also be a ball-like top part (Fig. 5b). In some implementations the safety element 310 may comprise only one shoulder configured to be set against the surface of the girder 101 if the runway of the trolley breaks down, as depicted in Fig. 5c. The widths of the top parts are marked with W in Figs. 5a-5c. Advantageously, the width of the safety element as regards the portion of the safety element travelling in the channel as described shall be larger than the width d (see Fig. 3a). At maximum the width may be the width of the channel in the girder 101 in which the safety element is configured to travel. Moreover, a portion of the safety element 310 shall comprise a width, which is less than the width d defining the opening through which the safety element 310 is configured to mounted to the trolley 107. Alternatively or in addition to optimal dimensioning the corresponding elements within the crane solution it is possible to achieve the effect by shaping e.g. the channel in such a way that the safety element locks in the channel in case of fall down of the trolley. It shall be noted that shape of the safety element 310 is not limited to those as illustrated herein.
[0025] In the description above and in the attached figures it is disclosed that the channel in which the safety element is at least partly configured to travel locates above the channel into which the runway for the trolley 107 is implemented. However, the invention is not limited to such solutions only. For example, in some implementations the safety element may be arranged to travel along a channel, which locates below another channel forming the runway of the trolley 107. Moreover, the girder 101 may be shaped so that there exists only one channel implementing the runway for the trolley 107. However, the channel may comprise an additional cantilever, which may be utilized for the safety element 301 for achieving the same safety effect as described.
[0026] The term channel shall be understood as a cavity within the girder, which provides necessary structure for enabling a travelling of the trolley in a first channel within the girder and for enabling one or more surfaces in a second channel within the girder for providing support of the safety element to lean against if the runway fails to carry a weight allocated to the crane track through the trolley. The first and second channels are connected to each other through an opening so that the safety element may extend from the first channel to the second channel through the opening. The term 'channel' shall in this context be understood to cover any structure, such as an additional cantilever, which provides means for achieving the same effect as described.
1. A trolley (107) for a crane, which trolley (107) is configured to travel along a runway
arranged within a first channel of a girder (101) being part of crane track, characterized in that the trolley (107) is equipped with a safety element (310) adjusted within the girder
(101), which safety element (310) comprises at least one surface for supporting the
trolley (107) against the girder (101) if the trolley (107) diverges from the runway
over a distance defined at least partly by the safety element (310).
2. The trolley (107) according to claim 1, wherein the safety element (310) is arranged
to travel along a second channel within the girder (101), which second channel differs
from the first channel comprising the runway for the trolley (107).
3. The trolley (107) according to claim 2, wherein the safety element (310) is shaped
so that it extends from the first channel to the second channel through an opening
within the girder (101).
4. The trolley (107) according to claim 3, wherein a width of a part of the safety element
(310) residing in the second channel is arranged to be larger than a width of the
opening within the girder (101).
5. The trolley (107) according to claim 1, wherein the safety element (310) is configured
to be removably coupled to a body part (201) of the trolley (107).
6. The trolley (107) according to claim 5, wherein the coupling is arranged with at least
one of the following: screw, bolt, by welding.
7. The trolley (107) according to claim 1, wherein the safety element (310) is arranged
by shaping a body part (201) of the trolley (107).
8. A crane, characterized in that it is equipped with a trolley (107) according to any of the preceding claims.