TITLE

Attachment system for a model structure and a method for adjusting and mounting a model structure

TECHNICAL FIELD

The present invention relates to an attaching system for a model structure in association with a supporting structure, comprising at least one bottom element mounted on the supporting structure.

BACKGROUND ART

When designing new models and prototypes for, among other things, motor vehicles, it is of great interest to be able to model a body in association with a prototype chassis constructed of a structure of beams. The model body, that is usually constructed of a plurality of separate parts, is attached to the chassis in such a way that this supports the model body.

In order to carry out modelling, it is necessary for the parts that combine to form the model body, for example a bonnet, to be positioned correctly on the chassis. Locating lugs are used at present, in the form of surface-ground pieces of steel that are glued in suitable places on the beam structure of the chassis. Initially, the model body consists of a modelling material, upon which a number of corresponding supporting surfaces are milled. The positions of the supporting surfaces are very well defined. These are used as fixing points when the model body is held in a milling machine that mills the structure of the model body. By corresponding locating lugs on the chassis and supporting surfaces on the model body then being matched with each other, the body is placed in the intended position in relation to the chassis, with the supporting surfaces resting against corresponding receiving surfaces on the locating lugs.

The locating lugs are normally over-dimensioned, so that the receiving surfaces for the supporting surfaces can be milled down to the precise positions afterwards, whereby the position of the model body can be adjusted

more precisely. This is often necessary on account of various mechanical deviations, for example due to stresses in the beam structure of the chassis.

In order to make a fixing between corresponding locating lugs and supporting surfaces, holes are drilled through the locating lugs and the beams to which they are attached. These holes consist of clearance holes for bolts and also locating holes for locating pins. The locating pins are passed through the beams and the locating lugs and are inserted into corresponding locating holes in the material of the supporting surfaces. The bolts are inserted into clearance holes in the beams and locating lugs and are made fast in a thread that has been cut in the material of the supporting surface.

According to an earlier variant, the mechanical deviations are corrected by the space being filled with isocyanate adhesive.

Document EP 1527985 A1 describes how locating lugs are attached to body components for positioning them on the chassis.

There are many disadvantages associated with the locating lugs that are used at present. When they are glued on, this means that neither the locating lug nor the corresponding piece of material can be reused if required, and also means that it is necessary to use adhesives that are injurious to health and harmful to the environment. In addition, attachment by gluing means that subsequent adjustments are not possible. The locating lugs must also be adjusted individually by milling. In addition, a number of holes must be made in the framework of the chassis for attaching the locating lugs, which is not desirable as this involves destructive machining.

There is thus a need for a versatile design tool for a flexible attaching system for a model body in association with a chassis structure, comprising fixing devices for a correct, reusable, adjustable and safe attachment of body components to the chassis structure, that does not require destructive machining of the chassis structure.

DISCLOSURE OF THE INVENTION

The objective problem that is solved by the abovementioned invention consists of the design of a versatile design tool for a flexible attaching system for a model body in association with a chassis structure, comprising fixing devices for a correct, reusable, adjustable and safe fixing of body components to the chassis structure that does not require destructive machining of the chassis structure.

The said problem is solved by a device as described in the introduction. In addition, the device is characterized in that it comprises at least one moveable element that is arranged to be attached to supporting surfaces that are specially arranged on the model structure, and at least one adjustable element arranged between the bottom element and the moveable element, with the system comprising, in addition, at least one fixing element arranged to attach the moveable element to the bottom plate, so that, in the attached position, the bottom element and the moveable element are pressed essentially towards each other, with the said adjustable element being adjusted in a suitable way.

Preferred embodiments are described in the subordinate claims.

A plurality of advantages can be obtained by means of the present invention:

- both the model structure and the supporting structure can be reused;

- no complicated machining is required for adjusting;

- the adjusting can be carried out repeatedly;

- no substances are used that are injurious to health or harmful to the environment.

BRIEF DESCRIPTION OF DRAWINGS

The invention will now be described in greater detail with reference to the attached drawings, in which:

Figure 1 a shows a bottom plate of the device according to the invention;

Figure 1b shows a sectioned view along the line A-A in Figure 1a;

Figure 2 shows a moveable plate according to the invention;

Figure 3a shows how the plates according to the invention are joined together;

Figure 3b shows the fixing for a locking screw in a sectioned view;

Figure 4 shows a model body component;

Figure 5 shows a model body component attached to a moveable plate according to the invention; and

Figure 6 shows another embodiment for a bottom plate in the device according to the invention.

MODES FOR CARRYING OUT THE INVENTION

Figure 1a and Figure 1b show a chassis component in the form of an extruded aluminium profile 1 with two essentially parallel T-shaped slots 2, 3 made in an otherwise essentially flat surface. A bottom plate 4 rests on the aluminium profile 1 , which bottom plate is constructed with a first main surface 5 and a second main surface 6, which main surfaces 5, 6 are essentially parallel, with the second main surface 6 facing towards the aluminium profile 1. In addition, the bottom plate 4 is constructed with a first clearance-drilled profile-fixing hole 7, a second clearance-drilled profile-fixing hole 8, a third clearance-drilled profile-fixing hole 9 and a fourth clearance- drilled profile-fixing hole 10, with four corresponding bolts 11a, 12a (only two

bolts are shown in Figure 1b) being passed through profile-fixing holes 7, 8, 9, 10 and interacting with four corresponding flat nuts 13, 14 (only two nuts are shown in Figure 1 b), which nuts 13, 14, in a non-tightened state, can slide in the T-shaped slots 2, 3 in the aluminium profile 1. The profile-fixing holes 7, 8, 9, 10 are counterbored for the heads of corresponding bolts 11 , 12.

When the threads of the bolts 11 , 12 are in engagement with the threads of the nuts 13, 14, but not tightened, the bottom plate 4 can be moved in the longitudinal direction of the slots 2, 3 by the nuts 13, 14 sliding in the slots 2, 3. When the bolts 11 , 12 are tightened, the bottom plate 4 is fixed to the aluminium profile 1 in a required position.

In addition, the bottom plate 4 is designed with a first receiving surface (indicated symbolically by a broken line) 15, a second receiving surface 16, a third receiving surface 17 and a fourth receiving surface 18. In addition, the bottom plate 4 is equipped with a first clearance hole 19 and a second clearance hole 20. All the holes and surfaces 7, 8, 9, 10, 15, 16, 17, 18, 19, 20 run essentially perpendicular to the plane of the main surfaces 5, 6.

Figure 2 shows a moveable plate 21 designed with a first main surface 22 and a second main surface 23, which main surfaces 22, 23 are essentially parallel. In addition, the moveable plate is designed with a first threaded adjusting hole 24, a second threaded adjusting hole 25, a third threaded adjusting hole 26 and a fourth threaded adjusting hole 27. In addition, the moveable plate is equipped with a first clearance-drilled locking hole 28 and a second clearance-drilled locking hole 29. The moveable plate is also equipped with a clearance-drilled fixing hole 30. All the holes run essentially perpendicular to the plane of the main surfaces.

Figure 3a shows how the moveable plate 21 is to be caused to interact with the bottom plate 4 that is fixed in the aluminium profile 1 by bolts 11a, 11b, 12a, 12b, by the second main surface 23 of the moveable plate 21 being

moved towards the first main surface 5 of the bottom plate 4. Two corresponding locking screws 31 , 32 have been passed through the two clearance-drilled locking holes 28, 29 and are to be passed through holes 19, 20. As shown for a locking screw 31 , 32 in Figure 3b, a first spherical washer B1 is placed between the head of each locking screw 31 , 32 and the moveable plate 21 , with the spherical part of the washer facing towards the moveable plate 21. The clearance-drilled locking holes 28, 29 have a spherical seating F1 that interacts with the spherical washers B so that sliding can take place. The locking screws 22, 29 pass through clearance holes 19, 20 and interact with a floating threaded washer B2, that is arranged in an additional counterbore F2 on the second main surface 5 of the bottom plate 4. The threaded washer B2 is locked so that it cannot rotate, so that, when the locking screws 31 , 32 are tightened, the moveable plate 21 and the bottom plate 4 are drawn towards each other.

In addition, four corresponding adjusting screws 33, 34, 35, 36 have been brought into engagement with the threads of the four threaded adjusting holes 24, 25, 26, 27, that have been made in the moveable plate 21. Each adjusting screw 33, 34, 35, 36 is preferably designed with a joint (not shown) that enables the lower part of the screw 33, 34, 35, 36 to be angled in relation to its upper part.

By means of the arrangement described above, the adjusting screws 33, 34, 35, 36 come into contact with corresponding receiving surfaces 15, 16, 17, 18 on the bottom plate 4, whereby the moveable plate 21 comes into contact with the bottom plate 4 via the adjusting screws 33, 34, 35, 36, and only the two locking screws 31 , 32 attach the moveable plate 21 to the bottom plate 4. The adjusting screws 33, 34, 35, 36 are then adjustable in the vertical direction, that is essentially transverse to the planes that are defined by the plane of the parallel surfaces 22, 23.

Four corresponding spiral springs 37, 38, 39, 40 have been placed between the first main surface 5 of the bottom plate 4 and the second main surface 23

of the moveable plate 21 , through which the adjusting screws 33, 34, 35, 36 are passed. The respective ends of the spiral springs 37, 38, 39, 40 rest against recesses 41 , 42, 43, 44 for the springs made in the bottom plate 4 and the moveable plate 21 (not shown), in association with the receiving surfaces 15, 16, 17, 18 and the threaded adjusting holes 24, 25, 26, 27. The spiral springs 37, 38, 39, 40 are arranged to exert a force that urges the bottom plate 4 and the moveable plate 21 apart.

Provided that the locking screws 31 , 32 have not been tightened, the moveable plate 21 can be adjusted in a lateral, vertical and longitudinal direction in relation to the aluminium profile 1 by the adjusting screws 33, 34, 35, 36 being tightened or loosened. When the moveable plate 21 is in the required position, the locking screws 31 , 32 are tightened, whereby the receiving surfaces 15, 16, 17, 18 are pressed against the adjusting screws 33, 34, 35, 36. In this way, the moveable plate 21 can be adjusted in relation to the bottom plate 4 and can be moved freely, that is in any direction and at any angle in the x-, y- and z-axes. In other words, the invention is not limited to an adjustment of a moveable plate only in a given x- or y-direction.

The spherical washers B that slide against corresponding spherical seatings F enable a good transfer of force to be obtained between the heads of the locking screws 31 , 32 and the moveable plate 21. The plates 4, 21 thereby constitute an integrated, adjusted unit to which other units can be attached.

One such unit is preferably a milled model body component 45, such as, for example, a bonnet, which is shown in Figure 4. The model body component 45 consists initially of a blank of suitable material, on which a number of supporting surfaces 46, 47, 48, 49 are milled. The supporting surfaces 46, 47, 48, 49 are used as fixing points when the model body component 45 is held in a milling machine via a threaded hole 50, 51 , 52, 53 and suitably designed guide in each supporting surface 46, 47, 48, 49, which milling machine mills the structure of the model body component 45. By this means,

the positions of the threaded holes 50, 51 , 52, 53 in the supporting surfaces are very well defined.

Each supporting surface 46, 47, 48, 49 is moved to fit against a corresponding adjusted moveable plate 21 that is locked in position, as shown in Figure 5, so that a fixing screw 54 that has been pre-inserted through the clearance-drilled fixing hole 30 can be brought into engagement with the threads of the threaded hole 50, 51 , 52, 53 in the supporting surface 46, 47, 48, 49. As a result of the first main surface 5 of the bottom plate 4 being provided with a screw head seating 55 in the form of a groove, a tightening tool can be inserted between the bottom plate 4 and the moveable plate 21 essentially parallel with the main surfaces 5, 6. The fixing screw 54 is then tightened by means of the tightening tool, so that the supporting surface 46, 47, 48, 49 and the first main surface 22 of the moveable plate 21 are pressed towards each other.

In this way, all the supporting surfaces 46, 47, 48, 49 on the model body component 45 are attached to corresponding moveable plates 21 on the relevant chassis components 1 , with a number of chassis components 1 together constituting a chassis structure.

The adjustment of each moveable plate 21 is carried out, for example, by some form of measuring instrument being attached to the first main surface of the moveable plate, against which the supporting surfaces will later rest. The measuring instrument can, for example, be a measuring machine, a milling machine and a beam system with coordinate holes.

In a variant of the described embodiment, with reference to Figure 6, the bottom plate 4', that is shown in a simplified embodiment in Figure 6, is constructed with a first screw holder 55, a second screw holder 56, a third screw holder 57 and a fourth screw holder 58, with the said screw holders 55, 56, 57, 58 consisting of external pillars at the corners of the long sides. In addition, the bottom plate is provided with a fifth screw holder 59 and a sixth

screw holder 60, which fifth and sixth screw holders 59, 60 consist of external pillars on the short sides. All the pillars 55, 56, 57, 58, 59, 60 are provided with threaded screw holes 61 , 62, 63, 64, 65, 66. Six corresponding additional locking screws 67, 68, 69, 70, 71 , 72 can be screwed to the adjusted moveable plate (not shown in Figure 6) through the screw holes 61 , 62, 63, 64, 65, 66, so that the load of these screws 67, 68, 69, 70, 71 , 72 results in additional locking of the position of the moveable plate.

Figure 6 also shows locking nuts 73, 74, 75, 76, 77, 78, designed to be threaded onto the six additional locking screws 67, 68, 69, 70, 71 , 72 from the side of the pillars 55, 56, 57, 58, 59, 60 that faces towards the adjusted moveable plate, so that, when the locking nuts 73, 74, 75, 76, 77, 78 are tightened towards the pillars 55, 56, 57, 58, 59, 60, they lock the six additional locking screws 67, 68, 69, 70, 71 , 72. In order to make room for the locking nuts 73, 74, 75, 76, 77, 78, corresponding recesses are made in the moveable plate (not shown). The number of screw holes can, of course, vary, preferably from two upwards.

The invention is not restricted to the example described above, but can be varied freely within the framework of the invention. For example, the number of holes for the different screws can vary, for example the number of locking screws can be four and the number of fixing screws can be two. The fixing screws can be supplemented by locating pins that pass through corresponding locating holes (not shown) in the moveable plates and respective supporting surface. The number of adjusting screws can also vary, but should not be less than three in order to make sufficient adjustment possible.

The adjusting screws 33, 34, 35, 36 that are engaged in threads in the moveable plate 21 and are in contact with receiving surfaces 15, 16, 17, 18, can equally well (not shown) be engaged in threads in the bottom plate 4 with, in addition, the heads of the adjusting screws 33, 34, 35, 36 being in contact with flanges on corresponding clearance holes in the moveable plate

21 , which flanges admit the passage of an adjusting tool such as a screwdriver or the like.

The adjusting screws 33, 34, 35, 36 can be designed as an integrated unit, with each adjusting screw 33, 34, 35, 36 or the said integrated unit constituting an adjustable element.

The chassis structure can be of many kinds, but it functions primarily as a supporting structure.

The model body components can be any kinds of model structure that are to be fitted to a supporting structure, and do not need to be related to the vehicle industry. For example, the invention can be utilized with all kinds of model where items are put in a precise position in a coordinate system or in relation to each other.

The embodiment with spherical washers for the locking screws 31 , 32 can be varied, the object being to achieve a good transference of force between the locking screws 31 , 32 and the moveable plate 21.

The embodiment with a joint in the adjusting screws can also be varied, the object being to achieve a good adjustment even for oblique angles between the main surfaces 5, 6 of the bottom plate and the main surfaces 22, 23 of the moveable plate.

In addition, the four spiral springs 37, 38, 39, 40 are not necessary for the invention, but are only one example of how the adjustment can be carried out.

The bottom plate 4 and the moveable plate 21 do not need to be in the form of plates, but can consist of any element that has a design that is suitable for the purpose.

The locking screws 31 , 32 can comprise or be a part of the said at least one adjustable element 33, 34, 35, 36.