EP2611723B1

EP2611723B1 - Mounting and control solution for a lift bogie's travelling wheel

Info

Publication number: EP2611723B1
Application number: EP11773738.7A
Authority: EP
Inventors: Mikko Hoffrén
Original assignee: Cargotec Finland Oy
Current assignee: Cargotec Finland Oy
Priority date: 2010-08-30
Filing date: 2011-08-18
Publication date: 2015-03-04
Anticipated expiration: 2031-08-18
Also published as: FI20105896L; FI124036B; FI20105896A0; WO2012028770A1; FI20105896A; EP2611723A1

Description

FIELD OF THE INVENTION

The invention concerns a mounting and control solution for a lift bogie's travelling wheel in accordance with the preamble to claim 1.
In the handling of containers, such lift bogies are generally used, which travel on rails. After the field welding of the lift bogie, it is often necessary to correct the alignment of the lift bogie's travelling wheels. Deformations and inaccuracies of the lift bogie's steel structure are the usual cause for the necessity to align the travelling wheels.
Inaccurate alignment of the lift bogie's travelling wheels is one of the most significant factors causing wear of travelling wheels and rails. In order to minimize wear, the alignment must be as accurate as possible. To ensure a sufficient lifetime for the lift bogie's travelling wheels and rails, various standards set limit values for permissible alignment errors. The permissible values are achieved either with strict manufacturing tolerances for the lift bogie's body or with functioning control mechanisms for the travelling wheels.

PRIOR ART

Mounting and control solutions of different kinds have been presented in the art for the travelling wheels of lift bogies. For example, it is generally known to use one or more eccentrics in the mounting and control solution for a lift bogie's travelling wheel.
EP patent 626 336 presents a mounting and control solution for the travelling wheel, which allows control of the vertical alignment and the travelling alignment of a lift bogie's travelling wheel. The solution is based on the use of two eccentrics, one within the other. The outer eccentric is formed by a support plate, in which an eccentric support surface is formed. A bushing is mounted on the eccentric support surface of the support plate. Another eccentric is formed in the inner surface of the bushing. The support surfaces of the support plates are located with the same eccentricity in relation to the central line of the shaft as the eccentricity of the midpoint of the bearing housing. A first bushing located on the first side of the travelling wheel is fitted into the first support surface in such a way that the eccentricity between them is mainly in the vertical direction, and the second bushing located on the second opposite side of the travelling wheel is fitted into the second support surface in such a way that the eccentricity between them is mainly in the horizontal direction. The travelling direction of the travelling wheel is aligned by turning the first bushing, and the vertical inclination of the travelling wheel is aligned by turning the second bushing.
In the solution presented in EP patent 626 336 , the bearing structure must be removed entirely from the lift bogie's body structure to allow changing of the gauge. In solutions according to prior art, the gauge is usually changed with the aid of spacer plates suitable for the purpose.

SUMMARY OF THE INVENTION

The mounting and control solution in accordance with the invention for a lift bogie's travelling wheel is simple, quick and easy to use.
The characteristic features of the mounting and control solution in accordance with the invention for a lift bogie's travelling wheel are presented in the characterizing part of claim 1.
In the invention, the mounting and control solution for a travelling wheel is based on the use of two nesting bearing housings. The outer bearing housing is used for mounting the bearing structure to the lift bogie's body. The inner bearing housing is formed like a cylinder, whose inner periphery is eccentric in relation to the outer periphery. The inner bearing housing is locked to the outer bearing housing with a friction lock. This makes it possible, on the one hand, to turn the inner bearing housing step-lessly in the peripheral direction in relation to the outer bearing housing. Turning of the inner bearing housing peripherally in relation to the outer bearing housing will change the alignment of the eccentric, whereby the travelling wheel's alignment will also change. On the other hand, the inner bearing housing can also be moved step-lessly in the axial direction in relation to the outer bearing housing, whereby the travelling wheel's position in the axial direction can be controlled.
Step-less control of the travelling wheel's alignment and gauge allows the use of larger eccentricity, whereby a larger maximum control is achieved without making the control more inaccurate.
Step-less control of the travelling wheel's alignment and gauge also allows larger tolerances in the manufacture of the lift bogie's body.
The invention is described in the following by referring to the figures in the appended drawings.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a view of a lift bogie.
Figure 2 shows an axonometric view of the mounting of a travelling wheel to a beam in the lift bogie's body structure.
Figure 3 is a vertical cross-sectional view of the travelling wheel's mounting shown in Figure 1.
Figure 4 is an exploded view of a bearing structure in accordance with the invention.
Figure 5 is a side view of the bearing structure shown in Figure 4.
Figure 6 shows the inner bearing housing of the bearing structure shown in Figure 5.
Figure 7 is an exploded view of another bearing structure in accordance with the invention.

DESCRIPTION OF PREFERRED EMBODIMENTS

Figure 1 shows a view of a lift bogie. The lift bogie 100 moves on rails 11a, 110 b located in the top part of a crane. Under the lift bogie 100 there is a lifting mechanism 120, which can be used for lifting and lowering containers. The containers can also be moved in a horizontal direction by making the lift bogie 100 travel along the rails 110a, 110b of the crane.
Figure 2 shows an axonometric view of the mounting of a lift bogie's travelling wheel to a beam in the lift bogie's body structure, and Figure 3 is a vertical cross-sectional view of the travelling wheel's mounting shown in Figure 2.
The solution comprises a shaft 10, whose inner end is connected to a drive motor 30, which is used for rotating the shaft 10. The shaft's 10 outer end is supported on the inside and outside of travelling wheel 20 through a bearing structure 40 to a beam P in the lift bogie's body structure. The bearing structures 40 located on opposite sides of travelling wheel 20 are identical. The bearing structure 40 comprises an outer bearing housing 41 and an inner bearing housing 42. The outer bearing housing 41 is mounted with bolts 50 to the beam P in the lift bogie's body structure, and the shaft 10 is supported by a bearing element to the inner bearing housing 42. The axial direction is indicated by reference marking X-X, and the vertical direction is indicated by reference marking Y-Y. The inner bearing housing 42 extends in the axial direction outside the outer bearing housing 41. In that part of the inner bearing housing 42, which extends outside the outer bearing housing 41, shapes can be made, for example, for a spanner wrench, whereby it is easier to turn the inner bearing housing 42 in the peripheral direction. For moving the inner bearing element 42 axially, suitable protruding parts can be formed in the inner bearing housing 42 and in the outer bearing housing 41, from which protruding parts the inner bearing housing 42 can be moved in the axial direction using a suitable tool. In the outer bearing housing 41 and in the inner bearing housing 42, control markings can be made, and based on these it is possible to perform control of the inner bearing housing 42 in the peripheral direction and in the axial direction.
Figure 4 is an exploded view of a bearing structure according to the invention. The bearing structure 40 comprises an outer bearing housing 41 and a cylindrical inner bearing housing 42. In the outer bearing housing 41 there is a first axial bore 41a, which receives the inner bearing housing 42. The bearing structure 40 also comprises a bearing element 43, whose inner periphery fits on the shaft's 10 outer periphery and whose outer periphery fits on the inner bearing housing's 42 inner periphery 42a. A roller assembly is located in between the bearing element's 43 inner periphery and outer periphery. The bearing element's 43 end is closed to the inner bearing housing 42 with a cover plate 44. In the outer bearing housing 41 there is also a second bore 41b, which is in a transverse direction in relation to the first bore 41 a and which extends through the outer bearing housing 41 into the first bore 41a. The second bore 41b comprises an interior thread at least in its outer part. The second bore 41b receives a wedge 45 and a first screw 46. In the inner edge of wedge 45 there is an oblique friction surface 45a, which fits against the inner bearing housing's 42 outer periphery 42b. The inner end of the first screw 46 for its part fits against the wedge's 45 outer end. Wedge 45 and the first screw 46 here form a friction lock, through which the inner bearing housing 42 is locked to the outer bearing housing 41 against motion in the peripheral direction and in the axial direction. Wedge 45 and the first screw 46 allow step-less control of the inner bearing housing 42 both in the peripheral direction and in the axial direction in relation to the outer bearing housing 41. The bearing structure 40 is mounted to a beam in the lift bogie's body structure with axial bolts 50 extending through the outer bearing housing's 41 flange 41c.
Figure 5 is a side view of the bearing structure in Figure 4, and Figure 6 shows the inner bearing housing of the bearing structure in Figure 5. It can be seen in Figure 5 how the wedge 45 fits against the outer periphery of the inner bearing housing 42, whereby the inner bearing housing 42 is locked into the outer bearing housing 41. Figure 6 shows the eccentric structure of the inner bearing housing 42. The midpoint of the inner periphery 42a of the inner bearing housing 42 and the midpoint of the outer periphery 42a of the inner bearing housing 42 are at a distance E from each other. When the inner bearing housing 42 is rotated in the peripheral direction in the first bore 41a of the outer bearing housing 41, the midpoint of the inner periphery 42a of the inner bearing housing 42 will move in relation to the midpoint of the first bore 41 a of the outer bearing housing 41 in a way determined by the eccentricity.
Figure 7 shows an exploded view of another bearing structure according to the invention. The bearing structure 40 shown in Figure 7 differs from the bearing structure shown in Figure 4 as regards the friction lock between the inner bearing housing 42 and the outer bearing housing 41. In this embodiment, a slot 41c is formed in the outer bearing housing 41 to receive a rocker arm 47. In the first end of the rocker arm 47 there is an axial third bore 47b forming a pivot, and the rocker arm 47 is mounted with a bushing 48a extending through the pivot 47b and with a second screw 48b into the axial first bore 41b formed in the outer bearing housing 41. In the rocker arm's 47 second opposite end there is a fourth bore 47c, which is in a transverse direction in relation to the axial direction and through which a third screw 49 extends, with which rocker arm 47 can be tightened against the outer periphery 42b of the inner bearing housing 42. The curved friction surface 47a of rocker arm's 47 middle part fits against the outer periphery 42b of the inner bearing housing 42. Here rocker arm 47 and the third screw 49 form a friction lock, through which the inner bearing housing 42 is locked into the outer bearing housing 41. The bearing structure 40 is mounted to a beam in the lift bogie's body structure with axial bolts 50 extending through the outer bearing housing's 41 flange 41c, that is, in the same manner as in the embodiment shown in Figure 3.
In the embodiments shown in Figures 4 and 7, the friction lock between the inner bearing housing 42 and the outer bearing housing 41 is formed by a member 45, 47, which is supported to move in the outer bearing housing and whose friction surface 45a, 47a fits against the outer periphery 42b of the inner bearing housing 42 to form said friction lock. The friction lock principle is to form a sufficiently powerful contact force between the outer 41 and the inner 42 bearing housings to prevent the inner bearing housing 42 from moving in relation to the outer bearing housing 41. In the embodiment shown in Figure 4, the mounting member, that is, the first screw 46, presses wedge 45 against the inner bearing housing 42, and in the embodiment shown in Figure 5, the mounting member, that is, the second screw 49, presses lever arm 47 against the inner bearing housing 42. From the embodiments shown in Figures 4 and 7 it is of course possible within the scope of the invention to form various variations, wherein the inner 42 and the outer 41 bearing housings are locked to each other using only the friction surface and a sufficiently powerful contact force directed against the friction surface.
In the solution according to the invention, only the inner bearing housing 42 is eccentric.
The solution according to the invention is especially suitable in a lift bogie moving with metal wheels on rails, but it can also be used in a lift bogie moving with rubber wheels.
The aligning process for the lift bogie's travelling wheels 20 consists of a preset control, which a performed already in the assembly stage, and of a final control following after the erection of the lift bogie. When the control after erection is successful, there is hardly any need for re-control.
The eccentricity of the bearing structure located outside the travelling wheel in the axial direction can be located so that control of the eccentricity will mainly affect in the vertical direction, and the eccentricity of the bearing structure located inside the travelling wheel in the axial direction can be located so that control of the eccentricity will mainly affect in the horizontal direction. Then rotation in the peripheral direction of the inner bearing housing of the bearing structure located outside the travelling wheel will affect the travelling wheel's inclination, and rotation in the peripheral direction of the inner bearing housing of the bearing housing located inside the travelling wheel will affect the travelling wheel's travelling alignment.
The shape of the outer bearing housing 41 and the shape of the end of beam P in the lift bogie's body structure as shown in the figures contribute to the effect that the jacking height will be kept at a minimum when the travelling wheel 20 is exchanged or its position is adjusted.

Claims

Mounting and control solution for a lift bogie's travelling wheel (20), which comprises an outer bearing housing (41), which is supported on the lift bogie's body structure (P), a cylindrical inner bearing housing (42), which is fitted in an axial first bore (41a) of the outer bearing housing (41), and a bearing element (43), through which the travelling wheel's (20) shaft (10) is supported in the inner bearing housing (42), whereby the inner periphery (42a) of the inner bearing housing (42) is eccentric in relation to the outer periphery (42b) of the inner bearing housing (42), characterized in that that the inner bearing housing (42) is locked into the outer bearing housing (41) with a friction lock (45, 46, 47, 49) in such a way that the inner bearing housing (42) can be rotated step-lessly in the peripheral direction in order to control the desired eccentric position in relation to the outer bearing housing (41) and it can be moved step-lessly in the axial direction in relation to the outer bearing housing (41) in order to control the desired gauge.
Mounting and control solution for a travelling wheel according to claim 1, characterized in that the friction lock (45, 46, 47, 49) between the inner bearing housing (42) and the outer bearing housing (41) is formed by a member (45, 47), which is supported to move in the outer bearing housing (41) and whose friction surface (45a, 47a) fits against the outer periphery (42b) of the inner bearing housing (42) to form said friction lock.
Mounting and control solution for a travelling wheel according to claim 1 or 2, characterized in that the friction lock (45, 46, 47, 49) between the inner bearing housing (42) and the outer bearing housing (41) can be opened and closed with one mounting member (46, 49).
Mounting and control solution for a travelling wheel according to any claim 1 - 3, characterized in that the friction lock of the inner bearing housing (42) comprises a second bore (41b), which extends through the outer bearing housing (41) in a transverse direction to the axial direction and which is provided with an internal thread, a wedge (45) fitted in the second bore (41b) and a first screw (46), whereby tightening of the first screw (46) will force the wedge's (45) oblique wedge surface (45a) against the outer periphery (42b) of the inner bearing housing (42) to lock the inner bearing housing (42) in the outer bearing housing (41) against axial and peripheral motion.
Mounting and control solution for a travelling wheel according to any claim 1 - 3, characterized in that the friction lock of the inner bearing housing (42) comprises a lever arm (47), whose first end is supported through a pivot (41b) in the outer bearing housing (41), and whose second opposite end is supported with a second screw (49) in the outer bearing housing (41), whereby tightening of the second screw (49) will force the friction surface (47a) of the lever arm's (47) middle part against the outer periphery (42b) of the inner bearing housing (42) to lock the inner bearing housing (42) in the outer bearing housing (41) against axial and peripheral motion.