GB2522891A

GB2522891A - A safety assembly for a vehicle wheel with a flexible binding organ tensionable in two directions

Info

Publication number: GB2522891A
Application number: GB1402191.9A
Authority: GB
Inventors: Albertus Abraham Petrus De Groot
Original assignee: Individual
Current assignee: Individual
Priority date: 2014-02-07
Filing date: 2014-02-07
Publication date: 2015-08-12
Anticipated expiration: 2034-02-07
Also published as: GB201402191D0; GB2522891B

Abstract

A safety assembly for a vehicle wheel comprises a plurality of safety devices for indicating relative rotational displacements between first and second mounting members for mounting the wheel. Each safety device comprises a body having a bore for fitting it onto a second mounting member. The assembly further comprises a flexible elongate binding organ which extends along and between the safety devices for counteracting the second mounting members to rotate in a loosening direction. Each safety device comprises position indicating means for indicating a rotational position of its respective second mounting member. Furthermore each safety device is provided with a guiding path for the binding organ to extend along. The guiding path of each safety device forms interspaced upstream and downstream points of application for the binding organ to get tensioned in both an upstream and downstream direction towards neighboring safety devices during a rotation in the loosening direction thereof. The flexible elongate binding organ may be a rubber band.

Description

Title: A safety assembly for a vehicle wheel with a flexible binding organ tensionable in two directions.

Description

The invention relates to a safety assembly for a vehicle wheel, comprising a plurality of safety devices for indicating relative rotational displacements between first and second mounting members, in particular wheel studs and wheel nuts, for mounting the wheel to a vehicle, in which each safety device comprises a body having a bore with a central axis for filling it onto a respective second mounting member, and position indicating means for indicating a rotational position of said respective second mounting member.

Vehicle wheels are typical hub mounted by means of wheel studs and wheel nuts.

Forces with which those wheel nuts are tightened, clamp the wheel to the hub. Several safety devices have been developed to indicate a possible loosening of the wheel nuts. Such a loosening of wheel nuts is a well-known issue and sometimes may even result in a wheel detachment, especially in the commercial vehicle industry, like busses and trucks.

For example GB 2 242 720 shows a safety indicating device which comprises a cylindrical body which delimits a grooved internal bore with which it can be slid with a form fit over a hexagonal wheel nut. The plurality of grooves make it possible to slide the safety device in various rotational positions with said form fit over the hexagonal wheel nut. At its outer circumference, the body is equipped with an outwardly projecting pointer. During use the body can be slid over the wheel nut in such a rotational position that the pointer gets to point towards a reference mark on the wheel. It is also possible for a plurality of the safety devices to get positioned such over a wheel nut that their pointers all get to point in a same easily recognizable specific direction, for example all pointing towards a center axis of the wheel or all pointing clockwise or counter-clockwise towards a neighboring safety device.

Thus a visual inspection has easily been made possible in which for example a driver or maintenance worker can quickly see if one or more of the safety devices have started to A disadvantage with this is that such visual checks are only performed periodically. It may even occur that one or more of the wheel nuts have loosened so much in between such periodic visual checks that the wheel can move relative to the hub and thus lead to a large risk for an accident to happen.

GB 2 229 241 discloses a safety assembly which likewise comprises a plurality of internally grooved cylindrical bodies which are designed for being slid with a form fit over a plurality of hexagonal wheel nuts. Here the bodies however are not provided with a pointer or the like. This is not necessary because the bodies have been fixedly connected and anchored to each other by means of tie members. The tie members may be formed as inextensible bars which arc formed integrally with the bodies of the assembly. It is however also possible for the tie members to be formed by inextensible strips which during mounting need to be connected to the bodies. In both cases the tie members serve the purpose to fully anchor the bodies in their rotational positions and thus also fully block the wheel nuts against rotations in their loosening direction.

A disadvantage with this however is that the provision of the tie members makes a mounting or dismounting operation of the assembly over the wheel nuts more difficult. When the tie members are formed as integral rigid bars, all the grooved bodies, during such a mounting or dismounting operation, need to be slid as one assembly over or taken from their wheel nuts in one go because of the rigid bars extending there between. When the tie members are formed as flexible strips, the grooved bodies first need to be placed individually over their wheel nuts. Then the strips need to be connected at fixed anchor points to the bodies, after which the need to be ratchet tight. When it is then necessary to dismount one or more of the grooved bodies again, the strips need to be cut through before they can be disconnected from the bodies again. As soon as the bodies then need to be placed back onto their nuts, new strips need to be connected and securely ratchet to the bodies. All in all this is a time-consuming and difficult operation to perform.

Another important disadvantage with the use of this known safety assembly of GB 2 229 241 with its fully anchored bodies and thus also fully anchored wheel nuts, is that it has appeared that a snapping of wheel studs onto which the wheel nuts are mounted, appeared more frequently compared to those where such a full anchoring did not take place.

The present invention aims to overcome those disadvantages at least partly or to provide a useful alternative solution. In particular the invention aims to provide a flexibly usable and user-friendly safety assembly which can be easily mounted and dismounted from a set of wheel nuts, and which help the user to keep the vehicle in a safe driving mode.

This aim is achieved by a safety assembly for a vehicle wheel which comprises a plurality of safety devices for indicating relative rotational displacements between first and second mounting members for mounting the wheel to a vehicle. The safety devices are of a type in which they each comprise a body with a bore with a central axis for fitting it onto a respective second mounting member. Furthermore, each of the safety devices comprises position indicating means for indicating a rotational position of its respective second mounting member. The assembly further comprises a flexible elongate binding organ which extends along and between the safety devices for exerting a counterforce on the second mounting members when they start to rotate in a loosening direction. According to the inventive thought each safety device is provided with interspaced upstream and downstream points of application which are positioned such along a guiding path for the binding organ to extend along that the flexible binding organ automatically gets tensioned in both an upstream and downstream direction towards neighboring safety devices during a rotation in the loosening direction thereof.

With the upstream and downstream points of application it is meant parts of the safety devices against which the binding organ lies in a mounted position and which are able to start exerting pulling forces to the binding organ in two opposing directions during a rotation of the safety device in its loosening direction.

With this the binding organ in the mounted position each time extends substantially straight from an upstream point of application of a first safety device towards a downstream point of application of a neighboring second safety device, then extends along the guiding path of this second safety device towards its upstream point of application, then extends substantially straight from this upstream point of application of the second safety device towards a downstream point of application of a neighboring third safety device, etc., in order to at last end at the downstream point of application of the first safety device and then extend along the guiding path of this first safety device towards the upstream point of application.

In other words one could also say that the binding organ runs along the plurality of guiding paths of the individual safety devices, while each time lying against two points of application at the ends of those guiding paths. At a downstream side of each safety device, for example the counter-clockwise side when the safety devices are positioned in a circle, the binding organ extends towards a neighboring safety device which lies at this downstream side. At an upstream side, for example the clock-wise side when the safety devices are positioned in a circle, the binding organ extends towards a neighboring safety device which lies at this upstream side.

When one of the safety devices starts to rotate in its loosening direction, then this immediately leads to a pulling force being exerted by both its upstream and downstream points of application onto upstream and downstream parts of the binding organ which extend away from this safety device towards both its neighboring safety devices.

Advantageously the safety assembly can now be equipped with a truly flexible elongate binding organ which does not have to be fixedly connected to anchoring points or the like of the safety devices. It suffices if each safety device comprises a guiding path delimited at its outer ends by the two interspaced points of application, one at a downstream side and one at an upstream side of the guiding path.

Since a rotation of one of the safety devices immediately results in the building up of pulling forces in the binding organ in both the upstream as well as in the downstream direction, this pulling force gets automatically exerted upon both the neighboring safety devices. This is particularly advantageous because then, a slight limited rotation of one of the safety devices in its loosening direction, automatically gets counteracted by pulling forces acting from two sides upon this safety device. This helps to build up a rapidly increasing strong counterforce for counteracting this starting to rotate loose of this one of the safety devices. In addition it at the same time helps to prevent that the neighboring safety devices start to rotate in their loosening directions. Both the neighboring safety devices from that moment on automatically get held stronger in their mounted position. Neither one of the neighboring safety devices all of a sudden gets the full freedom to rotate in its loosening direction.

Surprisingly it has appeared that a snapping of wheel studs (as being the first mounting members) onto which wheel nuts (as being the second mounting members) are mounted, has importantly reduced, both compared to safety devices which fully anchor the wheel nuts as well as compared to safety devices which do not anchor the wheel nuts at all but only make a rotation in their loosening direction visible by means of their pointers.

This positive effect probably has got to do with the fact an advised torque level for screwing the wheel nuts onto the studs, is related to a pre-stretch of the stud, to set a pre-load, all as a benefit of the tightening. Looking at a general loosening process of studs and nuts, two stages can be defined, namely a first loosening stage during which a clamping force remains between the wheel and the hub, and a second loosening stage where no clamping force at all is left.

A test machine according to a so-called Junkers principle" has been used to simulate the loosening. Based on the experiences and tests with this simulation a relation could be extracted between the loosening torque and the fastening torque. In fact there seemed to be some kind of linear relationship between the fastening torque and the loosening torque that can occur, if two plates, simulating the hub and the wheel are forced for relative movement.

These tests show that a higher level of a fastening torque, results in a corresponding higher level of a loosening torque. During the loosening of wheel nuts, the fastening torque has appeared to reduce rapidly, and so did the loosening torque and the stress on the studs.

Retaining the wheel nuts in position under these loosening circumstances -at a certain advised torque level -and thus preventing them from relative rotation, increased stress on the studs by the loosening circumstances, and so the fatigue and wear on the studs. With a test machine simulation of wheel movement, and retaining of wheel nuts fastened relative to a hub, at a torque level as prescribed by a vehicle manufacturer, studs of 22 mm, appeared to snap after a brief period of time.

More tests with a same dimensions of studs and nuts however did show that with lower fastening torques -but still with clamping force -the fatigue of studs did severely reduce. In the second loosening stage, that is to say the one where no clamping force is left, the wheel not only can make some radial movements, but the wheel can even start wobbling.

From there the process of loosening has gotten uncontrolled and rapidly may lead to the nuts getting fully loosened from the studs.

According to the inventive thought advantageous use is made of the insight that in case where the circumstances are such that a wheel can move somewhat relative to a hub and wheel nuts are driven to loosen, it is preferable not to retain those wheel nuts to their studs or to the hub at a relative high fastening torque, but at a lower level of clamping force.

This prevents fatigue but also prevents that the wheel nut loosening moves rapidly into the second stage. According to the invention this can easily be obtained by the binding organs being positioned such that one the one hand they give some freedom for the safety devices and their second mounting means to start rotating over a limited angular rotation, while on the other hand quickly helping to build up rapidly increasing pulling forces in the upstream and downstream binding organ segments in order to counteract a further rotation of the safety devices.

Thus the invention provides an assembly of safety devices which on the one hand does not fully anchor first and second wheel mounting means, but which allows the safety devices to rotate loose up till a managed level, and from there retain those wheel mounting means in place. On the other hand the individual safety devices clearly indicate it if they have started to rotate loose such that a drive or maintenance person can take appropriate action when he detects this during a periodic inspection.

The binding organ can be made out of all kinds of materials, and can be made as an endless loop or be formed by a plurality of segments, and can be made substantially inextensible or elastically extensible. In the case that the binding organ is made substantially inextensible, it needs to be laid with a play of some millimeters in between the safety devices, this play corresponding to a managed level up till which it is foreseen to have the second wheel mounting means rotate loose before starting to more forcedly retain them in place.

In a preferred embodiment however, the binding organ is formed by a rubber band.

The extensible rubber binding organ offers both elasticity and strength thereto. This makes it well possible to control the amount of initial acceptable loosening, such that the second mounting means has the freedom to come loose till a certain level, while still enough clamping force is left. This prevents that the clamping force remains too high, which would otherwise shorten the period till the mounting means gets to break because of fatigue. Also it helps to prevent the wheel from wobbling, because of the level of clamping force which is left. This will prevent unsafe characteristics of the vehicle and detachment of the wheel from the vehicle in a short period of time.

The rotational positions of the points of application of two neighboring safety devices preferably is such that a distance in between linking upstream and downstream points of application of such neighboring safety devices, immediately and automatically becomes longer when one of those neighboring safety devices starts to rotate in its loosening direction. This has the effect that the upstream and downstream parts of the binding organ automatically get tensioned because they have to span larger distances. The larger those distances become, the larger the counteracting forces against the second mounting means rotating loose further becomes. In particular a rotation of one of the safety devices in its loosening direction will easily be able to enlarge a total length of the binding organ with 5-15%.

Further preferred embodiments are stated in the dependent subclaims.

The invention also relates to a safety device for use in a safety assembly, as well as to a method for using a safety assembly.

The invention shall now be explained in more detail with reference to the accompanying drawings, in which: -Fig. 1 a, b show two perspective views of a first embodiment of safety device according to the invention; -Fig. 2 show a schematic top view of a safety assembly configuration with the safety devices of fig. 1 mounted to a vehicle wheel; -Fig. 3a, b, c, d, e show three perspective views, a cross-sectional perspective view, and a top view of a second embodiment; -Fig. 4 shows a schematic top view of a safety assembly comprising the safety devices of fig. 3 mounted to a vehicle wheel; -Fig. 5 shows a perspective view of a third embodiment; -Fig. 6 shows a schematic top view of a safety assembly comprising the safety devices of fig. 5 mounted to a vehicle wheel; -Fig. 7 shows a perspective view of a fourth embodiment; and -Fig. S shows a schematic top view of a safety assembly comprising the safety devices of fig. 7 mounted to a vehicle wheel.

In fig. 1 the entire safety device is giver the reference numeral 1. The device 1 comprises a cylindrical body 2 which has a downwardly open internal bore 3 with a central axis of rotation Y. The bore 3 is dimensioned and/or profiled such (not shown here) that it can be placed with a form fit over a hexagonal shaped wheel nut, bolt or the like. At its upper side the body 2 is provided with an integrally formed hood 2. A nose part 4 is provided which projects radially outwardly from the body 2. The nose part 4 forms position indicating means which by pointing in a certain direction indicate a rotational position of the device 1.

The nose part 4 comprises a gutter shaped guiding path 5. This guiding path 5 forms a hook at the nose part 4. At a free outer end of the nose part 3 a so-called upstream point of application 7 is formed. At a transition of the nose part 4 with the body 2, a so-called downstream point of application 8 is formed.

As can be seen in fig. 2, an endless, closed loop, ring-shaped rubber binding organ 9 can be suitably and easily hooked behind the nose parts 4 of a plurality of safety devices 1 such that it gets to extend freely along the guiding paths 5 thereof while lying against the points of application 7, 8. The guiding path 5 is open towards a lower side of the nose part 4 such that the binding organ 9 can freely be placed therein from below.

In fig. 2 the safety devices 1 have been fit over a set of tightened wheel nuts (not shown) in such an orientation, referred to as the mounting position, that they get to point with their nose parts 4 to their upstream neighboring safety device 1, that is to say the safety device 1 which lies at their clockwise side. In this position the binding organ 9 extends with relative short lengths U in between upstream point of application 7 of one safety device 1 and a downstream point of application 8 of another neighboring safety device 1. With this the entire binding organ 9 gets to extend inwardly along the center axis of rotation Y of the safety devices 1.

Because of the elasticity of the rubber organ 9, the safety devices 1 in those original mounting positions may already have clockwise rotational forces exerted thereon which holds them in their mounting positions.

As can be seen in the enlarged partial view of fig. 2, should one of the safety devices ii rotate over an angle ci in a counter-clockwise loosening direction, then this immediately results in the original lengths Li getting stretched. At its downstream side a binding organ segment 9d gets stretched to a longer length Li'. At its upstream side a binding organ segment 9u gets stretched to a longer length Li ". Those increasing lengths result in a buildup of a higher counterforce being exerted on the safety device to not rotate further in the loosening direction. The more the safety device ii tries to rotate loose, the more the binding organ segments 9d, 9u get stretched, and the more they shall exert pulling forces on the application points 7, 8.

In fig. 3 a variant is shown in which a guiding path 35 in between an upstream point of application 37 and a downstream point of application 38 extends along a nose part 34 and along a part of the circumference of a body 32 of a safety device 31. Both the upstream and downstream points of application 37, 38 here are formed as hooks behind which a binding organ 39 can be hooked. The guiding path this time is open towards the upper side of the body 31 such that a binding organ 39 can freely be placed therein from above.

In fig. 4 the safety devices 31 have been fit over a set of tightened wheel nuts (not shown) in such an orientation, referred to as the mounting position, that they get to point in pairs towards each other. With this a downstream binding organ segment 39d of a first downstream safety device 31d of the pair gets to extend inwardly along a center axis of rotation Yd of this safety device 31d, whereas an upstream binding organ segment 39u of a second upstream safety device 31 u of the pair gets to extend outwardly along a center axis of rotation Yu of this safety device 31 u.

As can be seen in the enlarged partial view of fig. 4, should one of the safety devices 31 i rotate over an angle in a counter-clockwise loosening direction, then this immediately results in both the segments 39d and 39u getting stretched. This results in higher counterforces being exerted on the safety device 31 ito not rotate further in the loosening direction.

It is noted that in fig. 3d it can be seen that a bore 33 inside the body 32 is provided with a set of axially extending interspaced grooves 41. Those grooves serve the purpose of forming a form fit with for example a hexagonal shaped nut or bolt as mounting means.

Furthermore it is noted that in fig. 3c it can be seen that the body 32 is provided with outlet openings 42. Those outlet openings 42 serve the purpose of swinging water which may have accumulated inside the body 32, to the outside during rotation of a vehicle wheel to which the safety device 31 is mounted.

In fig. 5 another variant is shown in which a guiding path 55 in between an upstream point of application 57 and a downstream point of application 58 extends along a nose part 54 and along a part of the circumference of a body 52 of a safety device 51. Only the downstream point of application 58 here is formed as a hook behind which a binding organ 59 can be hooked. The nose part 54 this time is not equipped with a hook, instead a central gutter shaped guiding path 55 is provided in the nose pad 54. The guiding path is open towards the upper side of the body 51 such that a binding organ 59 can freely be placed therein from above. Fig. 6 shows the advantageous operation of this variant, which is substantially the same as in fig. 4.

It is noted that the device 51 advantageously has been made symmetrical such that it can be used in a similar manner in combination with mounting means with clockwise loosening directions. In that case a binding organ can be laid into the guiding path 55' which in the fig 5 lies at the right side of the center axis Y opposite the above mentioned guiding path 55.

In fig. 7 another variant is shown in which a guiding path 75 in between an upstream point of application 77 and a downstream point of application 78 extends symmetrically through a nose part 74. With this the guiding path 75 also extends through a hood 72' of a body 72 of a safety device 71. Both the downstream and upstream points of application 77, 78 here are formed at a transition of the nose part 74 with the body 72. The guiding path 75 is open towards the upper side of the body 71 such that a binding organ 79 can freely be placed therein from above. Fig. 8 shows the advantageous operation of this variant. As can be seen, the safety devices 71 this time in the mounting position point radially inwards. A counter-clockwise rotation of one of the safety devices 71 immediately leads to both an upstream and a downstream segment of the binding organ 79 getting stretched and thus tensioned.

Besides the embodiments shown, numerous variants are possible. For example the dimensions and shapes of the various components can be varied. Preferably the device is made out of plastic. Other materials however are also possible.

Thus the invention provides an economic to manufacture safety device which can easily be mounted and dismounted onto or from a set of vehicle wheel nuts or bolts in such a manner that a limited rotating loose of the wheel nuts or bolts is not fully blocked but is allowed up to a certain extent.

Claims

CLAIMS1. A safety assembly for a vehicle wheel, comprising: -a plurality of safety devices for indicating relative rotational displacements between first and second mounting members for mounting the wheel to a vehicle, in which each safety device comprises a body having a bore with a central axis for fitting it onto a respective second mounting member; -a flexible elongate binding organ extending along and between the safety devices for counteracting the second mounting members to rotate in a loosening direction, characterized in that, each safety device comprises position indicating means for indicating a rotational position of its respective second mounting member, and each safety device is provided with a guiding path for the binding organ to extend along, wherein the guiding path of each safety device forms interspaced upstream and downstream points of application for the binding organ to get tensioned in both an upstream and downstream direction towards neighboring safety devices during a rotation in the loosening direction thereof.
2. A safety assembly according to claim 1, wherein the binding organ is a rubber band.
3. A safety assembly according to one of the preceding claims, in which each position indicating means comprises a nose part which projects radially outwardly from the body, and wherein each guiding path extends at least partly along this nose part.
4. A safety assembly according to claim 3, wherein the upstream and downstream application points are positioned at opposing sides of the nose part.
5. A safety assembly according to claim 3, wherein one of the upstream and downstream application points is positioned at the nose part, whereas the other one is positioned interspaced therefrom alongside the body
6. A safety assembly according to claim 5, wherein the nose pad comprises a hook for the binding organ to get hooked behind.
7. A safety assembly according to one of the preceding claims, wherein each guiding path is at least partly formed as a gutter for the binding organ to run through.
8. A safety assembly according to one of the preceding claims, in which each body comprises a hood at its upper side for capping the first and/or second mounting member, wherein the guiding path at least partly runs around the hood.
9. A safety assembly according to claims 7 and 8, wherein the gutter is formed around the hood.
10. A safety assembly according to one of the preceding claims, wherein each guiding path is at least partly open towards an upper or lower side of the body such that the binding organ can freely be placed therein from above or underneath.
11. A safety assembly according to one of the preceding claims, wherein the guiding path extends at one side of the central axis such that the binding organ merely runs at this one side of the central axis.
12. A safety assembly according to one of the preceding claims, wherein each bore is provided with a profile, in particular a set of axially extending interspaced grooves, to fit with a form fit over the second mounting member.
13. A safety assembly according to one of the preceding claims, wherein the binding organ extends as a closed loop along and between the plurality of safety devices.
14. A safety device for use in a safety assembly according to one of the preceding claims, wherein each safety device is provided with a guiding path for a binding organ to extend along, wherein the guiding path forms upstream and downstream points of application for the binding organ to get tensioned in an upstream and downstream direction towards neighboring safety devices during a rotation in a loosening direction thereof.15-Method for using a safety assembly according to one of the preceding claims, comprising the steps of: -filling the plurality of safety devices with their bores onto the second mounting members, with the position indicating means indicating rotational positions thereof; -having the flexible elongate binding organ extend along and between the guiding paths of the safety devices, with the binding organ lying against the upstream and downstream points of application; -counteracting the second mounting members to rotate in their loosening direction by having the binding organ get tensioned in both the upstream and downstream direction during such a rotation in the loosening direction.