WHEEL NUT INDICATOR

Abstract

A wheel nut indicator 10 includes an attachment section 12 for fitting to a wheel nut/lug nut of a wheel and a pointer section 14 extending radially away from the attachment section 12, the wheel nut indicator 10 being provided with a changeable secondary indication means which is moveable between a first position (FIG. 1) for indicating a first status, and a second position (FIG. 3) for indicating a second status.

Description

FIELD OF INVENTION

The present invention relates to a wheel nut indicator, and particularly to a wheel nut indicator having a movable secondary indication means.

BACKGROUND TO THE INVENTION

Wheel nut indicators are well known, and are considered an important safety feature for large vehicles, for example buses and trucks. A wheel nut indicator is generally in the form of a plastic cap or surround, which fits over the wheel nuts/lug nuts on a vehicle wheel, and which has some kind of pointer. When the wheel nut indicators are installed over the nuts, the pointers will be oriented in a particular direction, for example, the pointers may all be oriented so that they point clockwise around the wheel, or alternatively the pointers of adjacent wheel nuts may point towards each other. The purpose of this is so that any rotation of a wheel nut (because it is becoming loose) will be immediately obvious on visual inspection, because the pointer of the wheel nut indicator will no longer be pointing in the correct direction. As a matter of routine, a driver will carry out a defect check on a vehicle before driving it, and will check the indicators on each wheel. Any problems with loose nuts will therefore be detected and corrected before they become dangerous.

When a wheel is removed for whatever reason (for example to replace the tyre or service the brakes), wheel nuts will be fitted and tightened, and wheel nut indicators will be fitted over the nuts. It is then standard practice to require checking and re-torqueing after the vehicle has been driven a short distance, for example 40-80 km. Generally a paper document is given to the driver, and it is the driver's responsibility to ensure that the vehicle is returned for re-torqueing after that distance. However, there could be times when this paper system is less effective than desired. For example, the document may be lost, a driver change may occur with the paperwork not being handed over, or the wheel might be removed and refitted when there is no driver to hand the paperwork over to. Likewise, repairs might have to be made to dismounted trailers in yards/docks etc.

All of these events could lead to a re-torqueing policy being inconsistently applied. Even if a driver remembers that re-torqueing is required, a situation may arise where he or she incorrectly identifies which wheel is affected, if the paperwork is misplaced or unreadable, for example because it is covered in dirt or grease.

It is an object of the invention to reduce or substantially obviate the above mentioned problems.

SUMMARY OF INVENTION

According to the present invention, there is provided a wheel nut indicator including an attachment section for fitting to a wheel nut/lug nut of a wheel and a pointer section extending radially away from the attachment section, the wheel nut indicator being provided with a moveable secondary indication means which is movable between a first position for indicating a first status, and a second position for indicating a second status.

The moveable secondary indication means allows the wheel nut indicator to indicate either of the first status or the second status. The status indicated may be changed, without removing or replacing the wheel nut indicator from the wheel nut/lug nut, by moving the secondary indication means of the wheel nut indicator. The secondary indication means may be movable with respect to the rest of the wheel nut indicator, in particular with respect to the attachment section.

The wheel nut indicator functions as an ordinary indicator, having a pointer for use as described above, so that any loosening of nuts can be detected visually. In addition, the secondary indication means can be used for recording a status of a nut, for example if the nut is newly fitted and therefore needs to be re-torqued after a short distance. When a wheel is removed and replaced, the wheel nut indicators can be fitted over the wheel nuts/lug nuts and the pointers aligned conventionally. The secondary indication means can be set in the first position to indicate that the nuts will need re-torqueing. Before driving his vehicle, a driver will check all wheels as is already standard practice. In addition to noting the position of the pointers on the wheel nut indicators, he will note the position of the secondary indication means. This serves as a reminder that the wheel has recently been changed and will therefore need re-torqueing, even if the driver has lost his paperwork or has taken over the vehicle from another driver.

When the wheel is checked and re-torqued, the secondary indication means on each wheel nut indicator can be moved to the second position, to indicate that this operation has been completed. This can be done without removing the wheel nut indicators, and does not require the driver or service mechanic to carry a supply of wheel nut indicators.

Preferably, the secondary indication means displays a first colour in the first position and a second colour in the second position. Colour is generally a good way of communicating status information, allowing a quick visual check. For example, the first colour may be green, indicating “safe” and the second colour may be red, indicating that the nuts need to be checked and re-torqued.

The secondary indication means may move in any of a number of ways. For example, it may include a slider, a rotatable element, or any other moveable part.

It is particularly preferable to provide the secondary indication means as part of the pointer of the wheel nut indicator. Preferably, substantially the entire surface area of the pointer provides visible status information, since drivers are already used to checking the pointers on their wheel nut indicators. In one embodiment, one side of the pointer displays a first status (for example the surface on that side may be a first colour) and the other side of the pointer displays the second status (for example the surface may be a second colour). The pointer is rotated so that the first side is facing away from the wheel in the first position and the second side is facing away from the wheel in the second position. This rotation may be about an axis which extends radially away from the attachment section.

Preferably, holding means are provided for holding the secondary indication means in the set position. It is important to ensure that the secondary indication means cannot move between positions due to vibrations when the vehicle is being driven.

In one embodiment, the pointer is provided with a substantially cylindrical hole extending through the centre of the pointer, in a radial direction away from the attachment section. The attachment section may be provided with a radially extending pin so that the cylindrical hole of the pointer may fit over the pin, and the whole pointer may rotate about the pin. The pointer may then be rotated so that either its first face or its second face faces away from the wheel in use.

The holding means may be in the form of one or more extensions from an edge of the pointer, the extensions fitting within apertures in a wall of the attachment section, the edge of the pointer being placed against the wall of the attachment section in use and the extensions therefore fitting within the apertures and preventing rotation. To rotate the pointer with respect to the attachment section to move the secondary indication means to a different position, the pointer must be pulled away from the attachment section so that the extensions on the pointer clear the apertures on the attachment section, then rotated, and then pushed back towards the attachment section so that the extensions fit back within the apertures, and the secondary indication means is locked in its new position.

Preferably, a spring is provided for urging the pointer towards the attachment section. In this way, force has to be applied against the spring to move the extensions clear of the apertures and rotate the pointer. When the pointer is in its new position, the extensions will tend to snap into the apertures to lock the secondary indication means in position automatically.

It will be clear that the extensions might alternatively be provided on the attachment means, with the pointer being provided with corresponding apertures.

Preferably the attachment means is in the form of a cap which has an open end for fitting substantially over a wheel nut/lug nut of a wheel. The pointer may be provided substantially adjacent the open end of the cap, or alternatively substantially adjacent the other (closed) end.

DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, and to show more clearly how it may be carried into effect, preferred embodiments will now be described by way of example only, with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a wheel nut indicator according to the invention, with the secondary indication means in the first position;

FIG. 2 is a perspective view of the wheel nut indicator of FIG. 1, while the secondary indication means is being moved to the second position;

FIG. 3 is a perspective view of the wheel nut indicator of FIG. 1, with the secondary indication means in the second position;

FIG. 4 is an exploded view of the wheel nut indicator of FIG. 1; and

FIG. 5 is a perspective view of a second embodiment of a wheel nut indicator according to the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring firstly to FIG. 1, a wheel nut indicator is indicated generally at 10. The wheel nut indicator 10 includes an attachment section 12 for fitting over a wheel nut/lug nut of a wheel, and a pointer section 14. The attachment section 12 is substantially in the form of a cap, having an open end 12a and a closed end 12b. In use, the cap can be fitted over a wheel nut/lug nut to substantially cover the nut. The attachment section has an interior profile which can fit over a hexagonal wheel nut/lug nut in any of a number of orientations. For example, the attachment section may be able to fit over the nut in 24 different orientations, or any other multiple of 6 (for hexagonal nuts). Short substantially cylindrical end sections 18a, 18b are provided at each end.

The attachment section 12 is made from a resilient material, for example plastics. The interior of the attachment section 12 is typically slightly less wide than a typical wheel nut/lug nut, so that the attachment section 12 deforms slightly when placed over a wheel nut/lug nut. This ensures a tight fit and reduces the possibility that the indicator 10 will become detached from the nut while the vehicle is being driven.

The pointer section is substantially arrow-shaped, having an edge 16c which conforms with the curved surface of the cylindrical end section 18b of the attachment section 12, and two straight edges 16a, 16b which meet to form a point 20, at a distal end of the pointer section 14 from the attachment section 12.

The pointer section includes a cylindrical aperture 22 running through the centre of the pointer section 14, from the centre of the curved edge 16c to the point 20, between the two straight edges 16a, 16b.

Referring to FIGS. 1 to 3, it is clear how the pointer section 14 may be rotated with respect to the attachment section 12. The cylindrical aperture 22 of the pointer section 14 fits over and around a radially extending pin 24, which protrudes from the attachment section 12. Extensions 26a, 26b are provided on the curved edge 16c of the pointer 14, and correspond with apertures 28 on the curved outer surface of the short cylindrical end section 18b. The pointer section 14 can be pulled in the direction of arrow A to move the extensions 26a, 26b clear of the apertures 28, and the pointer section 14 can then be rotated about the pin 24, as shown in FIG. 2. The pointer section 14 is shown in FIG. 3, with the other side facing away from the wheel in use (substantially upwards in the Figures). Since the two sides of the pointer section 14 are different colours, and also one side may include indicia 30 to indicate that the nuts need re-torqueing, the rotatable pointer 14 as described works as a secondary indication means.

Referring now in particular to FIG. 4, a spring 32 is provided for urging the pointer 14 radially towards the attachment means 12. In other words, the spring 32 urges the pointer 14 in a direction opposite to arrow A. The spring sits against a detent (not seen in the drawings) at the curved edge end of the cylindrical aperture 22 of the pointer 14. The spring is held at the other end by a washer 34 and a snap ring 36, in a recess 38 towards a distal end of the pin 24.

In FIG. 5, a second embodiment of a wheel nut indicator 10′ is illustrated. This embodiment is substantially identical to the first embodiment 10, save that the pointer 14′ is provided adjacent the lower short cylindrical end section 18a′, i.e. next to the open end 12a′ of the attachment section 12. The pointer will therefore sit substantially against the surface of a wheel, when fitted.

The wheel nut indicators 10, 10′ provide all the normal features of a wheel nut indicator, in that they provide a ready visual indication if a nut has rotated in use. In addition, the pointer 14 of the wheel nut indicator may be rotated when a wheel is removed and replaced, as a reminder that the nuts will shortly require re-torqueing. This provides a valuable extra safety feature, and takes advantage of the fact that drivers already inspect their wheel nut indicators as a matter of course.

The embodiments described above are provided by way of example only, and various changes and modifications will be apparent to persons skilled in the art without departing from the scope of the present invention as defined by the appended claims.

Claims

1. A wheel nut indicator including an attachment section for fitting to a wheel nut/lug nut of a wheel and a pointer section extending radially away from the attachment section, the wheel nut indicator being provided with a moveable secondary indicator which is moveable relative to the attachment section between a first position for indicating a first status, and a second position for indicating a second status.

2. A wheel nut indicator as claimed in claim 1, in which first indicia is displayed in the first position and second indicia is displayed in the second position.

3. A wheel nut indicator as claimed in claim 2, in which the first indicia is a first colour and the second indicia is a second colour.

4. A wheel nut indicator as claimed in claim 1, in which the movable secondary indicator includes a rotatable element.

5. A wheel nut indicator as claimed in claim 1, in which the movable secondary indicator is the pointer.

6. A wheel nut indicator as claimed in claim 4, in which the rotatable element rotates on an axis which extends substantially away from the attachment section.

7. A wheel nut indicator as claimed in claim 6, in which the axis extends away from the attachment section in a radial direction.

8. A wheel nut indicator as claimed in claim 1, in which holding means are provided for holding the secondary indicator in position.

9. A wheel nut indicator as claimed in claim 8, in which one or more extensions are provided on an edge of one of the movable secondary indicator and the attachment section, and in which corresponding aperture(s) are provided on the other of the movable secondary indicator and the attachment section, the extensions cooperating with the apertures to prevent rotation.

10. A wheel nut indicator as claimed in claim 8, in which the holding means are urged into a held configuration by a spring.

11. A wheel nut indicator as claimed in claim 1, in which the attachment section is in the form of a cap for fitting substantially over a wheel nut/lug nut of a wheel, the cap having an open end and a closed end.

12. A wheel nut indicator as claimed in claim 11, in which the pointer and the secondary indicator are provided adjacent the closed end of the cap.

13. A wheel nut indicator as claimed in claim 11, in which the pointer and the secondary indicator are provided adjacent the open end of the cap.

14. (canceled)