FR2508625A1 - Test rig for damaged vehicle geometry check - has square mesh spaced drillings for attachment of measuring devices - Google Patents

Abstract

The rigid monobloc rectangular horizontal frame (1) carries strengthening cross-beams, angle brackets (2), thickness wedges (3), magnetic screw plates (4), end pivots (5) and a measuring device (6). The latter consists of a weighted extensible graduated tape depending from a hook on to a square mesh projection plate which is secured at two or more of the spaced fixing holes. The frame can be rotated on the end pivots to bring either upper or lower main surface into use. It can be floor-mounted, wheeled, or secured at either end to a lifting gantry.

Description

 The present invention relates to a simple dimensional control device for bodies, chassis or mechanical parts of motor vehicles, used jointly and complementarily to the improved universal bench, object of French Patent Application no. 79.07506, filed on 03/26/1979.

 When a vehicle has suffered damage which affects, or is likely to affect, its bodywork or its chassis, L j, articulately its fundamental geometry, that is to say the essential points, the integrity of which governs the behavior and vehicle safety (generally the points of assembly of the mechanical parts on the body or the chassis, or reference points voluntarily arranged by the manufacturer at determined locations) its repair is usually carried out using a bench (formerly called "marble") which serves as a support, and often as a reference base for a dimensioning control device using - either the method called "Positive Control", by which a set of fittings, specific to the vehicle model considered my spatializes the shape and position of the essential control points which constitute the original geometry of the vehicle.

- or to the so-called "Measurement" method, by which the dimensions recorded on the vehicle are compared by means of various processes (mechanical, optical, electro-optical, etc.), with the dimensions "of origin" "corresponding, which generally appear on an odds sheet, specific to the vehicle model considered.

 In the prior art, the various devices and devices using the so-called "Measurement" method - not only only exceptionally made it possible to follow the progress of the fitness work by accompanying the straightening movement printed with the deformed elements - no only were of bulky dimensions requiring careful precautions during their use as for their storage, and prohibiting for example their easy transport by the Expert wishing to check the conformity of the work carried out and its results, - but their design, putting in play delicate devices, materialized by a great complexity, having as a consequence an overall fragility not well adapted to the usual working conditions in repair shops bodywork the need to reserve their use to highly qualified and particularly conscientious staff a high cost restricting their distribution, and contributing to the worsening - unanimously deplored - of the cost of repairing car accidents.

So it would be extremely advantageous to have a device which is distinguished by - w great simplicity
of design and implementation, leading
- robustness compatible with conditions - sometimes
fairly rough - used in a repair shop
bodywork1 quite distant in practice from those of Rencon
very metrolDgie laboratory.

- at a sufficiently low price to ensure a wide range
dissemination, especially to small businesses,
craft in particular.

of use
it puts it within the reach of qualified staff.
tion ran in the professinn, on the one hand
- by allowing significant savings in operating time, and by
substantial savings, on the other hand.

- the fact of being easily portable, in order to be able to be used without difficulty at various points of the same vehicle, on several vehicles of the same workshop, or even transported easily and without risk in different establishments, even distant some others.

Consequently, the object of the present invention is precisely, by taking advantage of the decimetric modular drilling plan of the ulva at least of the 2 main faces of the universal bench which is the subject of the Patent Application mentioned above1, a device capable of reconciling these various requirements, and to remedy the "aforementioned drawbacks.

The main object of the invention is to be able to easily and precisely check the position of a point in space by measuring its coordinates in 3 dimensions.

This goal is achieved by determining - the coordinates of the projection of the point considered, on a
horizontal reference plane (length, width), on the one hand - the vertical distance from the point considered to the project plane @
(height) on the other hand
And in particular: - using the horizontal face as the horizontal reference plane
of the universal bench already mentioned, and its modular drilling
which constitutes a grid with mailLe square of 100 mm of side.

- by making an expandable rod capable
materialize the vertical projection of the point to be checked1
on the horizontal reference plane.

to give zen, by direct reading, the height of the point to control
relative to the horizontal reference plane.

This is the reason why object of the invention is an original device made up of three main elements - at least one projection plate, which aims to subdivide
the decimetric grid of the bench materializing the hori plane
projection zontal.

- in the hand a weighted stretch rod, which aims to materialize
read the vertical projection of the point to control, using
the combined properties of plumb line and measuring tape - one or more rod suspension devices, suitable for
the vehicle to be checked.

 The extensible rod consists essentially of a gra rubée and a hollow mass receiving at rest the graduated ribbon and its balancing spring, and terminated by a ballast point.

 In order to facilitate the use of the device, the hollow mass may allow the adjustment of the balancing spring and the blocking of the graduated tape.

 Mobile IDEs also offer greater ease of reading on the projection plate and on the vertical graduated tape.

 A system of adjustable clamps finally allows the extendable rod to be suspended in conditions suitable for ensuring the accuracy of the measurements, despite the great diversity usually presented by the elements to be checked on vehicles: tr @> 1 bolt heads, etc.

 The main characteristics of the various elements constituting this original device will be described with reference to the accompanying drawings by way of example, and in which - FIG. 1 is a perspective view of the assembly of the device according to the invention - FIG. 2 is a section of the lower ma @@ e of the extendable rod, showing in particular its interior arrangement - FIG. 3 is a partial section showing the outlet channel of the graduated tape - FIGS. 4 and 5 are sections illustrating the principle of operation of the adjustable clamps which allow the attachment of the extendable rod to the partias to be controlled of the vehicle.

 A first important object of the invention is to materialize the horizontal projection plane with a more precise dimensional subdivision than that constituted by the modular drilling of the capahle bench, in particular to provide a reading precision greater than the dimensional tolerances commonly accepted in matters of automobile bodywork. .

 The plate or plates called "projection" (Figure 1, item 1) therefore have, on their upper side, a millimeter quad-illuated graduation (or any other graduation offering a reading accuracy of the same order, to be used for example in countries where the metric system is not in use) so that the position, in length and width, of the projection of the points to be checked can be directly detected.

 These projection plates have a small and constant thickness, and external dimensions such that they allow the exact juxtaposition of several of these plates, for example in the case where it is desired to have a more reading surface. extended, to quickly and simultaneously control several points of the vehicle.

 The adaptation feet, located under the underside of the plate, are arranged according to the decimetric module corresponding to the three of the bench, and are accommodated without appreciable play in said holes, thus ensuring the precise positioning of the plate relative to the bench .

 A second important object of the invention consists in materializing the vertical projection of the point to be checked.

 This is why the extensible rod preferably comprises a ribbon, made of a flexible but inextensible material (Figure 1, item 2), the upper end of which receives a sufficiently low friction connection to ensure the exact verticality of the assembly of freelance. By way of nonlimiting example, this link can be easily constituted by a few suitably sized net chain links, as illustrated in FIG. 1, item 3.

 This is also why this same stretching rod has, at the bottom of the ribbon1 a mass (Figure 1, item 4 and Figure 2, items 2 to 10) of generally cylindrical-conical shape evoking the universally known silhouette of the classic plumb line, and of which the lower part, preferably metallic (Figure 2, item 2) serves as ballast for all of the extendable rod. This lower part ends with an axial point having an angle sufficiently acute to locate with precision, on the aforementioned gridded plate (Figure 1 mark 1) the projection of the point to control.

 A third important object of the invention resides in the measurement of the vertical distance (or height) of the point to be checked relative to the reference plane.

 Also the tape of the extendable rod has a millimeter graduation (or any other gradation providing a reading accuracy of the same order).

 The main body (Figure 21 item 3) of the hollow mass consists of several assembled elements, which can be produced, for example in no way limiting, in molded plastic, joined by screws, or using an elastic ring open such as that shown in Figure 2, item 4, and designed so that said main body can receive, not only, at its lower part, the ballast point (Figure 2, item 2) described above, but also - at rest, the graduated tape (Figure 2, item 1) wound at the center of the classic tape measure, but in such a way that the center of gravity of the mass does not vary laterally1 regardless of the length of tape stored in the body main. This result is obtained by ensuring the vertical exit of the ribbon in the mass ase.

a balancing device for the assembly, in the form, for example, of a sp --- l spring (FIG. 2, item 5) of the current type, the tension of said spring possibly being adjustable by means of, example, a threaded axis (Figure 2, item 6) terminated by a slot in which the end of said spring would engage. The rotation of said axis, in one direction or the other, would then have the effect of increasing or decreasing the tension of the balancing spring, so that the ma '; does not spontaneously tend or rise, nor to go down.

- at its upper part, the channel $ (Figures 2 and 3, item 7) for the output of the graduated ribbon 1 the line of the said catral having a curvature capable of ensuring the exit of the ribbon in the axis of the mass, ric so as to preserve to said mass ulule perfect verticality.

Said outlet calas carries at its end a fixed wrinkle (Figure 2, item 8) intended to pinpoint the length of the ribbon served. This index could for example, come directly molding with the corresponding part of the main body of the mass.

In order to facilitate the use of the extendable rod, in particular during the straightening operation of the bodywork, the ribbon can be locked in position using a simple device constituted, for example without limitation, by a push button ( Figure 2, item 9) whose lateral movement has the effect of wedging the ribbon between the wall of its outlet channel and a swollen portion of said pusher (Figure 3, item 10).

 The appreciation of any differences between the dimensions sought - that is to say those of origin, expressed by the dimension sheets established for each type of vehicle according to the dimensional characteristics published by the manufacturer - and those actually noted on the vehicle to be checked, can also be advantageously facilitated by the identification of the values sought, by means of removable indexes of suitable shape and color, displaying said original values - on the one hand, on the projection plate (length and width) by any appropriate means (adhesion, magnetic attraction or any other means).

- on the other hand, on the graduated tape of the extendable rod (height) by any appropriate means (pinching, adhesion, magnetic attraction or any other means).

 The repair actions to be undertaken (straightening for example) are thus determined immediately and precisely, in direction and in value.

The attachment of the upper end of the extendable rod to the points to be checked of the vehicle is made difficult - by the fact that the check must be able to be carried out, than the mechanical elements of the vehicle (front and rear axles, powertrain , etc ...) are in place or not ("naked" body), on the one hand - due to the extreme diversity of nature, shape and dimensions that affect, in practice, the elements that materialize the points to be checked, on the other hand
These last elements most often affect the form
holes, smooth or more rarely tapped
bolt heads, or whose dimensions vary significantly from one to the other.

It is therefore advisable to make a device - adaptable to these different cases - space-saving - simple and quick to implement - suitable for ensuring the suspension of the extendible rod in 17 immediate v-isle of the control point defined by the cons vehicle tracer.

This is the object of the device shown, in its two versions, in Figures 4 and 5 respectively. Said figures were established - in section, in order to illustrate the - operating principle - in the extreme dimensional conditions of their use
Figure 4: holes with the smallest common diameters (part
lower of the figure) and the stronger (upper part)
Figure 5. hexagonal nuts of common widths on flats,
the weakest (bottom part of the figure) and the most
strong (upper part).

In both versions, a screw (Figures 4 and 5, item 2) with knurled head to facilitate maneuvering by hand, controls the opening or closing of claws (item 3) articulated in a nut (reference 4) itself knurled, and provided, on one of its faces, with a central recess, and with radial slots receiving the claws and allowing their controlled debateternent - either directly by the end of the knurled screw figure 4, item 2), for hanging in a hole, by spreading the claws - either by means of a support nut (Figure 5, item b) for hanging on a bolt head or on a @crou, by bringing the claws together.

An open ring (item 1i r pivots the head of the knurled screw (item 2) 1 where it is retained, for example, limiting black, by means of a circular groove (item 5) and a staple (or a ela @ lique annular clip) in order to ensure the extended freelance
Possible a perfectly vertical suspension.

In the cases, much rarer, where the point to be checked would appear in a form different from those envisaged above, the open orientable ring would be coupled to a permanent nimant of suitable shape.

 The measuring device 1 which is the subject of the invention can be used for the dimensional control of bodies, chases or mechanical parts of motor vehicles, particularly after collision riori only by body repairers before (diagnosis), during (monitoring of straightening , implementation of restructuring) and after repair operations (control), but also, thanks in particular to its very small footprint which makes it easily portable, by Experts during their damage assessment missions and advice on the choice of operating thes.

 In addition, the very principle of measuring the coordinates of the points to be checked, lends itself very directly to the use of the original device described above for teaching actions, in particular because of its immediate relationship with both the classical principles of descriptive or dimensioned geometry, of which it constitutes the concrete application, only with the procedures for the rating of the bodies used for the ". drawings drawn up by vehicle manufacturers.

 Finally, at the stage of the manufacture of bodywork, this same device allows rapid checks, e assembly line or off-chain, in excellent conditions of reliability and speed.

Claims (9)

 1. Device intended for the vertical measurement of the height of a point to be checked above a horizontal projection plane, characterized in that it comprises an extendable rod constituted by - on the one hand, a millimeter graduation ( or offering a  read accuracy of the same order) carried directly on  a vertical ribbon terminated at its upper end by  a low friction connection, - on the other hand, a terminal mass, of substantially shaped  cylindrical-conical with vertical axis, and comprising  a hollowed-out main body terminated by a lower point  forming ballast; the main body receiving the winding at rest  spiral of the aforementioned graduated ribbon and its balancing spring  and comprising, at its upper part, an outlet channel of which  the layout ensures the exit of the graduated ribbon in the axis of said  mass, and an index allowing the reading of the length of  ribbon in use.  2. Device according to claim 1, characterized in that the main body of the extendible rod comprises a device for adjusting the tension of the balancing spring, constituted by a threaded element terminated by a slot receiving the end of the spring, and the rotation of which, in one direction or the other, has the effect of increasing or decreasing the tension of said spring.  3. Device according to one of claims 1 and 2, characterized in that the main body of the extendable rod comprises a device for blocking the graduated tape, which blocking device consists, at the upper part of said main body, of a pusher boss whose operation has the effect of wedging the graduated tape against the wall of its outlet channel.  4. Device according to one of claims 1 to 3, characterized in that at least one movable index, fixed on the graduated tape of the extendable rod, displays, on said graduated tape, the desired height of the contrd point  5. Device according to one of claims 1 to 4, characterized in that it comprises means for hooking the rod on an object, such as a car body, including the point or points to controller.  6. Device according to claim 5, characterized in that the hooking means comprise claws adjustable symmetrically about an axis, which allows them to be hooked in holes of variable diameter, or on nuts or heads of bolts of variable diameter.  7. Device according to one of claims 1 to 6, characterized in that it comprises a grid plate fixed on a support defining said horizontal projection plane, the lower point of the rod allowing a determination of position in the plane of said grid .  8. Device according to claim 7, characterized in that the support comprises a modular bore allowing the establishment of the grid plate in different predetermined positions relative to each other.  9. Device according to one of claims 7 and 8, characterized in that the support is included in a dimensional test bench of vehicles.