SE1451296A1

SE1451296A1 - A transport and/or mounting device for bearings

Info

Publication number: SE1451296A1
Application number: SE1451296A
Authority: SE
Inventors: Anders Diksved; Jonas Olgemar; Yvonne Rydberg
Original assignee: Skf Ab
Priority date: 2014-10-30
Filing date: 2014-10-30
Publication date: 2016-02-12
Also published as: WO2016068775A1

Abstract

The invention relates to a transport and/or mounting device for bearings. The transport and/or mounting device comprises a rod extending in a longitudinal direction and has an upper portion, a central portion and a lower portion. An upper member with a protrusion is positioned around the upper portion of the rod and a lower member with a protrusion is positioned around the lower portion of the rod. The longitudinal distance between the upper and lower protrusions can be varied using an adjustment member which is situated on the lower portion of the rod in a longitudinal position below the lower member.

Description

CAGE CLAMPS - 2014EOO277 SEA TRANSPORT AND/OR MOUNTING DEVICE FOR BEARINGS Technical field of the invention The invention relates to a transport and/or mounting device for bearings.The transport and/or mounting device is used to attach two bearing cages toeach other which allows for a fixation of the rolling elements duringtransportation and mounting of a bearing.

BackgroundBearings are used in all types of mechanical applications to provide lower friction between moving parts therein. Today there is a large variationbetween different types of bearings which are suited for different applications.Some bearings are constructed to carry extreme loads, whereas others needto be able to withstand very corrosive environments. Depending on therequirements put on a bearing, different materials and construction types willbe used.

Despite their different uses and constructions one thing which unites all typesof bearings is the basic construction thereof comprising an inner ring, rollingelements, a cage holding or surrounding the rolling elements and an outerring. To ensure that the bearing has a long liftime without failure, it isimportant that all components making upp the bearing have a good fit and arealigned correctly. Missalignment in a bearing will lead to increased friction insaid bearing and in extreme cases to mechanical failure thereof.

When transporting and mounting a bearing there is a large risk that the rollingelements become missaligned due to movements which occur duringhandling of said bearing.

For bearings having more than one parallel row of rolling elements andwherein more than one bearing cage is used to align the rolling elements theproblem is even more accute as it may be impossible to place the bearingsuch that gravity helps maintain the rolling elements in the correct positionduring transportation and mounting. One example of such a bearing type is adouble direction sperical roller thrust bearing (DDSRTB) which has rolling elements placed on the same inner ring and where the rolling elements facetwo different directions.

There is thus a need for a construction which secures that the rollingelements of a bearing remain correctly positioned during transportation andmounting to ensure that optimum performance of the bearing can be achievedwithout extra adjustment of the rolling elements. Specifically there is a need tosecure the rolling elements for bearings which comprise multiple rows ofrolling elements.

Summarv of the inventionlt is a general object of this invention to alleviate the above-mentionedproblems.

According to a first aspect of the invention, there is provided a transportand/or mounting device for bearings wherein said transport and/or mountingdevice comprises a rod extending in a longitudinal direction comprising anupper portion, a central portion and a lower portion, wherein an uppermember with a protrusion is positioned around the upper portion of the rodand a lower member with a protrusion is positioned around the lower portionof the rod, wherein the longitudinal distance between the upper and lowerprotrusions can be varied using an adjustment member and wherein saidadjustment member is situated on the lower portion of the rod in a longitudinalposition below the lower member.

When using a device as described above, it is possible to fix two bearingcages to each other and hold the rolling elements into position duringtransport and during mounting of the bearing into its final use position. Saidfixation amounts to a more secure transportation of the bearing and also itensures that when a bearing is mounted into place all rolling elements remainin the correct position thereby allowing for a bearing with an optimumperfomance. Correct positioning of the rolling elements is essential not only toavoid the friction and wear caused by rolling elements which have slippedfrom their position but also to avoid time consuming adjustment of all rolling elements during mounting of the bearing. Once the bearing has beenmounted into the correct position, the transport and/or mounting device isremoved and the ro||ing elements are free to rotate around their axis leadingto a fully functioning bearing.

According to one embodiment the transport and/or mounting device has acentral member which is positioned around the rod in the central portion andsituated in a longitudinal direction between the upper and lower members. Anadvantage of using a central member is that it provides extra stability to thetransport and/or mounting device. Upon tightening the device when mountingit onto the bearing cages of a bearing the central members providesadditional mechanical stability to the rod and the rod is therefore not benteven though a high force is exerted thereon.

According to one embodiment the inside of the upper member and theexterior surface of the rod in the upper portion are threaded to allow for theupper member to move in a longitudinal direction of the rod when rotatingsaid rod around its longitudinal axis. This specific construction allows for easyadaptation and adjustment of the distance allowing for easy usage of thedevice.

According to one embodiment the adjustment member is permanently fixed tothe rod. This embodiment allows for simple manufacturing and ease ofhandling as the number of movable or adjustable parts is kept at a minimum.

According to one feature of the above embodiment the rod is rotated byturning the adjustment member around its longitudinal axis. When theadjustment member is fixed to the rod the adjustment member is easilyaccessed and can be used to turn rotate the rod and thereby adjust thedistance d1 between the upper and lower members.

According to one embodiment the central member and the lower member areunfixed to the rod such that they can move freely in a longitudinal directionalong the rod. This specific construction allows the central member and thelower member to move freely and adjust to the movement of the uppermember and the rod with the adjustment member as the device is tightened.

According to one embodiment the rod has a cross-section which is circular. Acircular shape allows the lower member to rotate around the rod during thetightening of the device which allows the lower member to follow themovement of the upper member during tightening of the device.

According to one embodiment the protrusions on the upper and lowermembers extend outwards from the rod at a distance of 5 to 10 mm. Thislength is sufficient to allow for the protrusions to grasp into perforationspresent on a bearing cage while at the same time not being too long whichrequires a large space to mount and remove the devices. ln well around thecage preferably they extend outward at a distance of 6 to 7 mm.

According to one embodiment the protrusions have an angle oi as measuredbetween the surface of the protrusion facing the central portion of the rod andthe surface of the rod and wherein said angle oi is from 45° to 90°. Anadvantage is that at 90° angle it is easier to insert the protrusion of the deviceinto the perforations through the rim of the bearing cage. However, whenincreasing the angle up to 45° the protrusion will grip around the edge of theperforation in the bearing cage the angle will also secure that the device doesnot slip out of the perforation as the attachment force thereof is increased.

According to one feature of the above embodiment the angle oi between thesurface of the protrusion and the rod is not the same for the upper protrusionsurface and the lower protrusion surface. Having different angles can providean advantage if there is a specifically challenging situation such as extremelysmall space when attaching or removing the device from the bearing cages.By adjusting the angels differently the device can be adapted to suit eachspecific need.

According to one feature of the above embodiment the angle oi between thesurface of the protrusion and the rod is the same for the upper protrusionsurface and the lower protrusion surface. This feature allows for astandardized solution which is simpler to manufacture and also allows foreasier mounting as the device can be mounted in either direction as bothupper and lower member are identical.

According to a second aspect of the invention there is provided a DoubleDirection Spherical Roller Thrust Bearing (“DDSRTB”) which has an inner ringand on said inner ring two separate cages are present where said cagescomprise windows in which ro||ing elements are present and wherein thecages are attached to each other by a removable transport and/or mountingdevice as defined in any of the embodiments or features above.

Brief description of the drawinqsBy way of example embodiments of the invention will now be described withthe reference to the accompanying drawings in which: Fig. 1 illustrates a steel bearing cage.

Fig. 2 shows a DDSRTB with two steel cages holding the ro||ing elements andwherein the steel cages are attached to one another using cage clamps.

Detailed descriptionln the following detailed description preferred embodiments of the invention will be described. However, it is to be understood that features of the differentembodiments are exchangeable between the embodiments and may becombined in different ways, unless anything else is specifically indicated. ltmay also be noted that, for the sake of clarity, the dimensions of certaincomponents illustrated in the drawings may differ from the correspondingdimensions in real-life implementations of the invention.

The present invention relates to a transport and/or mounting device to beused with roller bearings and will hereafter be described more in detail withreference to Figures 1-2.

Figure 1 shows a transport and/or mounting device 1 for bearings whereinsaid transport and/or mounting device 1 comprises a rod 10 extending in alongitudinal direction. The rod is divided into three sections; an upper portion11, a central portion 12 and a lower portion 13. Around the upper portion 11an upper member 21 with a protrusion 31 is positioned. Around the lower portion 13 of the rod 10 a lower member 23 with a protrusion 33 is positioned.ln the figure a central member 22 positioned around the central portion 12 isalso shown. The central member 22 is not essential for a functioning device 1but it can be an advantage to have said central member 22 as it strengthensthe mechanical properties of the rod 10 allowing the device 1 to be fastenedusing a higher force. ln figure 1 the rod 1 is illustrated with an adjustment member 43 fastenedonto the lower portion 13 of the rod 1 in a longitudinal position below thelower member 23. Although the adjustment member 43 is attached onto therod in the figure it is also possible that the adjustment member 43 is not fixedto the rod 10 but is a threaded bolt which can be moved up and down alongthe rod in a longitudinal direction by a turning action. ln this alternativeembodiment the rod 10 must also be threaded in the lower portion 13.

The upper member 21 has a protrusion 31 which extends radially outwardfrom the rod 10. The lower member 23 has a similar protrusion 33 whichextends radially outward from the rod 10. Each of the protrusions 31,33extends radially outward at a distance d2. ln most instances d2 is chosen to bebetween 5 to 10 mm and preferably the distance d2 is 6 to 7 mm.

The distance d1 between the protrusions 31,33 of the upper 21 and lower 23members can be adjusted using the adjustment member 43. When theadjustment member 43 is fixed onto the rod 10, the adjustment member 43can be rotated around its axis to rotate the rod 10. When the rod is rotated theupper member 21 will rotate around the rod 10. Both the upper member 21and the rod 10 are threaded 41,51. The threads 41,51 of the upper member21 and the rod 10 match each other and when the rod 10 is rotated by turningthe adjustment member 43 the upper member 21 will move in a longitudinaldirection along the rod 10 which leads to an adjustment of the distance d1between the upper 31 and lower 33 protrusions. To avoid the upper member21 from being twisted offthe rod 10 a stopper or cap 71 is used. lt is notnecessary to use a cap 71 to create the stop at the top of the rod 10,alternative ways of creating a stop could be that the threads 41 on the rod 10do not extend all the way to the top of the rod 10 or, alternatively, the top threads are damaged so that the upper member 21 cannot move past the topportion of the rod 10. ln the alternative embodiment when the adjustment member 43 is not fixed tothe rod 10, the turning of the adjustment member 43 will lead to theadjustment member 43 moving in a Iongitudinal direction along the rodthereby altering the distance d1.

The protrusions 31,33 have an angle oi as measured between the surface ofthe protrusion facing the central portion of the rod 61,63 and the surface ofthe rod 10. lt is preferable that the angle d is chosen somewhere between 45°and 90°. ln figure 1 the angle oi between the surface of both protrusions 61,63and the rod 10 is the same but it is also possible that the angles are different.

Figure 2 shows a Double Direction Spherical Roller Thrust Bearing(DDSRTB) 2 without the outer rings attached. For this specific embodimentone central ring 203 is used which has two surfaces angled in differentdirections. On each surface a number of rolling elements 204 are placed andare fitted into the windows 203 of the steel cages 201 ,202 to secure therolling elements 204 in relation to each other. The steel cages 201,202 areattached to each other using mounting and/or transportation devices 1 asdescribed above. The mounting and/or transportation devices 1 are fitted intoperforations 206 situated along the lower rims 208,209 of the steel cages201,202. During use of a roller bearing 2 these devices 1 are to be removedbut they will ensure that all rolling elements 204 are maintained in the correctposition during transportation and mounting thereby ensuring optimumperformance of the roller bearing 2. When using said devices 1 it is notnecessary to manually verify and adjust each rolling element 204 aftertransportation or when the roller bearing 2 is mounted into position for use.

Figure 3 shows a cross-section of a DDSRTB 2 where the connectionbetween the transport and/or mounting device 1 is illustrated. The transportand/or mounting device 1 is placed in the perforations 206 situated along thelower rims 208,209 of the steel cages 201,202. The adjustment member 243has been tightened to reduce the distance d1 and the steel cages 201,202press the rolling elements 204 against the inner ring 203. The pressure will fixate the rolling elements 204 tightly against the inner ring 203 thus blockingthem from any movement during either transportation or mounting of the ro||erbeanng.

Claims

1. A transport and/or mounting device (1) for bearings wherein saidtransport and/or mounting device (1) comprises a rod (10) extending in alongitudinal direction comprising an upper portion (11), a central portion (12)and a lower portion (13), wherein an upper member (21) with a protrusion(31) is positioned around the upper portion (1 1) of the rod (10) and a lowermember (23) with a protrusion (33) is positioned around the lower portion (13)of the rod (10), wherein the longitudinal distance (d1) between the upper (31)and lower (33) protrusions can be varied using an adjustment member (43)and wherein said adjustment member (43) is situated on the lower portion(13) of the rod (10) in a longitudinal position below the lower member (23).

2. A transport and/or mounting device (1) according to claim 1 wherein acentral member (22) is positioned around the rod in the central portion (12)and situated in a longitudinal direction between the upper (21) and lower (23)members.

3. A transport and/or mounting device (1) according to any of claims 1 or2 wherein the inside of the upper member (21) and the exterior surface of therod (10) in the upper portion (11) are threaded (51 ,41) to allow for the uppermember (21) to move in a longitudinal direction of the rod when rotating saidrod around its longitudinal axis.

4. A transport and/or mounting device (1) according to and of thepreceding claims wherein the adjustment member (43) is permanently fixed tothe rod.

5. A transport and/or mounting device (1) according to claim 4 whereinthe rod is rotated by turning the adjustment member around its longitudinalaxis.

6. A transport and/or mounting device (1) according to any of thepreceding wherein the central member (22) and the lower member (23) areunfixed to the rod (10) such that they can move freely in a longitudinaldirection along the rod (10).

7. A transport and/or mounting device (1) according to any of thepreceding claims wherein the rod (10) has a cross-section which is circular.

8. A transport and/or mounting device (1) according to any of thepreceding claims wherein the protrusions (31 ,33) on the upper (21) and lower(23) members extend outwards from the rod at a distance (d2) of 5 to 10 mm,preferably they extend outward at a distance (d2) of 6 to 7 mm.

9. A transport and/or mounting device (1) according to any of thepreceding claims wherein the protrusions (31,33) have an angle oi asmeasured between the surface of the protrusion facing the central portion ofthe rod (61 ,63) and the surface of the rod (10) and wherein said angle oi isfrom 45° to 90°, preferably said angle oi is from 60° to 80°.

10. A transport and/or mounting device (1) according to claim 10 whereinthe angle oi between the surface of the protrusion (61,63) and the rod (10) isnot the same for the upper protrusion surface (61) and the lower protrusionsurface (63).

11. A transport and/or mounting device according to claim 10 wherein theangle oi between the surface of the protrusion (61,63) and the rod (10) is thesame for the upper protrusion surface (61) and the lower protrusion surface (63).

12. A Double Direction Spherical Roller Thrust Bearing (2) where saidbearing (2) has an inner ring and on said inner ring two separate cages (201 ,202) are present where said cages (201,202) comprise windows (203) inwhich rolling elements (204) are present characterized in that the cages(201,202) are attached to each other by a removable transport and/ormounting device (1) as defined in any of claims 1-11.