MX2011013886A - Light sleigh structure for impact test bench for complete vehicle. - Google Patents

Abstract

The present invention refers to a sleigh-type structure for impact test bench for complete vehicle with a light design and great rigidity, which main body is made of cast aluminium able to resist and support up to 80 G of acceleration and up to 1600 kg of total weight, which also has a magnificent rigidity in the vertical direction, it also being resistant to high conditions of mechanical stress, resistant to impacts and extra light. The inventive structure comprises: a) a main base of aluminium in a single piece for receiving the body of the vehicle to be tested, b) a low friction rolling-anchoring subsystem for allowing the body of the vehicle to be displaced over the structure rails, this including safety means for preventing the sleigh from coming off the rail due to the impact, c) an impact bumper and d) a coupling member of hyper-elastic material for absorbing the forces resulting from the impact, which is coupled to the impact bumper and the main base by means of screws. The ma in base offers a space for housing the data acquisition systems and transducers for measuring the impact data.

Description

LIGHTWEIGHT STRUCTURE FOR SHOCK PROOF BANK FOR COMPLETE VEHICLE Field of the Invention The present invention relates to test apparatus for impact testing on vehicles used in testing vehicle safety components.

Background of the Invention The safety of vehicle occupants is one of the main concerns of the automotive industry. To guarantee such safety to passengers, the automotive industry develops tests on assembled cars; to carry out this type of tests, prototypes of all the components of the automobile must exist, and to meet the safety standards of a single component, several tests must be developed, which makes this method of validation quite expensive and time consuming.

Conventional methods for assessing the structural integrity and / or function of safety components in vehicles consist of test benches that simulate frontal, side or reach collision; being the frontal shock the one that presents the most extreme conditions, which can reach decelerations of up to 80 gravities. These test benches simulate the conditions found in a real crash with quite accuracy.

Currently, a test bench for frontal crash simulation consists of: a) a pneumatic propulsion system, b) a transport system or sled and c) an energy dissipating system or shock absorber, which operate as follows: a) the pneumatic propulsion system is responsible for providing energy, using compressed air, to move the entire transport system and provide the standardized test speeds, 56.6 km / h or 64 km / h, and consists of a compressor air, electromagnetic valves, ducts, pistons and a control system. The pistons are located inside ducts that are on the sides of the rails; the pistons are attached to flexible cables that exit from the ends of the ducts, these cables are joined to the sled forming a closed mechanical circuit. The transmission of the movement towards the sled occurs when the pistons are displaced by introducing high pressure air at the ends of the ducts, and since the pistons are attached to flexible cables, they are tensioned with respect to the sled, and in this way all the force or pneumatic energy is transformed into mechanical force applied to the base of the sled that puts it in motion and accelerates until reaching the desired test speeds. b) the transport system or sled consists of a subsystem of bearings that allows to move the sled without friction on the rails; The transport system includes a main structure where the bodywork of a car is assembled, together with the necessary accessories for the test. This body is reinforced with a metal"PANZER" tubular structure so that the body can be used for several tests without suffering excessive deformations and thus reduce costs. The main base must also contain the data acquisition systems that will be responsible for storing the signals coming from the transducers (accelerometers). These data acquisition systems and transducers are responsible for measuring and storing the accelerations and / or forces that occur during the shock simulation. Said sled along with all accessories, data acquisition systems, etc. They present a center of gravity that is desirable to be as close to the floor as possible in order to increase the stability of the assembly. Said sled moves on rigid rails anchored to the floor and at the end of the tour of the sled on the rails, this must already have the specified test speed, and when the sled is hit with the energy dissipating system just at the end of the route, it withstands forces resulting from the longitudinal impact and moments resulting from this force with the lever arm of the entire mass of the transport system, located at its center of gravity. This transport system also has a sub-system of vertical anchoring with the rails to ensure that it does not take off from the rails due to the moment of the collision. One of the main problems of the current systems is that they have a very high center of gravity, which produces very large moments so the anchoring system must be very robust so that the sled does not go off. At present, these sledges are manufactured in steel to withstand the great forces generated during the simulation of the crash, which results in a very heavy sledge. The current transport systems are manufactured with commercial steel structural profiles that have very good resistance characteristics, and must be joined by means of welding, which affects the steel's own resistance due to the thermal shock that the welding implies. When manufactured with commercial profiles, there is little possibility of optimizing the geometry of free form to be able to support the loads that are generated, resulting in over-designed sledges and low rigidity in the vertical direction. Current designs of sleds for frontal crash test benches usually have a flat, lightweight design, resulting in very low vertical stiffness; Being flat, they raise the center of gravity of the entire transport system, generating great moments resulting from shock. c) The energy dissipating system is at the end of the rails where the sled reaches its test speed. This system is responsible for braking the sled by means of a stepper damper that brakes the sled by exerting a force or pulse of modulated and controlled force to simulate the conditions that arise in the actual crash. This pulse of modulated force can decelerate the sledge to magnitudes of 80 gravities.

Conventional sleds are usually manufactured in steel, as this material has good rigidity and longitudinal strength (sense of frontal impact), however, this type of steel sled is quite heavy and requires welding joining methods that weaken the structure. When developing this type of tests the entire bank has a total weight capacity such that if the sled is very heavy, the effective load for the components, accessories, measuring systems, dummies (dummies), etc. It is limited. By reducing the weight of the sled, without sacrificing its strength and rigidity, a greater weight is allowed for the safety components to be validated.

One of the main technical problems in the automotive industry is to be able to increase the number of components to be evaluated in the same test, which results in an increase in the load on the transport system and therefore the forces that are generated are greater and areas where welding has been applied are under greater effort and the possibility of failure is greater.

In this regard, US 5,483,845 (Stein, et al., 1996) discloses an apparatus of a method used to perform crash tests laterally, in this invention a wheelbarrow mounted on a sled is used which moves from longitudinal way; In this apparatus, aluminum panels are used to absorb the impact energy. Likewise, the patent US 5, 485,758 (Brown, et. Al., - - 1996) describes an apparatus for side impact tests which has, among other parts, a door whose structure is formed by aluminum tubes.

On the other hand, US 5,706,908 (Sakai, et al., 1998) describes a structure for absorbing an impact applied to the structure of a collision vehicle using an impact absorbing body made of aluminum and resin. In this same sense, the patent application WO / 2010/109405 (Di Modugno, 2010) describes a bumper that in its structure has two shock boxes made of polymer, likewise has two connecting rods which are made of aluminum and / or alloys of this metal.

In addition, the patent US 5,729,463 (Koenig, et. Al., 1998) reveals the process for the production of the body of a vehicle, the body has the main characteristic of being light, the materials of which the car's structure is made are aluminum, synthetic materials, plastics, among others. Likewise, patent EP 2017364 (Beslin, et al., 2009) also describes the use of aluminum alloys to form the structure of a car, this document is mainly directed to the design of the preparation of said alloys; This document also reveals the use of alloys that will allow the absorption of energy during a collision or shock.

Summary of the Invention In view of the problems in the field, it is an object of the present invention to provide a sledge-type structure of shock-proof banks for complete vehicle.

It is another object of the present invention to provide a sled-like structure of shock test benches for a complete vehicle capable of withstanding and withstanding up to 80G of deceleration and up to 1,600 Kg of total weight.

It is still another object of the present invention to provide a sled-type structure for a complete vehicle impact test bench, which is extra-light, highly resistant, and of excellent rigidity in the vertical direction, in addition to being resistant to high mechanical stress conditions. and that is composed of few pieces.

The present invention relates to a sledge-type transport system for crash tests, consisting of an iron nose, a rubber coupler, a cast aluminum main base and a low friction bearing and anchor system. The main purpose of this invention is that the base has little mass and thus minimize the weight thereof and increase rigidity and strength.

The features and advantages of the structure of the present invention will be more apparent in the light of the description that follows and the figures that accompany it, which are intended to be illustrative but not limiting of the scope of the invention.

Brief Description of the Drawings Figure 1 is a side view of a complete vehicle crash test bank, showing the energy dissipating system, transport system, sled and rails.

Figure 2 is a side view of the transport or sled system of the present invention, without the rails, showing the safety components, accessories for the test, aluminum main base, hyperelastic coupler / insulator, nodular iron impact nose, white-in-body, dummy or mannequin anthropomorphic tests and structure to reinforce the body.

Figure 3 is the side view of Figure 2 during shock simulation, with safety components in operation, deployed airbag, safety belt example, to evaluate functional performance or structural integrity.

Figure 4 is an isometric front view showing the assembled structure of the sled.

Figure 5 is a rear view in isometric of the transport system of the invention - - Figure 6 is a front view of the structure of the sledge of the invention.

Figure 7 is a rear view of the structure of the sledge of the invention.

Figure 8 is a top view of the structure of the sled of the invention.

Figure 9 is a cross-sectional view along the axis B-B of the front part of the sled of the invention shown in Figure 8.

Figure 10 is a cross-sectional view along the axis C-C of the front part of the sledge of the invention shown in Figure 8.

Figure 11 is a cross-sectional view along the axis D-D of the sled of the invention, in the transverse ribs.

Figure 12 is a bottom view of the sled of the invention.

Figure 13 is a cross-sectional view along the axis? -? of the sled of the invention shown in figure 6 Figure 14 is an isometric view of the structure of the sled with explosive nose impact, - - Hyperelastic coupler, aluminum main base and left front bearing system Figure 15 is a side view of the structure of the sleigh of the invention, with impact nose explosive, hyperelastic coupler, aluminum main base and left front bearing system.

Figure 16 is an isometric view showing the sub-system of bearings and anchoring of the sledge of the invention.

Figure 17 is a front view showing the bearing and anchor subsystem.

Figure 18 is a side view showing the bearing and anchor subsystem.

Figure 19 is an isometric explosive view showing the bearing and anchor sub-system, the support plate is observed, two mamelons for fastening to the bolt; bearing, shims, anti-friction anchor bolts and bearings to align and fasten the anchor bolts.

Figure 20 is an explosive front view showing the bearing and anchor sub-system.

Figure 21 is a top view of the impact nose.

- - Figure 22 shows the impact nose with the impact surface and larger coupling surface.

Figure 23 is a front view of the impact nose showing the trapezoidal geometry.

Figure 24 is a side view of the impact nose showing the trapezoidal nature thereof.

Figure 25 is an isometric view of the impact nose with cut along the E-E axis showing the horizontal rib.

Figure 26 shows a side view of the impact nose with cut along the axis E-E.

Figure 27 is an isometric view and cut along the axis F-F of the impact nose, showing the characteristics of the horizontal rib joining the four vertical ribs.

Figure 28 is an isometric view of the hyperelastic coupler.

Figure 29 shows the front view of the coupler (5) hyperelastic Figure 30 is an approximation of the impact nose assembly, coupler and main base, showing the alignment of the external ribs of the impact nose - - with the walls of the main structure of the base and the internal ribs of the impact nose with the internal ribs of the main base.

Figure 31 is a longitudinal sectional view with explosive of the main nose-coupler-base assembly, showing in detail the alignment of the horizontal rib of the impact nose with the horizontal rib of the main base.

Figure 32 shows the first vibration mode of the main base.

Figure 33 shows the second vibration mode of the main base.

Figure 34 shows the third vibration mode of the main base.

Figure 35 shows the fourth mode of vibration of the main base.

Figure 36 shows the fifth mode of vibration of the main base.

Detailed description of the invention The present invention relates to a transport system or sled for simulation of frontal collision of vehicles, which is illustrated in Figures 1-7.

- - The sled (2) is used with a test dummy (8) and is movable by moving on a pair of parallel rails (3) anchored to the floor; the sled (2) consists of a sub-system of bearings and anchoring (1A), said system of bearings allows to move the sled practically without friction on the rails (3), using bearings covered with rubber (15). The bearing sub-system supports all the weight of the sled (2) including the safety components and test accessories (Max 1600Kg).

The transport system or sled (2) includes a main base (4) where the reinforced body of a car (7) is assembled, together with the necessary accessories for the test. Said body is preferably reinforced with tubular structure (9), metallic so that it can be used for several tests without suffering excessive deformations and reducing costs.

The main base (4) also provides space (DAQ-A) for the data acquisition systems that will be responsible for storing the signals coming from the transducers (accelerometers). Said data acquisition systems and transducers are responsible for measuring and storing the accelerations and / or forces that are held during shock simulation.

Said sled (2) with all accessories, data acquisition systems, etc. they produce a center of gravity of the whole system, which is desirable to be as close to the floor.

- - When the sled (2) is operated, it travels on rigid rails (3) anchored to the floor, so that at the end of the run the sled (2) has acquired the specified test speed, and is hit with the heat sink system. energy, receiving forces resulting from this impact in longitudinal form and moments resulting from said force with the lever arm of the entire mass of the transport system.

Said transport system has a bearing and anchor sub-system (1A) composed of a rotating anchor bolt (17) that comes into contact with the rails (3) when the shock develops to guarantee that the sled does not go off.

The structure of the sledge (2) of the present invention has an impact nose (6) which is made with nodular iron casting and provides a high impact resistance. Said impact nose (6) has a trapezoidal design, which includes an impact surface (6b) four vertical ribs (6a and 6 e), a horizontal (6d) and rear coupling wall (6c); the impact surface (6b) receives the strength of the damping system (1), which is channeled to a coupling surface (6c) flowing through the vertical trapezoidal vertical ribs (6e), interior ribs (6a) and trapezoidal horizontal rib (6d) ). With this geometric configuration of the impact nose (6) it is guaranteed that the force per unit area applied to the main aluminum base (4) is smaller. - - The arrangement of the vertical ribs (6a, 6e) and horizontal (6d) of the nose (6) have the same arrangement as the vertical walls (4e), vertical rib (4a) and horizontal (4d) of the main base (4) ), in order to transmit the force to resistant areas and thus avoid excessive bending stresses in the base (4).

The coupling element (5) manufactured in hyperelastic material, such as rubber, is responsible for transmitting the impact force of the nose (6) uniformly to a larger area of the aluminum main base (4).

The purpose of the hyperelastic coupling element (5) is to eliminate the moment or inclination that the shock absorber can transmit, given that during the impact it will suffer a slight buckling. The coupling element (5) is joined by means of floating screws which help in case of inclination of the impact surface of the shock absorber, the moment is not transmitted to the aluminum base and being hyperelastic, as well as absorbing the inclination of the impact nose (6) with respect to the main base (4).

The main base (4) consists of a coupling area (4c) which is responsible for receiving the shock forces and consists of a box-like structure with two vertical walls (4e) extending the entire length of the base; two vertical trapezoidal ribs (4a) projecting to the middle of the base and a horizontal rib (4d) projecting to half the length - - from the base; additionally it comprises five transverse ribs (4f) to provide sufficient transverse, vertical and bending stiffness. The combination of the two longitudinal walls and the five transverse ribs generate five box-like structures that generate a longitudinal, transversal and vertical rigidity necessary for the tests to be developed.

This coupling area (4c) is arranged below the level of the rails (3) to lower the center of gravity of the entire system. The main base further includes structural elements for coupling with the reinforced structure containing the body of the test vehicle. These structural elements are located above the rails (3) and are attached to the structure of the body by means of screws.

The design of the main base is such that, in addition to providing excellent weight and resistance characteristics, it provides an area to safeguard the data acquisition systems safely and as low as possible.

The main base of aluminum (4) is mounted on 6 sub-systems of bearings and anchoring (the) that help you move on the rails (3), fixed to the floor, with very low friction. Likewise, the six sub-systems of bearings and anchor (1A) use bearings (15) with hyperelastic coating that provides a smooth path of the base on the rails (3). The bearings with coating - - Hyperelastic (15) absorb the imperfections of the joints of the rails helping to avoid introducing noise to the test signals, as well as attenuating the vertical excitation that the joints of the rails (3) could provide to the sled.

The sub-system of bearings and anchoring (the), has a vertical anchoring system with the rails composed of rotating bolts (17) mounted on bearings (18), which ensures that in case of contact with the rail ( 3), the friction will be minimal, so also said anchoring systems ensure that the sled (4) does not shoot vertically from the rails. The rotating anchor bolts (18) receive the force exerted by the vertical contact with the rails (3), and this in turn is held by the bearings (18) type journal, which are attached to the coupling plate (12) using screws.

The height of the rotating bolts (17) is adjusted by using the calibrated increase plates (16). The sub-system of bearing and anchor (1A), holds and positions the bearing (15) that comes into contact with the rail (3) by means of a crazy pin (14), which in turn is held with two mamelons ( 13) and these are fastened to the coupling plate (12) by means of screws and the coupling plate (12) to the main base (4) with screws.

The advantages of the design of the main base (4) of this invention and of the selection of material for its manufacture in cast aluminum, are: - - • Resists the weight of the systems that are on it.

• Resists impacts with accelerations of up to -80 gravities.

• Provides good longitudinal stiffness.

· Provides good enough longitudinal buckling rigidity.

• Provides good vertical rigidity.

• Provides quite good vertical buckling rigidity.

• Provides good transverse rigidity.

· Provides good enough transverse buckling rigidity.

• Lower the center of gravity of the entire transportation system.

• Provides secure space for data acquisition systems.

Figures 32 to 35 illustrate different configuration modes that the main base can adopt, where Figure 32 shows a first mode of vibration of the main base; Figure 33 shows a second mode of vibration of the main base; Figure 34 shows a third mode of vibration of the main base, Figure 35 shows a fourth mode of vibration of the main base and Figure 36 shows the fifth mode of vibration of the main base.

Claims (12)

1. A sled-type transport system to be used in front, side or range crash tests of a complete vehicle, characterized in that it comprises: • a main base • a sub-system of low friction bearing-anchor, • an impact nose, • a coupling element made of hyperelastic material, where the body to be tested is mounted on the main base, which runs practically without friction on rails thanks to the subsystem of rolling-anchoring that also keeps the main base on the rails along its length; the impact nose receives the forces produced by the impact of the base, and is anchored to it by means of the coupling element of hyperelastic material that absorbs the force of the impact.
2. A sled type transport system for complete vehicle crash tests, according to claim 1, characterized in that the impact nose is trapezoidal in shape.
3. A sled transport system for complete vehicle crash tests, according to claims 1 and 2, characterized in that the impact nose is preferably made of nodular iron melted by gravity.
4. A sled transport system for complete vehicle crash tests, according to claims 1 and 2, characterized in that the impact nose includes a frontal impact surface, with four vertical ribs, a horizontal rib and a rear coupling wall to be coupled with the coupling element of hyperelastic material.
5. A sled type transport system for complete vehicle crash tests, according to claim 1, characterized in that the main base is preferably made of cast aluminum in one piece
6. A sled-type transport system for complete vehicle crash tests, according to claim 1, characterized in that the main base comprises an impact front wall, two vertical walls extending along the length of the base, two vertical trapezoidal ribs projecting to the middle of the base and a horizontal rib projecting to half the length of the base.
7. A sled transport system for complete vehicle crash tests, according to claims 1 and 6, characterized in that the main base further comprises five transverse ribs to provide transverse, vertical and bending stiffness.
8. A sled-type transport system for complete vehicle crash tests, according to claim 1, characterized in that the vertical and horizontal ribs of the impact nose have the same arrangement as the vertical walls, vertical and horizontal ribs of the main base to transmit the force to resistant areas and avoid excessive bending stresses in the base.
9. A sled-type transport system for complete vehicle crash tests, in accordance with claim 1, characterized in that the low friction bearing and anchor subsystem includes journal bearings with hyperelastic coating.
10. A sled type transport system for complete vehicle crash tests, according to claim 1, characterized in that the low friction bearing and anchor subsystem includes a vertical anchoring mechanism composed of rotating anchor bolts that prevent the sled from coming out of the rails as the impact develops.
11. Jn sledge transport system for complete vehicle crash tests, according to claims 1 and 10, characterized in that the subsystem of bearings and low friction anchor holds and positions the bearing in contact with the rail by means of a bolt in loco , fastened by two mamelons that are fastened to the coupling plate by means of screws.
12. 12. A sled type transport system for complete vehicle crash tests, according to claim 1, characterized in that the main base is mounted on 6 low friction bearing and anchor subsystems, attached thereto by means of screws. A sled type transport system for complete vehicle crash tests, in accordance with claim 1, characterized in that the main base provides the necessary space to house the data acquisition systems and transducers that measure and store the impact data. A sled transport system for complete vehicle crash tests, according to claim 1, characterized in that the impact zone of the main base is located below the level of the rails, providing a center of gravity of the system sufficiently low to grant a high stability. A sled transport system for complete vehicle crash tests, according to claim 1, characterized in that the coupling element is made of a hyperelastic material such as rubber. A sled transport system for complete vehicle crash tests, according to claim 1, characterized in that the hyperelastic coupler is joined to the base and the nose by means of floating screws. SUMMARY OF THE INVENTION The present invention relates to a sledge-type structure for impact test bench for complete vehicle with lightweight design and high rigidity whose main body is made of cast aluminum, able to withstand and withstand up to 80G of deceleration and up to 1 600 Kg of total weight, which also presents magnificent rigidity in the vertical direction, in addition to being resistant to high mechanical stress conditions, it is highly resistant to impacts and is extra light. The sled structure comprises: a) a main base, aluminum in one piece, to receive the body to be tested, b) a subsystem of low friction bearing-anchor, to allow the movement on rails of the structure and includes means of safety to prevent the exit of the sled from the rails by impact, c) an impact nose and d) a coupling element of hyperelastic material to absorb the forces resulting from the impact, which is coupled to the nose and the main base by means of of screws. The main base offers a space to house the data acquisition systems and transducers for the measurement of impact data.