GB2250568A

GB2250568A - Securing drive shaft parts together for transport

Info

Publication number: GB2250568A
Application number: GB9124687A
Authority: GB
Inventors: Harald Papke
Original assignee: GKN Cardantec International GmbH
Current assignee: GKN Driveline International GmbH
Priority date: 1990-12-06
Filing date: 1991-11-19
Publication date: 1992-06-10
Also published as: SE9103575L; DE4038882C2; DE4038882A1; ITMI913099A0; IT1252287B; GB9124687D0; FR2670186A1; SE9103575D0; ITMI913099A1

Abstract

A drive shaft having two relatively movable parts 11, 12 e.g. connected by a sliding spline assembly, has sheet metal elements 18, 19 provided on the two parts for connection by securing wire to prevent the shaft parts moving relative to one another in transport or storage, the elements 18, 19 also constituting balancing weights for the shaft. <IMAGE>

Description

22505.58 Title: SECURING DRIVE SHAFT PARTS TOGETHER FOR TRANSPORT

Desgiption of Invention This invention relates to a drive shaft which has at least two shaft parts which move relative to one another in use, and which, for transport and/or storage purposes, are arranged to be secured to one another to prevent said relative movement, by connecting means provided on the exterior of the shaft parts.

Drive shafts of the kind to which the invention relates may be used, for example, in motor vehicle drive lines for power transmission to the drivable wheels of the vehicle. To accommodate the movement of the wheels relative to the vehicle structure, permitted by the vehicle's suspension, each drive shaft must provide for a change in its length between its two ends. This may be achieved by incorporating in each shaft a sliding splined connection, with two parts of the shaft having a torque transmitting connection between them, to permit relative axial movement therebetween, by inter-engaging axially extending teeth. When a shaft is installed in the vehicle, it is connected such that the relative movement possible between the two parts of the shaft is insufficient to disconnect such parts. However, for the purpose of transporting shafts from the place of their production to the place at which they are assembled in vehicles, the two parts of each shaft have to be connected to one another to prevent them from being pulled apart unintentionally. Such connection is also required during storage of shafts.

A connecting arrangement is known from DE-A-2156513 in which two pipeline parts joined by a bellows are connected to one another by a rope extending across the join. However, such an arrangement is complex and expensive, and cannot readily be used for drive shafts for vehicles.

It is the object of the present invention to provide a means for securing relatively movable drive shaft parts against such movement during transport or storage, which means may be produced easily and costeffectively.

2 According to the present invention, we provide a drive shaft comprising two parts which move relatively to one another in use and which are arranged to be secured to one another so as to prevent said relative movement for transport and/or storage purposes, wherein said parts are provided on their exterior with respective connecting means in the form of sheet metal elements which are adapted to be connected to one another by securing wires and constitute balancing weights.

In this way, it is possible to provide a means which offers security of the shaft parts during transport, by wiring the sheet metal elements together, and which, after a shaft is installed, may be left in position on the shaft to fulfil their other function as balancing weights.

In manufacture of a drive shaft, after a shaft has been run in a balancing machine, the sheet metal elements are attached to it, e.g. by projection welding, in the required positions. The sheet metal elements, which from the point of view of their weight are designed in accordance with the statistical mean value of out-of-balance found in the shafts, then additionally serve as the means for securing the shaft parts together. There is no need for any design changes in the individual parts, and the production process may cost-effectively be integrated into existing production lines. The relatively movable parts of the shaft may be secured to one another at the balancing bench, and, since in the case of a sliding spline assembly the two parts are held in the position of maximum insertion of the one part into the other, there is no need for protecting the exterior of the inner part of the spline assembly against paint spray when the shaft is subsequently painted. Nor is then any need for any additional work on the coat of paint applied. If a shaft is repaired, the sheet metal elements may be re-used for securing the parts against relative movement, simply by applying new securing wire. The risk of injury when an operator is welding on flat material and subsequently separating the ends is avoided.

The sheet metal elements are preferably disposed in pairs, the elements of each pair being opposite each other (in axial alignment with each 3 other) on the shaft parts which are to be connected. In accordance with usual shaft-balancing procedures, the sheet metal elements may be selected from a range of such elements of different masses.

As markers, to indicate, for example, the orientation at which a shaft should be installed, or the disposition of associated universal joints, one or more of the sheet metal elements may carry information markings e. g. lettering or numbering, or at least one of the sheet metal elements may have an information carrier such as a plastic capsule associated therewith.

To ensure accurate running of a shaft, it may be precision balanced by the attachment of balancing weights additional to the sheet metal elements according to the invention.

When the sheet metal elements on the shaft parts are connected to one another by securing wire, such wire may provide an electrically conductive connection between the two shaft parts. This is significant if the finished shafts are painted electrostatically, and an electrically insulating element exists between the two shaft parts, e.g. a plastics coating on a sliding spline assembly.

Although the invention is primarily applicable to a drive shaft wherein the two parts are connected to one another by a sliding spline assembly for relative axial movement, it is also applicable to shaft parts connected by other means for the same or other types of relative movement.

The invention will now be described by way of example with reference to the accompanying drawings, of which:- Figure 1 is an elevation, partly sectioned, of a drive shaft to which the invention may be applied; Figure 2 is a section through part of a shaft as Figure 1, according to the invention:

plane; Figure 3 is a plan view of the shaft part of Figure 2; Figure 4 is a view of the shaft part of Figure 2 in a different balancing 4 Figure 5 is a view of shaft parts after the securing wire has been removed; Figure 6 is a section through a shaft having a marker device associated with one of the sheet metal elements according to the invention.

Referring firstly to Figure 1 of the drawings, the drive shaft there illustrated comprises a first shaft part 11 and a second shaft part 12. At opposite ends of the shaft, each shaft part has a Hookes universal joint 16 connected thereto, the joints having drive flanges 16a for bolted connection to the required drive line parts of a motor vehicle. The two shaft parts 11, 12 are connected to one another, for torque transmission and relative axial movement, by a sliding spline assembly. The first shaft part 11 has a connecting piece 13 which reduces in diameter to a sleeve 15 which has internal longitudinally extending teeth. The shaft part 12 comprises a stub shaft with external longitudinally extending teeth engaging the teeth in the sleeve 15 for torque transmission, and a collar 14 spaced from the stub shaft to extend over the sleeve 15, and having a seal at its open end, engaging the external surface of the sleeve 15.

As shown in Figure 2, the shaft part 11 and connecting piece 13) are firmly joined to one another, by a weld 17. In the region of the connecting piece 13, the first shaft part 11 is provided with a sheet metal element 18. The second shaft part 12 is provided on the collar 14 with a second sheet metal element 19 disposed opposite (in axial alignment with) the sheet metal element 18. The elements 18, 19 are connected to one another by a securing wire 20 whose ends are twisted together.

The lower half of Figure 2 shows alternative positions at which the sheet metal elements are attached to the two relatively movable shaft parts. A sheet metal element 18a is connected to the shaft part 11 at a greater distance from the sleeve 15, while a sheet metal element 19a is connected to the collar 14 at a position closer to the associated universal joint 16. Thus the sheet metal elements 18a, 19a are at a greater distance from one another than the elements 18, 19 as shown in the upper half of Figure 1. A longer securing wire 20a is thus required to join the sheet metal elements.

Figures 3 and 4 show the sheet metal elements 18, 19 and 18a, 19a, respectively. Such elements are connected to the external surface of the shaft parts 11 and 12 by welding points 23, e.g. projection welds. The weights of the elements 18, 18a, 19, 19a may be different from one another, the appropriate elements being selected from a range thereof and applied to the shaft parts in accordance with the shaft out-of-balance which is to be corrected, as determined when the shaft is set up on a balancing machine at a late stage of its manufacture.

In manufacture of shafts, it is common for them to be painted after they have been balanced. Because one of the engaging parts of a sliding spline assembly may have a plastics coating, and because of the non-metallic nature of the seal accommodated in the collar 14, the two relatively movable shaft parts may be electrically insulated from one another. If the painting process is carried out electro-statically, the electrical connection which may be established by the securing wires 20, 20a between the relatively movable shaft parts assists such painting process.

As shown in Figure 5, the securing wires may be removed after the drive shaft has been finally assembled in a vehicle. The sheet metal elements 18, 19 then constitute balancing weights to correct for any out-ofbalance in the shaft. If any repair work is needed, the sheet metal elements may be once again connected to each other by new securing wires, allowing the drive shaft to be transported in a secured condition, so that the sliding spline assembly will not come apart.

As shown in Figure 6, the sheet metal elements, in this case the elements 18a for example, are designed in such a way that a plastic element or capsule 22 containing any required information may be clamped into the aperture 21 afforded by the element. Alternatively, the sheet metal elements may themselves carry lettering or other markings.

6 If required for precise balancing of the shaft, balance weights additional to the sheet metal elements providing for connection of the relatively movable shaft parts may be provided.

The features disclosed in the foregoing description, or the following claims, or the accompanying drawings, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

7

Claims

1. A drive shaft comprising two parts which move relatively to one another in use and which are arranged to be secured to one another so as to prevent said relative movement for transport and/or storage purposes, wherein said parts are provided on their exterior with respective connecting means in the form of sheet metal elements which are adapted to be connected to one another by securing wires and constitute balancing weights.

2. A drive shaft according to Claim 1, wherein the sheet metal elements are disposed in pairs, those in each pair being adjacent to one another on the two shaft parts.

3. A drive shaft according to Claim 1 or Claim 2 wherein the sheet metal elements are selected from a range of such elements of different masses.

4. A drive shaft according to any one of the preceding claims wherein the sheet metal elements are welded to the shaft parts.

5. A drive shaft according to any one of the preceding claims wherein the sheet metal elements are re-usable as connecting means.

6. A drive shaft according to any one of the preceding claims wherein one or more of the sheet metal elements carry information markings.

7. A drive shaft according to any one of Claims 1 to 5 wherein an information carrier is associated with at least one of the sheet metal elements.

8 8. A drive shaft according to any one of the preceding claims wherein balance weights additional to said sheet metal elements are provided on the shaft parts.

9. A drive shaft according to any one of the preceding claims wherein the securing wire provides an electrical connection between the shaft parts.

10. A drive shaft according to any one of the preceding claims wherein said parts are connected by a sliding spline assembly.

11. A drive shaft substantially as hereinbefore described with reference to the accompanying drawings.

12. Any novel feature or novel combination of features described herein and/or in the accompanying drawings.