The technical field of the invention is that of 5 devices for reinforcing the floors of vehicles against the explosion effects of mines.
More particularly, the invention relates to the vehicles comprising torsion bars arranged under the floor.
It is known to provide military vehicles with 10 damper devices comprising torsion bars. These torsion bars are transversal to the vehicle and are secured to it by one of their ends while the other end is secured to a trailing arm allowing the displacement of a wheel- or track roller-type ground-contacting member. The thus-connected bar is 15 under torsion loading and ensures the return movement of the trailing arm during its oscillations.
On the vehicles provided with bars crossing the passenger compartment of the vehicle, in case of a mine explosion under the vehicle, the floor is distorted and 20 applies a bending stress on the bar located just above it.
The bar is impacted by the floor, it breaks and projects splinters that are hazardous for the occupants of the vehicle.
To remidy this, it is known to place the torsion 25 bar outside of the passenger compartment, making it pass just under the floor.
This solution allows to avoid the risks of projecting splinters but the distortion of the floor is then no longer limited by the torsion bar. The floor itself 30 is distorted towards the interior of the passenger compartment and it can impact the occupants of the vehicle. 2
A solution is provided by patent EP1081451 which provides a complementary module placed under the vehicle. This module comprises a second floor onto which are placed side-members which support the suspending and ground-contacting means such as the torsion bars. This device has 5 the drawback of being extremely heavy and cumbersome, thus penalizing the crossing and mobility capacities of the vehicle.
Patent CH401757 describes an assembly of torsion bars below an armored vehicle body. The bars are secured by 10 their supporting ends connected to longitudinal side-members arranged under the body on either side of the vehicle. However, the bottom of the body of this vehicle is absolutely not protected from the blast of a mine.
Patent application WO03/004335 discloses an armored 15 vehicle comprising torsion bars arranged under the floor of the vehicle and protected from the effects of a mine explosion by a protecting module provided under the torsion bars and at a distance from them.
The invention aims to solve the problem of 20 reinforcing a floor of an armored vehicle comprising torsion bars.
Advantageously, the device according to the invention reinforces the vehicle against the attacks of mines without significantly penalizing the mass and volume 25 of the vehicle.
The invention relates to a device for reinforcing a floor of a vehicle against the explosion effects of mines, the vehicle comprising at least one torsion bar arranged under said floor, the device being characterized by the 30 fact that it comprises at least one retaining means designed to be secured to the lower face of the floor, the retaining means formed by a flange comprising at least one 3
opening designed to surround a lower part of at least one torsion bar, the flange being fixed directly to the lower face of the floor so that the one or more torsion bars oppose to a distortion of the floor towards the interior of the passenger compartment. 5
According to a feature of the invention, the flange comprises two openings each surrounding a lower part of a torsion bar.
According to a feature of the invention, the flange completely surrounds the one or more torsion bars. 10
Advantageously, the flange comprises at least one immobilization shim arranged in the opening between the floor and a torsion bar.
Advantageously, there is a clearance between the flange and the torsion bar, the clearance enabling a 15 rotation of the bar with respect to the device.
Advantageously, the retaining means are regularly distributed along each bar.
The invention also relates to a vehicle comprising a floor and at least one torsion bar arranged 20 under said floor, the vehicle being characterized by the fact that it comprises a reinforcement device comprising at least one retaining means securable to the lower face of the floor, the retaining means formed by a flange comprising at least one opening surrounding a lower part of 25 at least one torsion bar, the flange being fixed directly to the lower face of the floor so that the one or more torsion bars oppose to a distortion of the floor towards the interior of the passenger compartment.
The invention will be better understood upon 30 reading the following description, the description made with reference to the appended drawings in which: 4
- Figure 1 shows a cross-section view of a vehicle comprising a reinforcement device according to the invention ;
- Figure 2 shows a detailed view along the longitudinal section AA of the preceding figure ; 5
- Figure 3 shows a detailed view along the longitudinal section AA of Figure 1 for a device according to a second embodiment ;
- Figure 4 shows a cross-section view of a vehicle according to the invention subjected to a mine 10 explosion ;
- Figure 5 shows a detailed view along the longitudial section AA of Figure 1 for a device according to a third embodiment.
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According to Figure 1, a tracked armored vehicle 100 comprises a body 101 suspended by transverse torsion bars 10 associated with dampers (not shown). The body 101 comprises susbtantially vertical side flanks 101a extending as far as under the floor 101b of the vehicle. 20
Each torsion bar 10 is secured to a flank 101a of the floor 101b by an end 10a and it is secured to a trailing arm 104 by its other end. The trailing arm 104 ensure the connection with a roller 20 which guides the track 105. 25
The torsion bars 10 are provided under the floor 101b. The underside of the floor comprises a reinforcing device according to the invention which comprises retaining means 1 secured to it. Two retaining means 1 per torsion bar 10 are regularly distributed along each bar and 30 surround the lower part of each bar 10.
According to a first embodiment shown in Figure 2, each retaining means 1 comprises a U-shaped flange 2, 5
the U-opening 3 of which is directed towards the floor 101b of the vehicle 100. The opening 3 receives the lower part of a torsion bar 10 and it surround its lower part. This flange 2 is preferably made of a steel of a hardness lower than that of the torsion bar to allow a possible peening of 5 the flange 2 by the bar 10 and not the other way around.
An immobilization shim 4 is provided in the opening 3 between the floor 101b and the torsion bar 10. A clearance J is provided between the torsion bar 10 and the flange 2 as well as between the torsion bar 10 and the 10 immobilization shim 4. This clearance will be higher than 0.5 mm and lower than 3 mm to enable the free rotation of the torsion bar 10 on itself, while limiting its side displacements towards the floor.
The flange 2 is made directly secured to the 15 floor 101b by means of screws 5 passing through it. The immobilization shim 4 is held in place in the opening 3 by shape matching between lugs 6 of the shim 4 and housings 7 carried by the flange 2.
According to a second embodiment illustrated in 20 Figure 3, the flange 2 comprises two housings 3a and 3b each corresponding with a different torsion bar 10.1 or 10.2. This flange 2 also comprises two immobilization shims 4a and 4b.
According to another embodiment shown in Figure 25 5, the retaining means 1 is formed by a flange 2 which does not comprise an immobilization shim and which has an enlarged opening 3. Two torsion bars 10.1 and 10.2 are provided in this opening 3. This embodiment leaves a displacement freedom to the bars 10.1 and 10.2 both 30 upwardly and horizontally. This solution, while addressing the posed problem, is not the preferred embodiment due to 6
the vibrations and noises the displacement of the bar 10 against the flange 2 may cause.
It would also be possible to define flanges, the one or more openings of which receiving the one or more torsion bars 10 are cylindrical. 5
According to Figure 4, a vehicle 100 undergoes an explosion of a mine 200 under its floor 101b, the explosion generating a powerful blast applying pressure onto the floor 101b. The torsion bars 10, due to their geometry offering very little gripping surface to the blast, are 10 hardly affected by it.
The blast induces a distortion X of the floor 101b towards the interior of the passenger compartment. The torsion bars 10 provide at the retaining means 1 a stress F opposing to the distortion of the floor by the interference 15 of the flange 2 of each means 1 with the bars 10. This stress is all more effective that the bars have a strong resilience. Thus, thanks to the retaining means 1, the lower face of the floor is connected to the torsion bars which are limiting the distortion of the floor. The 20 retaining means (or flanges 2) are arranged at a distance from the ends of the torsion bars 10 to minimize the distortion of the floor.
The overall distortion that the floor 101b would have undergone without the retaining means 1 according to 25 the invention has been represented as a dashed line.
Thanks to the invention, the maximum amplitude X of the distortion of the floor is reduced and much lower that the amplitude D of the distortion of a floor lacking the retaining means 1. 30
The compactness of the retaining means with respect to the prior art only marginally burdens the mass of the vehicle and its crossing capacities. 7
According to the embodiments shown in Figures 2, 3 and 5, the flange 2 comprises sloped sides 2a and 2b to minimize the risks of colliding with possible obstacles passing under the floor 101b.
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We Claim:
1 – A device for reinforcing a floor (101b) of a vehicle (100) against the explosion effects of mines (200), the vehicle (100) comprising at least one torsion bar (10) 5 arranged under said floor (101b), the device being characterized by the fact that it comprises at least one retaining means (1) designed to be secured to the lower face of the floor (101b), the retaining means (1) formed by a flange (2) comprising at least one opening (3) designed 10 to surround a lower part of at least one torsion bar (10), the flange (2) being fixed directly to the lower face of the floor (101b) so that the one or more torsion bars (10) oppose to a distortion of the floor (101b) towards the interior of the passenger compartment. 15
2 – The reinforcement device according to claim 1, characterized by the fact that the flange (2) comprises two openings (3) each surrounding a lower part of a torsion bar (10). 20
3 – The reinforcement device according to any one of claims 1 or 2, characterized by the fact that the flange (2) completely surrounds the one or more torsion bars (10).
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4 – The reinforcement device according to claim 3, characterized by the fact that the flange (2) comprises at least one immobilization shim (4) arranged in the opening (3) between the floor (101b) and a torsion bar (10). 30
5 – The reinforcement device according to any one of claims 1 to 4, characterized by the fact that there is a 9
clearance (J) between the flange (2) and the torsion bar (10), the clearance (J) enabling a rotation of the bar (10) with respect to the device.
6 – The reinforcement device according to any one 5 of claims 1 to 5, characterized by the fact that the retaining means (1) are regularly distributed along each bar (10).
7 – A vehicle (100) comprising a floor (101b) and 10 at least one torsion bar (10) arranged under said floor (101b), the vehicle being characterized by the fact that it comprises a reinforcement device according to any one of the preceding claims, the device comprising at least one retaining means (1) securable to the lower face of the 15 floor (101b), the retaining means (1) formed by a flange (2) comprising at least one opening (3) surrounding a lower part of at least one torsion bar (10), the flange (2) being fixed directly to the lower face of the floor (101b) so that the one or more torsion bars (10) oppose to a 20 distortion of the floor (101b) towards the interior of the passenger compartment.