APPARATUS AND METHOD FOR MEASURING WHEEL POSITION ON A MOTOR VEHICLE

Abstract

A measuring apparatus comprising a base (4), the base comprising two spirit levels (81, 82), an upright (3) fixed rigidly to the base, a first sliding support (1) mounted on the upright and sliding along the upright, with a locking device for immobilizing the first sliding support relative to the upright, a second sliding support (2) mounted on the upright and sliding along the upright, with a locking device for immobilizing the second sliding support relative to the upright, the first sliding support comprising a contact finger (11) for contacting an external wing or mudguard element of a vehicle, and the second sliding support supporting a laser rangefinder (6) for measuring the distance between a reference point of the rangefinder and the tire, and a corresponding measuring method. Figure in the abstract: Fig. 4

Description

Title of the invention: APPARATUS AND METHOD FOR MEASURING A WHEEL POSITION ON A MOTOR VEHICLE

[0001] The invention applies to the general field of apparatus and methods for measuring the position of a wheel of a motor vehicle relative to a reference element of the body of said motor vehicle.

[0002] This type of measuring device is used to verify the conformity of a vehicle during its manufacture in a vehicle assembly plant. Naturally, the device in question can be used to measure the position of each of the four wheels of the motor vehicle in question. Each wheel is fitted with a tire.

[0003] More specifically, the device in question makes it possible to measure the position of the tire according to the transverse direction of the vehicle and according to the vertical direction, in relation to a wing or mudguard element which directly overhangs the tire.

[0004] A device for this type of need has already been proposed as described in document FR3086747. However, the device proposed in this document presents a significant complexity with two orthogonal laser beams and a change of position during the process in order to obtain a relevant measurement.

[0005] The inventors therefore sought to design an apparatus and an associated method which forms a simple and quick solution to implement, which does not require staff training, and which is usable for a variety of vehicle types which need to be treated.

[0006] In this regard, the invention proposes a measuring device comprising a base, with height-adjustable feet (for example, of the screw / nut type), the base comprising two spirit levels, an upright fixed rigidly to the base (without any degree of freedom), a first sliding support, mounted on the upright with a single degree of freedom, namely sliding along the upright, with a locking device capable of immobilizing the first sliding support relative to the upright, a second sliding support, mounted on the upright with a single degree of freedom, namely sliding along the upright, with a locking device capable of immobilizing the second sliding support relative to the upright, characterized in that the first sliding support comprises a contact finger intended to come into contact with an external element of a wing or mudguard of a vehicle,and in that the second sliding support supports a laser rangefinder intended to measure the distance between a reference point on the rangefinder and the tire.

[0007] Thanks to these arrangements, the device in question is simple and easy to implement. The height of the first and second sliding supports is adjusted, then the base is brought close until the contact finger touches the outer element of a wing or mudguard of a vehicle, the horizontality of the base is checked or corrected if necessary, and then the measurement is triggered by the laser rangefinder.

[0008] The measurement obtained gives, after subtracting a predetermined calibration value, the transverse position deviation of the tire relative to the wing of the vehicle.

[0009] Advantageously, the device is simple and robust. It can be used to process a wide variety of different vehicles without tedious adjustments.

[0010] It should be noted that the laser rangefinder is securely attached to the second sliding support.

[0011] Spirit levels allow the horizontality of the base to be checked or corrected.

[0012] According to an advantageous option, the base is mounted on a wheeled trolley.

[0013] The device is therefore easy to move. It can be rolled from one wheel to another. The device is also easy to store.

[0014] According to one embodiment, at least one roller is equipped with a brake. This allows the measuring device to be immobilized in a given position, for example during the measurement operation.

[0015] According to an alternative embodiment, one or two handles are provided for lifting the device. In this case, the base is placed directly on the floor.

[0016] According to one embodiment, the contact finger has a free end that is convex and / or has a smooth and soft surface.

[0017] According to a practical example, the contact finger can be equipped at its end with an elastomer pad or a Teflon pad.

[0018] This avoids any damage that could be caused by contact on the wing of the vehicle, in particular to the paintwork.

[0019] According to one embodiment, the device may further include a sliding square fixed to the first sliding support, the square having graduated arms for measuring the free interval separating the top of the tire from the underside of the wheel arch. This is a simple, robust, and reliable system for measuring the distance between the top of the tire and the top of the wheel arch.

[0020] According to one embodiment, the locking device is formed as a screw-nut clamping device. Such a clamping system allows the sliding support to be adjusted to any vertical position; there is no notching effect.

[0021] According to an alternative embodiment, the locking device may be based on a system of notches, each of the larger ones being separated by a distance of a few millimeters. For example, there may be a latch rod that inserts into the notches under the effect of a spring returning against a manual action performed by an operator.

[0022] According to one embodiment, the upright includes a longitudinal slot adapted to receive at least one rod connected to the first sliding support and / or second sliding support. The longitudinal slot receiving said rod provides guidance and limits the stroke of the sliding supports.

[0023] According to one embodiment, the upright includes a spirit level. This allows for a double check of the device's posture, verifying that the upright is correctly vertical.

[0024] The present invention also relates to a method of measuring the position of a wheel of a motor vehicle using a measuring device as described above, the motor vehicle comprising a wheel and a wheel arch, - position the base near the wheel, - adjust the height of the first and second sliding supports - adjust the base horizontally, - bring the contact finger into contact with the wheel arch, by moving the base - trigger the measurement by the laser rangefinder, - subtract a calibration value from the measurement obtained to obtain a net value, - compare the net value with a prescribed interval to determine the conformity of the motor vehicle.

[0025] According to one embodiment, the method may provide that the height of the first sliding support is adjusted so that the contact finger is at the height of the most prominent part of the wing or mudguard, and the height of the second sliding support is adjusted so that the laser beam of the laser rangefinder is at the height of the curved sidewall of the tire.

[0026] According to one embodiment, the method may provide that a free interval separating vertically the top of the tire from the bottom of the wheel arch is also measured using a sliding square. In practice, you open the set square and take a direct reading on the graduated ruler. It's a simple, rustic, and reliable solution.

[0027] The invention will be further detailed by describing non-limiting embodiments, and based on the accompanying figures illustrating variants of the invention, in which: [Fig.l] schematically illustrates, in elevation view, an example of a measuring device according to the present invention, in a situation of implementation for measuring the position of a vehicle wheel; [Fig.2] is analogous to [Fig.1] and shows another example of a measuring device equipped with a wheeled trolley under the base; [Fig.3] illustrates in elevation view another example of a measuring device; [Fig.4] illustrates in perspective view the measuring device of the [Fig.3]; [Fig.5] shows a diagram illustrating the measurement logic along the transverse direction.

[0028] In the different figures, the same references designate identical or similar elements.

[0029] Device

[0030] Figures 1 and 2 illustrate a measuring device 10 in use for the purpose of verifying the conformity of a vehicle during its manufacture in a vehicle assembly plant.

[0031] The vehicle in question may be a passenger vehicle, a utility vehicle, a van, a recreational vehicle, a minibus, a coach, a truck, etc.

[0032] The vehicle in question comprises at least four wheels, only one wheel 9 being shown in profile in the figures. Each wheel 9 is fitted with a tire 19.

[0033] We are interested here in the lateral profile of the vehicle and in particular in zone 8 which directly overhangs the wheel. This zone generally forms the overall transverse dimension at the level of the wheel region. The wheel 9 and the tire 19 are generally located slightly recessed towards the inside. Of course, the present invention is not limited to this case.

[0034] The area marked 8 represents the outermost wing element (or mudguard of a vehicle), which is located furthest out and which forms the overall width dimension.

[0035] The vehicle may or may not include a mudguard. In the absence of a mudguard, the wing directly forms the external element of interest.

[0036] The measuring device 10 proposed herein comprises a base 4. The base is a solid, rectangular metal plate. With reference to [Fig. 4], the solid plate forming the base 4 extends along two orthogonal directions V and W perpendicular to the vertical direction Z.

[0037] The base 4 has a length L1 of 25 cm to 50 cm, a width L2 of 25 cm to 40 cm, a thickness of 8 mm to 20 mm, without these values ​​being limiting.

[0038] It is preferable to use a base that weighs at least 3 or 4 kilograms to ensure good stability. However, it should be noted that it is possible for the base to be made of a different material and could be lighter.

[0039] In order to ensure horizontal adjustment of the base if the device is installed on a floor that is not perfectly horizontal, the base includes adjustable feet, to allow height adjustment of each one.

[0040] In the illustrated example, the base 4 is equipped with three height-adjustable feet marked respectively 91, 92, 93.

[0041] In practice, a foot includes an external thread, and is received in a threaded bore provided in one of the corners of the base, for fine height adjustment according to the rotation given to the foot.

[0042] Furthermore, the base is equipped with two spirit levels, a spirit level 81 for adjustment along the direction V and another 82 for adjustment along the direction W.

[0043] The measuring device 10 proposed here includes an amount 3.

[0044] In the illustrated example, the upright is a tubular profile with a general square cross-section. The upright is welded to the base in a position perpendicular to the plane of the base, i.e., along the Z-axis direction.

[0045] Amount 3 is fixed jointly to the base.

[0046] The height of the upright marked H0 can be between 75 cm and 100 cm.

[0047] The upright 3 includes a longitudinal slot 31, through which extends along the axis Z3, from a lower end 31a to an upper end 31b.

[0048] The longitudinal slot 31 is provided to receive a rod linked to the first sliding support and / or second sliding support.

[0049] Amount 3 may include a spirit level, not shown in the figures.

[0050] The measuring device 10 proposed here includes a first sliding support 1. The first sliding support is mounted on the upright 3 with a single degree of freedom along Z3, namely sliding along the upright 3.

[0051] A locking device is provided to immobilize the first sliding support relative to the upright. The locking device is described below.

[0052] The first sliding support 1 has a contact finger 11 intended to come into contact with the outer wing or mudguard element 8 discussed above.

[0053] The contact finger 11 has a free end that is convex and / or has a smooth, soft surface. For example, the contact finger may be fitted at its end with an elastomer pad or a Teflon pad.

[0054] In addition, the measuring device 10 includes a second sliding support 2. The second sliding support 2 is mounted on the upright with a single degree of freedom along Z3, namely sliding along the upright 3.

[0055] Another locking device is provided suitable for immobilizing the second sliding support 2 relative to the upright 3.

[0056] The second sliding support 2 supports a laser rangefinder 6 used to measure the distance between a reference point of the rangefinder and the sidewall of the tire 19. As known ensoi, a laser beam 16 is emitted along an axis A6 towards a target and the resulting light echo interferes with the incident light to allow the distance traveled to be determined.

[0057] According to one option, the base 4 is mounted on a wheeled trolley marked 5. For example, casters of the freewheel type can be chosen to allow easy movement in all horizontal directions.

[0058] The trolley 5 is equipped with four wheels. At least one of the wheels, or even two wheels, is equipped with a brake.

[0059] The body of the trolley has a plate of similar dimensions to the dimensions of the base and can be made of wood or plastic.

[0060] As already mentioned above, each of the sliding supports is equipped with a locking device to fix its vertical position.

[0061] The locking device is formed as a screw-nut clamping device. Such a clamping system allows the sliding support to be adjusted to any vertical position. In the illustrated example, the two locking devices are similar, but they could be different.

[0062] In practice, the clamping device includes a bolt whose head 35 is pressed on one side against the sliding support to be blocked, with the threaded end of the bolt cooperating with a wing nut 36 which bears on the upright.

[0063] The main shank of the bolt passes through the longitudinal slot 31.

[0064] To lock the sliding support, tighten the wing nut, and conversely to unlock the position of the sliding support, simply loosen the wing nut.

[0065] Furthermore, according to a supplementary feature, the device may also include a sliding bracket 7.

[0066] The sliding bracket 7 is fixed to the first sliding support 1. The sliding bracket 7 includes a graduated sliding arm, moving along Z3.

[0067] The sliding square 7 is configured to measure a free interval H7 separating the top of the tire from the bottom of the wheel arch.

[0068] The sliding bracket 7 includes a right-angled arm 71, either fixed relative to the first sliding support 1 or movable vertically relative to the first sliding support 1.

[0069] Another arm 72, straight, is provided, used in conjunction with the first arm to present two parallel external edges, suitable for contacting two parts whose spacing is to be measured.

[0070] Process

[0071] For the use of the proposed measuring device, the following procedure is followed.

[0072] Position the base 4 near the wheel.

[0073] The height of the first sliding support 1 and the second support are adjusted sliding 2.

[0074] The base can be adjusted horizontally if necessary, using the adjustable feet.

[0075] The contact finger 11 is brought into contact, by moving the base, with the outer element of the wing or mudguard of a vehicle,

[0076] The measurement is triggered by the laser rangefinder 6. The measurement obtained is noted D2, which corresponds to the distance between the focal point of the rangefinder noted R2 and the point of contact on the tire noted 12.

[0077] A calibration value DI is subtracted from the measurement obtained to obtain a net value denoted DN. Let DN = D2 - Dl.

[0078] The calibration value Dl represents the distance between a reference point RI of the first sliding support and the point of contact on the outer wing element. The net value DN is compared to a prescribed interval to determine the conformity of the motor vehicle. This interval represents the acceptability of the measured vehicle.

[0079] This interval can be obtained from a calibration table which lists the acceptable intervals according to the type of vehicle, the type of tire fitting, and where applicable the tire pressure or even the vehicle load.

[0080] In practice, the height H1 of the first sliding support 1 is adjusted so that the contact finger 11 is at the height of the most prominent part of the wing or mudguard, and the height H2 of the second sliding support 2 is adjusted so that the laser beam of the laser rangefinder is at the height of the curved sidewall of the tire 19.

[0081] Optionally, the free interval H7 separating the top of the tire from the bottom of the wheel arch is also measured using the sliding bracket 7.

Claims

Demands

1. Measuring apparatus (10) comprising: - a base (4), with height-adjustable feet, the base comprising two spirit levels (81, 82), - an upright (3) fixed rigidly to the base, - a first sliding support (1), mounted on the upright with a single degree of freedom, namely sliding along the upright, with a locking device capable of immobilizing the first sliding support relative to the upright, - a second sliding support (2), mounted on the upright with a single degree of freedom, namely sliding along the upright, with a locking device capable of immobilizing the second sliding support relative to the upright, characterized in that the first sliding support comprises a contact finger (11) intended to come into contact with an external element of a wing or mudguard of a vehicle,and in that the second sliding support supports a laser rangefinder (6) intended to measure the distance between a reference point on the rangefinder and the tire.

2. Measuring device according to claim 1, characterized in that the base is mounted on a wheeled trolley (5).

3. Measuring device according to claim 2, characterized in that at least one wheel is equipped with a brake.

4. Measuring device according to any one of claims 1 to 3, characterized in that the contact finger (11) has a free end that is convex and / or has a smooth, soft surface.

5. Measuring apparatus according to any one of claims 1 to 4, further comprising a sliding square (7) fixed to the first sliding support (1), square with graduated arm for measuring a free interval separating the top of the tire from the bottom of the wheel arch.

6. A measuring device according to any one of claims 1 to 5, characterized in that the locking device is formed as a screw-nut clamping device (35,36).

7. A measuring device for any one of claims 1 to 6, characterized in that the mount comprises a longitudinal slot (31), capable of receiving at least one rod linked to the first sliding support and / or second sliding support.

8. Method of measuring a wheel position of a motor vehicle using a measuring device according to any one of claims 1 to 7, the motor vehicle comprising a wheel (9) and a wheel arch (8), - position the base (4) near the wheel, - adjust the height of the first and second sliding supports - adjust the base horizontally, - bring the contact finger (11) into contact with the wheel arch (8), by moving the base - trigger the measurement by the laser rangefinder (6), - subtract a calibration value (Dl) from the measurement obtained (D2) to obtain a net value (DN), - compare the net value with a prescribed interval to determine the conformity of the motor vehicle.

9. A measurement method according to claim 8, characterized in that the height (H1) of the first sliding support (1) is adjusted so that the contact finger (11) is at the height of the most prominent part of the wing or mudguard, and the height (H2) of the second sliding support (2) is adjusted so that the laser beam of the laser rangefinder is at the height of the curved sidewall of the tire (19).

10. A measurement method according to claim 8, characterized in that a free interval (H7) separating vertically the top of the tire from the bottom of the wheel arch (8) is also measured by means of a sliding square (7).