GB2156940A

GB2156940A - Adjustable structural joint

Info

Publication number: GB2156940A
Application number: GB08508429A
Authority: GB
Inventors: Rainer Horbach
Original assignee: Mannesmann AG
Current assignee: Vodafone GmbH
Priority date: 1984-04-04
Filing date: 1985-04-01
Publication date: 1985-10-16
Also published as: FR2562530B3; IT8520205A0; GB2156940B; GB8508429D0; FR2562530A1; DE3412551C1; IT1184371B

Abstract

First and second structural members of the trolley of a travelling bridge crane are connected together by an adjustable joint comprising first and second plates (2, 2a), and a plurality of fixing members which may comprise bolts (7) and nuts (8). The first and second plates (2, 2a) are fixed, in use, respectively to the first and second structural members. The fixing members are such as to connect the two plates (2, 2a) in a spaced relationship. At least one spacing sleeve (3, Fig. 4) surrounding an associated bolt (7, Fig. 4) threadably engages one of the plates (2, Fig. 4), abuts the other plate (2a, Fig. 4), and is axially adjustable relative to said one plate. The spacing sleeve (3) may be connected to a rotary disc (6) via pins (5). Convex washers (4a) surrounding the bolts (7) may be interposed between the plates (2, 2a). <IMAGE>

Description

SPECIFICATION Joint This invention relates to a joint for connecting the structural members of the trolley of a travelling bridge crane.

Typically, the trolley of a travelling bridge crane has a bridge girder secured, at its ends, to end girders provided with running wheels. The bridge girder is provided with an attachment plate at each end thereof, the attachment plates being fixed to similar attachment plates associated with the end girders. The running wheels are mounted on blocks which are also fixed to the end girders by similar pairs of attachment plates. A problem connected with the manufacture of a crane of this type, is that of ensuring that manufacturing tolerances are complied with during the construction of the end girders, and their attachment to the bridge girder.

In a known travelling bridge crane, the attachment plates are provided with bores surrounding the connection bolts. The bores contain tubular sleeves which define a reference plane for the parts to be connected. Unfortunately, the tubular sleeves need to be positioned with a high degree of accuracy.

Moreover, connections made in this way are not adjustable.

The aim of the invention is to provide an improved joint for connecting the structural members of the trolley of a travelling bridge crane, and in particularto provide a joint which is adjustable and of low cost.

The present invention provides a joint for connecting first and second structural members of the trolley of a travelling bridge crane, the joint comprising first and second plates and a plurality of fixing members, the first and second plates being fixed, in use, respectively to the first and second structural members, the fixing members being such as to connect the two plates in a spaced relationship, wherein at least one fixing member threadably engages one of the plates, whereby said at least one fixing member is axially adjustable relative to said one plate.

The threading is preferably provided on the plate which is fixed to the smaller structural member, and can be produced with a simple thread-cutting device. Then, the trolley can be assembled on site, the two end girders of the trolley being set upon the rails, and the bridge girder being held therebetween. by introduction of the adjustable fixing members, the end girders can be aligned satisfactorily, and the joints connecting the bridge girder to the end girders can be completed by fixing their plates together.

Advantageously, each fixing member includes a bolt and a nut. Preferably, there are four fixing members, two of which are adjustable.

In a preferred embodiment, the or each adjustable fixing member includes a sleeve surrounding the shaft of the associated bolt, said sleeve having a screw-threaded portion at one end which is engageable with a complementary screw-threaded portion formed on said one plate, the end face of the other end of said sleeve engaging the other plate.

The threaded sleeve is preferably screwed wholly into internal threading in said one plate.

Advantageously, said one end of the or each sleeve is rotationaly fixed to a rotary disc positioned between-the head of the associated bolt and said one plate. Preferably, the or each sleeve is rotationally fixed to the associated rotary disc by means of a pair of pins extending from said rotary disc into a pair of blind bores formed in said one end of that sleeve. The or each rotary disc also serves as a washer for the head of the associated bolt. With the associated nut slightly tightened on its bolt, it is possible to turn the or each rotary disc (and, by means of its pins, the associated fixing member), for satisfactory abutment on the other plate. The adjustment facility of the or each adjustable fixing member could, alternatively, be a screwdriver slot, into which a screwdriver can be introduced for the adjustment of that member.

The or each non-adjustable fixing member may include a washer which is positioned between the two plates, said washer(s) determining the spacing between said plates. Advantageously, the or each washer has a convex surface at one side thereof, said convex surface being received in a complementary concave surface formed in one of said plates.

Preferably, the or each adjustable fixing member includes a washer positioned between said plates, the or each washer having a convex surface on one side thereof, said convex surface being received in a complementary concave surface formed in said other end face of the associated sleeve. The provision of the domed surfaces of washers helps to avoid edge pressures in the case of uneven support.

The invention also provides a trolley for a travelling bridge crane, the trolley comprising a pair of end girders interconnected by a bridge girder, the end girders being provided with running wheels, each running wheel being supported by a respective running wheel block, each of the running wheel blocks being connected to the associated end girder by a joint, and the bridge girder being connected to the end girders by joints, wherein each of the joints is as defined above.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which: Fig. lisa perspective view of an end girder of a travelling bridge crane; Fig. 2 is a perspective view of a running wheel block of a travelling bridge crane; Fig. 3 is a cross-section through a joint for the end girder of Fig. 1 orforthe block of Fig. 2, the cross-section being taken on the line Ill-Ill of either Fig. 1 or Fig. 2; and Fig. 4 is a cross-section similar to that of Fig. 3, but taken on the line IV-lV of either Fig. 1 or Fig. 2.

Referring to the drawings, Fig. 1 shows an end girder 1 of the trolley of a travelling bridge crane.

The girder 1 is provided with a drive motor and two wheels (not shown); and has, on one side, a plate 2 for attachment to a bridge girder (not shown).

Fig. 2 shows a road wheel block la of the trolley of a travelling bridge crane. The block 1 a consists of a housing for a running wheel, and is provided with a plate 2 for attachment to an end girder of the trolley.

The plate 2 of either the end girder 1 or the running wheel block 1 a forms part of the joint which is the subject of the invention. This joint (see Figs. 3 and 4) includes the plate 2, a similar attachment plate 2a fixed to a structural member (not shown) of the trolley of a travelling bridge crane. Where the plate 2 is fixed to an end girder 1, the attachment plate 2a could be fixed to a bridge girder; whereas, where the plate 2 is fixed to a running wheel block 1a,the attachment plate 20 could be fixed to an end girder. The plates 2 and 2a of the joint are detachably connected together by four fixing members, two of which are as shown in Fig. 3, the other two being as shown in Fig. 4.

The fixing member shown in Fig. 3 is constituted by a bolt 7, a nut 8, and a simple washer 4. The washer 4 has a domed surface 4a which extends into a complementary concave surface 4b formed in the plate 2.

The fixing member shown in Fig. 4 is constituted by a bolt 7, a nut 8, and a sleeve 3. The sleeve 3 is formed with a screw thread 3a which engages a complementary thread of the plate 2 whereby the sleeve is adjustable relative to the plate 2. The sleeve 3 has a central bore 3b, which surrounds the shaft of the bolt 7, and two bores 3c for receiving a pair of pins 5 which are fixed to a rotary discS surrounding the shaft of the bolt adjacent to its head. The rotary disc 6 can, therefore, be turned to rotate the sleeve 3, and hence to adjust the sleeve axially with respect to the plate 2.

As shown in the upper half of Fig. 4, the sleeve 3 may be such that its end face abuts the attachment plate 2a. Alternatively, as shown in the lower half of Fig. 4, the fixing member may be provided with a washer 4 of the type shown in Fig. 3. The washer 4 has a domed surface 4a which engages within a complementary concave surface 4b formed in the sleeve 3. This alternative arrangement avoids edge pressures, even where large inaccuracies occur in positioning the parts of the fixing member.

Claims

1. A joint for connecting first and second structural members of the trolley of a travelling bridge crane, the joint comprising first and second plates and a plurality of fixing members, the first and second plates being fixed, in use, respectively to the first and second structural members, the fixing members being such as to connect the two plates in a spaced reiationship, wherein at least one fixing member th readably engages one of the plates, whereby said at least one fixing member is axially adjustable relative to said one plate.

2. A joint as claimed in claim 1, wherein each fixing member includes a bolt and a nut.

3. A joint as claimed in claim 1 or claim 2, wherein there are four fixing members, two of which are adjustable.

4. Ajoint as claimed in claim 2, or in claim 3 when appendant to claim 2, wherein the or each adjustable fixing member includes a sleeve surrounding the shaft of the associated bolt, said sleeve having a screw-threaded portion at one end which is engageable with a complementary screwthreaded portion formed on said one plate, the end face of the other end of said sleeve engaging the other plate.

5. A joint as claimed in claim 4, wherein said one end of the or each sleeve is rotationally fixed to a rotary disc positioned between the head of the associated bolt and said one plate.

6. Ajoint as claimed in claim 5, wherein the or each sleeve is rotationally fixed to the associated rotary disc by means of a pair of pins extending from said rotary disc into a pair of blind bores formed in said one end of that sleeve.

7. Ajoint as claimed in any one of claims 1 to 6, wherein the or each non-adjustable fixing member includes a washer which is positioned between the two plates, said washer(s) determining the spacing between said plates.

8. A joint as claimed in claim 7, wherein the or each washer has a convex surface at one side thereof, said convex surface being received in a complementary concave surface formed in one of said plates.

9. A joint as claimed in claim 4, or in any one of claims 5 to 8 when appendant to claim 4, wherein the or each adjustable fixing member includes a washer positioned between said plates, the or each washer having a convex surface on one side thereof, said convex surface being received in a complementary concave surface formed in said other end face of the associated sleeve.

10. A joint for connecting two structural members of the trolley of a travelling bridge crane, the joint being substantially as hereinbefore described with reference to, and as illustrated by, the accompanying drawings.

11. A trolley for a travelling bridge crane, the trolley comprising a pair of end girders interconnected by a bridge girder, the end girders being provided with running wheels each running wheel being supported by a respective running wheel block, each of the running wheel blocks being connected to the associated end girder by a joint, and the bridge girder being connected to the end girders by joints, wherein each of the joints is as claimed in any one of claims 1 to 10.