Patent Application
20080083688
An embodiment example of the invention is shown in the drawings. The crane is constructed as a gantry crane which can move on a runway formed by two rails 1 laid at a distance from one another. A gantry crane of this kind usually has four legs 2, 3, 4, 5. Constructions with three legs are also known. Further, two supports can also be provided. The legs 2-5 and supports carry the transverse girder or transverse girders 6, 7 along which a trolley 8 is movable or which are provided with another type of movable or fixed hoisting device. When the construction is carried out with two or more transverse girders 6, 7, connection girders 9 extend between the latter.
An end carriage 10 is arranged at the lower ends of the legs 2, 3; 4, 5 arranged on a respective side of the gantry and connects them. The end carriages 10 serve to connect the steel construction of the crane to the individual traveling gear groups 11 of the crane traveling gear. A traveling gear group I of this kind is arranged below each of the legs 2-5.
It would also be conceivable and possible in principle, for example, to provide each leg 2-5 with its own end carriage 10. For each rail 1, there are preferably at least two traveling gear groups 11 at a distance from one another in longitudinal direction of the rail 1. An arrangement below a respective leg 2-5 is preferred.
In the present embodiment example, a respective traveling gear group 11 has eight wheels 12 at a distance from one another in longitudinal direction of the rails 1. The axles 13 of the wheels 12 are oriented at right angles to the rails 1. A respective wheel 12 can have two wheel flanges 14, 15 connected by an axle 13 at a distance from one another in transverse direction of the rail 1, as is shown schematically in
Two wheels 12 which are situated one behind the other in longitudinal direction of the rails are rotatably mounted in each instance at a subframe 16. In the present embodiment example, there are four subframes 16 per traveling gear group which lie one behind the other in longitudinal direction of the rails.
Two subframes 16 located one behind the other in longitudinal direction of the rails are connected to a common rocker 17. Accordingly, in the present embodiment example there are two rockers 17 at a distance from one another in longitudinal direction of the rails 1. The subframes 16 are connected to the rockers 17 so as to be swivelable around horizontal axes 18 extending at right angles to the rails.
The two rockers 17 are connected to a common rocker 19, and they are swivelable relative to the rocker 19 around a horizontal axis 20 extending at right angles to the rail 1.
Driving motors 21 which drive the respective wheels 12 serve to move the crane along the rails 1. The quantity of these driving motors 21 can vary depending on the application.
The respective end carriage 10 is connected to the respective traveling gear group 11 in such a way that the traveling gear group 11 is swivelable relative to the end carriage 10 around a horizontal axis extending at right angles to the respective rail 1 and is rotatable around a vertical axis. A connection device having a central joint 22 is provided for this purpose. This central joint 22 has at least the following degrees of freedom: a degree of freedom for rotating the traveling gear group 11 relative to the end carriage 10 around a vertical axis 23 and a degree of freedom for swiveling the traveling gear group 11 relative to the end carriage 10 around a horizontal axis 24 extending transverse to, particularly at right angles to, the respective rail 1.
In the present embodiment example, these degrees of freedom are formed by the construction of the central joint 22 in the form of a spherical joint or ball joint. In this case, the central joint 22 comprises a bearing pin 25 which is connected to the rocker 19, a bearing bush 26 connected to the end carriage 10, an inner race 27 which is arranged on the bearing pin 25 and has a spherical or spherical-segment-shaped outer surface, and an outer race 28 which is arranged in the bearing bush 26 and has a spherical or spherical-segment-shaped inner surface that cooperates with the spherical outer surface of the inner race 27. The joint could also be arranged “in reverse”, that is, the bearing pin 25 could be connected to the end carriage 10 and the bearing bush 26 could be connected to the rocker 19.
The central joint 22 is constructed as a floating bearing in vertical direction, i.e., it has play in this direction in the assembled state. Accordingly, this central joint 22 does not transmit any vertical forces. On the other hand, forces acting in horizontal direction are transmitted, namely, in direction of the respective rail 1 and at right angles to the latter.
Further, a respective connection device between the respective end carriage 10 and the respective traveling gear group 11 comprises two connecting rods 29, 30 which are arranged at both sides of the central joint 22 viewed in direction at a right angle to the rail 1. Each of the two connecting rods 29, 30 is connected in an articulated manner with the end carriage 10 and with the rocker 19. These joints 31, 32 of the connecting rods 29, 30, which lie one above the other, are constructed in such a way that compressive forces and tensile forces can be transmitted between the respective end carriage 10 and the respective traveling gear group 11 by the connecting rods 29, 30. These joints 31, 32 have at least the following degrees of freedom: a degree of freedom for swiveling the respective connecting rod 29, 30 relative to the end carriage 10 and also relative to the rocker 19 around an axis 33 extending at right angles to the respective rail 1 and a degree of freedom for swiveling the respective connecting rod 29, 30 relative to the end carriage 10 and relative to the traveling gear group 11 around a horizontal axis 34 extending parallel to the respective rail 1,
In the present embodiment example, the joints 31, 32 are constructed as spherical joints or ball joints. A bearing pin 35 is connected to the end carriage 10 and the rocker 19, respectively. An inner race 36 with a spherical or spherical-segment-shaped outer surface is arranged on the bearing pin 35. An outer race 37 with a spherical or spherical-segment-shaped inner surface that cooperates with the spherical outer surface of the inner race 36 is arranged in a respective bore hole of the connecting rod 29, 30.
Therefore, all occurring vertical forces are transmitted by the connecting rods 29, 30. These vertical forces result from the weight of the crane construction on one hand and from tilting moments on the other hand producing tensile forces paired with compressive forces. Horizontal forces are not transmitted by the connecting rods 29, 30 but, as was already mentioned, are transmitted by the central joint 22.
In a neutral or zero position of a respective traveling gear group 11 with respect to a rotation around the vertical axis 23, as is shown in the drawings, the two joints 31, 32 of a respective connecting rod 29, 30 lie exactly vertically one above the other. The connecting rods 29, 30 are preferably straight and their longitudinal axes are oriented in vertical direction in the zero position. A certain inclined position of the connecting rods 29, 30 is brought about by a rotation around the vertical axis 23 proceeding from this zero position. Accordingly, the joints 31, 32 of a respective connecting rod 29, 30 no longer lie exactly vertically one above the other. However, the required angle of rotation around the vertical axis 23 and therefore the deviations from the vertical orientation of the joints 31, 32 are very small. In typical applications, the straight connecting lines between the joints 31, 32 lying one above the other are inclined by less than 5°, preferably less than 3°, relative to the vertical in all of the angular positions of the occurring angular area of the rotation around the vertical axis 23. In practice, this angle is normally less than 1°.
Further, when deviating from the zero position, a force component acting around the vertical axis 2 occurs due to the weight of the crane, and this force component increases as the deviation from the zero position increases and is transmitted to the rails 1 by the wheels 12.
Further, when deviating from the zero position, there is a reduction in vertical play in the central joint 22 depending on the angle of rotation around the vertical axis 23. The vertical play in the central joint is large enough that it persists up to the maximum angle of rotation around the vertical axis 23.
When the traveling gear group 11 swivels around the horizontal axis 24 of the central joint 22, the connecting rods 29, 30 swivel around the horizontal axes 33 of the joints 31, 32. The horizontal axes 33 of the joints 31, 32 lie parallel to the horizontal axis 24 of the central joint 22.
The respective traveling gear group 11 can be rotatable relative to the respective end carriage 10 around the vertical axis 23 by at least 1°, for example.
The respective traveling gear group 11 can be swivelable relative to the respective end carriage 10 around the horizontal axis 24 of the central joint 22 extending at right angles to the rail 1 by at least 5°, for example.
A respective connecting rod 29, 30 can be swivelable relative to the respective rocker 19 around the horizontal axis 34 of the joint 32 extending at right angles to the rail 1 by at least 3°, for example.
A respective connecting rod 29, 30 can be swivelable relative to the respective rocker 19 around the horizontal axis 34 of the joint 32 extending parallel to the rail 1 by at least 1°, for example.
A respective connecting rod 29, 30 can be swivelable relative to the respective end carriage 10 around the horizontal axis 33 of the joint 31 extending at right angles to the rail 1 by at least 3°, for example.
A respective connecting rod 29, 30 can be swivelable relative to the respective end carriage 10 around the horizontal axis 34 of the joint 31 extending parallel to the rail 1 by at least 1°, for example.
A traveling gear group according to the invention can also have more or less than eight wheels 12 which are spaced apart in the movement direction. At least two wheels which are rotatably mounted at a common subframe 16 so as to be spaced apart from one another in longitudinal direction of the respective rail are provided.
When the traveling gear group is constructed with only one subframe, the central joint 22 can be arranged directly between this subframe and the end carriage, and the lower joint 32 of the connecting rods 29, 30 can likewise be arranged directly at the subframe.
For example, in a traveling gear with four wheels 12 arranged one behind the other in the traveling direction, two wheels can be rotatably mounted at a respective subframe and the subframe can be connected to a rocker 17 in the manner described above. In this case, the central joint 22 could be arranged directly between the end carriage 10 and this rocker, and the lower joints 32 of the connecting rods 29, 30 could be arranged directly between the connecting rods 29, 30 and this rocker.
Another embodiment form of the invention is shown schematically in
In contrast to the embodiment example shown in
The end carriage 10 has downwardly projecting connection portions 38 for articulating the connecting rods 29, 30 at the end carriage 10. A connection portion 38 of this kind extends downward on both sides of a portion of the traveling gear group 11, in this case, the rocker 17. The connection portions 38 each carry a joint 31 for articulating the respective connecting rod 29, 30.
The connection portions 38 can be U-shaped, for example, as is shown, and have two vertical sides 38a, 38b which are spaced apart in longitudinal direction of the rail 1 and which proceed from an opposite portion 39 of the end carriage 10 and are connected to one another at their lower ends by a horizontal web 38c. The joint 31 is arranged at this web 38c. Other constructions of the connection portions 38 can also be provided. For example, they can also be constructed in a continuous plate shape.
The description of the embodiment example shown in
For example, the traveling gear groups of a bridge crane could be connected to an end carriage of the steel construction of the crane in the manner according to the invention.
As follows from the preceding description, the range of the invention is not limited to the embodiment examples shown herein, but rather should be defined with reference to the appended claims together with their full range of possible equivalents. While the preceding description and drawings show the invention, it is obvious to a person skilled in the art that various modifications can be carried out without departing from the spirit of and field of the invention.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2006 047 997.1 | Oct 2006 | DE | national |
