Description

REBOUNDING PREVENTION DEVICE OF ROADWAY

SAFETY GUARD

Technical Field

[1] The present invention relates to a roadway safety guard installed on a roadway at which a vehicular impact is expected, such as the entry of a branched road, the entry of a center barrier or the entry of a tunnel, the safety guard absorbing the impact energy by the return back movement of the cushion means on vehicular collision, and more particularly to a roadway safety guard having a rebounding prevention device, which prevents the impacting vehicle from spring back due to the repulsive power of the cushion means and minimizes the possibility of secondary collision.

[2]

Background Art

[3] Generally, there are several types of roadway safety facilities installed on the road, which can increase the safety of traffic on the accident. For instance, guard rails are installed along both shoulders of the road to protect vehicles from deviating from the road. Also, median dividers are installed along the center lane of the road for preventing vehicle entering into the opposite lane.

[4] Further, safety guards or crash cushions are installed at the entrance of a road branched by the facilities such as underground roadways, overhead roads, tunnels, bridge posts and toll booths. The safety guards prevent the vehicle from directly colliding onto the facilities, and protect themselves against vehicular impact as well as protecting passengers during a car crash.

[5] The guard rail and the median divider are seldom hit head-on with a vehicle as they are positioned parallel with the road. However, the safe guard is apt to be hit head-on with vehicles since it is located in front of the driving direction of oncoming automobiles.

[6] In the event of a head-on collision with the safe guard, enormous impact energy is applied to the vehicle which can result in a fatal blow to the vehicle and passenger. Therefore, it is desirable that the safe guard effectively absorbs kinetic energy of an impacting vehicle to minimize injury of passengers and to reduce damage to roadway facilities as well as the vehicle.

[7] However, a common type of safety guard is formed by a concrete structure, steel guard rail or a cushion using worn tires or polyurethane foam. As these structures are installed in a stationary manner on the road, these can not effectively absorb the enormous impact energy generated by the collision. Therefore, it is limited to reducing

the amount of damage cost of a traffic accident.

[8] To overcome these problems of the conventional safety guard, various vehicular impact absorbing apparatuses have been proposed, for example, in U.S. Pat No. 6,905,291 (Korean Patent No. 0405957), which is assigned to the present inventor.

[9] As shown in Figs. 1 and 2, a pair of tubular guide rails 1 is fixed to the road "R" each of which has a guide slit Ia on the top portion of the guide rail 1. A group of sliders 2 each having a web 2a is positioned in the guide rail 1 at a predetermined interval. The web 2a is extruded up through the guide slit Ia. Several cushion pins 4 are provided at the guide rail 1 at a predetermined interval, and are located at a place between each slider 2. A cushion unit 3 that is evenly stacked by worn tires 3a is placed along the slider 2.

[10] As shown in Fig. 3, the sliders 2 move backward as vehicle collides into the safety guard. The cushion pins 4 are cut successively as shown in Fig 4, and the cushion units 3 are compressed in a manner to absorb the shock energy effectively. The remaining numeral 7 is an exterior cover, and numeral 6 is a side fence for the preparation against a side collision.

[11] However, the cushion units 3 compressed by vehicular collision exert the repulsive power into themselves, and bring the concern of the bounding force to vehicle generated by the cushion unit 3. In the conventional technology, several cushion pins 4 are provided at the tubular guide rail 1 in a horizontal manner, and each pin's middle portion is designed to cut. Thus, the repulsive power of the cushion unit 3 might be somehow absorbed by the cut cushion pin 4. It is still unsatisfactory to obtain the full absorption of repulse. Danger of a secondary collision caused by repulse has no choice but to exist.

[12] Korean Patent No. 0516808 is one example illustrating the roadway safety guard, in that the impact absorbing unit moves backward in the collision direction, so that the impact energy can be absorbed by the cutting of the wire rods and deformation of the elastic means. In this technology, the wire rods to be cut are vertically connected with the links of the impact absorbing device formed in a pantograph. Thus, it is hard to control the repulsion caused by the repulsive force of the elastic means, and the collided vehicle is sprung back onto the roadway. This leads to a secondary collision with other driving vehicle.

[13]

Disclosure of Invention Technical Problem

[14] It is an object of the present invention to provide the roadway safety guard having a rebounding prevention device to solve various problems being exposed in the prior art.

[15] It is an object of the present invention to provide the roadway safety guard having a rebounding prevention device, in which several impact absorbing units move backward along the rail, so the vehicular collision and the cushion unit of the roadway safety guard can absorb the impact energy and be deformed due to the impact energy.

[16] It is an object of the present invention to provide the roadway safety guard having a rebounding prevention device, in which it is surely possible to prevent the vehicle from being sprung back into the traffic owing to the restoration force of the cushion unit and it minimizes the concern of a secondary collision with another vehicle.

[17]

Technical Solution

[18] In order to accomplish the above objects, the prevent invention is comprised of the following: In a roadway safety guard having a pair of guide rails fixed on the road in a parallel way, and several cushion units disposed on each guide rail in a predetermined interval, and being moved along the vehicular collision and being deformed to absorb the impact energy, a rebounding prevention device of the roadway safety is comprised of a shaft having a control lever at one end of the shaft, being inserted into a pair of the guide rails in a perpendicular direction; at least one locker fixed on the shaft, and contacting with the front edge of the cushion unit and blocking the cushion unit's return by elastic rebounding after vehicle collision; and an elastic means for actuating the locker upward so as for the locker to contact with the front edge of the cushion unit retreated by vehicular collision.

[19] In accordance with a preferred feature of this invention, each group of the rebounding prevention device is successively positioned at a predetermined interval along the guide rail. Regardless of the return magnitude of the cushion unit with respect to impulse energy of vehicle, the value of return by the elastic impulse can be controlled.

[20]

Advantageous Effects

[21] Using the present invention, several impact absorbing units move backward along the rail during the vehicular collision, and the cushion unit of the roadway safety guard can absorb the impact energy and be deformed due to the impact energy. It is assured to prevent spring back of the vehicle onto the traffic due to the restoration force of the cushion unit. It minimizes the concern of a secondary collision with another vehicle.

[22] Therefore, this invention has an excellent effect that the safety and reliability of the roadway safety guard can be increased and the maintainability can be performed easily, and more causalities can be reduced.

Brief Description of the Drawings

[24] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[25] Fig. 1 is a side view illustrating one embodiment of a roadway safety guard;

[26] Fig. 2 is an enlarged cross-sectional view along line II-II of Fig. 1 ;

[27] Figs. 3 and 4 are a side view and a plan view showing operation of the roadway safety guard, respectively;

[28] Fig. 5 is a disassembled perspective view showing a rebounding prevention device of the present invention;

[29] Fig. 6 is a side view showing the a rebounding prevention device attached on the roadway safety guard;

[30] Fig. 7 is an enlarged cross-sectional view along line VI-VI of Fig. 6;

[31] Fig. 8 is a partial cut off side view of the rebounding prevention device along line

Vn of Fig. 7;

[32] Figs 9 to 11 show sequentially the operation of the rebounding prevention device of the present invention; and

[33] Fig. 12 is a side view illustrating other embodiment of a roadway safety guard.

[34]

Best Mode for Carrying Out the Invention

[35] This invention will be described further by the way of exemplary embodiments with reference to the accompanying drawings.

[36] In the following explanation, the present invention will be explained by making reference to U.S. Pat. No 6,905,281 which is invented by the present applicant.

[37] In Figs. 5 to 8, a roadway safety guard having a rebounding prevention device 10 as the present invention is comprised of a pair of parallel tubular guide rails 1 each having a longitudinal guide slit Ia on the upper portion of the guide rail 1 and fixed on the ground "R"; several sliders 2 provided in the guide rail 1, each slider 2 positioned at a certain interval, and the upright portion of each slider 2 protrudes through the guide slit Ia; and several cushion units 3 comprised of a stack of tires 3a placed around the exposed portion of the slider 2 to the outside of the guide rail 1.

[38] Furthermore, a roadway safety guard having a rebound prevention device 10 as the present invention is comprised of several impact absorbing pins 4 positioned in the guide rail 1 at the location between the adjacent sliders 2, and being successively broken by the slider 2 moving backward during a car crash; and a stopper 5 provided at the rear of the guide rail 1 to block the return back of the cushion unit 3.

[39] The rebounding prevention device 10 is comprised of a horizontal shaft 11

penetrated perpendicular to a pair of guide rails 1 ; a couple of lockers 12 which are fixed on the shaft 11 so that each locker 12 can be positioned in each guide rail 1, and prevents the slider 2 that is retreated by the car crash from coming back to its initial state due to the restoring force of the slider 2; and an elastic means 13 for actuating the locker 12 upward so as to block the slider 2 from returning back.

[40] The shaft 11 is inserted into the assembly hole Ib that is provided at the lower portion of each guide rail 1. A snap ring 15 is placed on the exterior side of each assembly hole Ib so that the shaft 11 can not break loose from the assembly hole Ib. Otherwise, not shown in the embodiment, a nut instead of the snap ring 15 can be used.

[41] The reason why the shaft 11 is provided at the lower position of the guide rail 1 is that it does not interfere with the movement of the slider 2 that protrudes through the slit Ia, and provides an effective block to the slider's return by elastic rebound after a vehicle collision.

[42] At one end of the shaft 11 is provided a control lever 16 that can rotate the locker

12 in a downward direction to allow the slider 2 blocked by the locker 12 to reset to the initial position for repair work. The control lever 16, as shown in Fig. 5, can be shaped with a bend, or an additional handle can be provided, which is not shown in here.

[43] The locker 12 can be shaped in an almost rectangle, and have an assembly hole 12a offset to one end of the locker 12. The shaft 11 is inserted through the assembly hole 12a. The locker 12 can be fixed on the shaft 11 by a bolt 17, both of which can be incorporated. Furthermore, a protrusion 12b is provided on one side of the locker 12, which can support one end of the elastic means illustrated below.

[44] The elastic means can be made in several ways, for instance, a torsion spring 13, as shown in drawing, can be employed. One end of the torsion spring 13 is contacting the floor of the guide rail 1, and another end of the torsion spring 13 is contacting the protrusion 12b of the locker 12. The protrusion 12b of the locker 12 always is pushed upward.

[45] Herein, to assure both the block of elastic return of the backward moving slider 2 due to a vehicular collision and the non-blocked movement of the slider 2, maximum angle exerted by the torsion spring 13 is preferably within 90 against the floor of the guide rail 1. On the floor of the guide rail 1 is provided a stopper 14 that can limit the rotational angle of the rocker 12.

[46] With this construction, when the locker 12 is rotated at a maximum angle by the torsion spring, the upper free end of the locker 12 is placed at a slant manner toward the upper rear of the guide rail 1.

[47] Only one rebounding prevention device can be provided at the predetermined area of the guide rail 1, which can block the return of the slider 2 by elastic rebounding. The value of return of the cushion unit 3 can be different depending on the speed, weight

and the collision direction of vehicle. To get an effective rebounding block, several rebounding prevention devices 10 can be employed, that are arranged at a predetermined interval along the guide rail 1.

[48] The magnitude of return of the cushion unit 3 can be varied according to the size of the impulsive energy caused by the collision. Regardless of the return magnitude, the value of return by the elastic impulse should be controlled. To achieve this purpose, each group of the rebounding prevention device 10 is successively positioned at a predetermined interval along the guide rail 1.

[49] The widths S 1 ~S 4 of each rebounding prevention device 10 are determined so that they are gradually decreased (S ) s ) s ) S ) proceeding in the rearward direction. Going toward the rear of the guide rail 1, the velocity and the impulsive energy of the vehicle are gradually decreased with respective to those produced at the initial collision. This leads to a reduced value of the return of the cushion unit 3, which makes an effective retardation against repulsion.

[50] The operation of the above roadway safety guard having a rebounding prevention device 10 will be described with reference to Figs. 9 to 11.

[51] Fig. 9 shows that there is no collision with the roadway safety guard. At this state, the locker 12 of the rebounding prevention device 10 is contacted under the bottom of the slider 2, by which the locker 12 is pressed down a little.

[52] When the vehicular collision happens, the slider 2 including the cushion unit 3 breaks the cushion pins 4 and moves toward the rear of the guide rail 1, which absorbs the impact energy due to the collision. As shown in Fig. 10, the slider 2 has passed by the location of the locker 12. The locker 12 is in a free state. The locker 12, pressed down by the slider 2, rotates upward by the elastic restoration of the torsion spring 13. The upper free end of the locker 12 is placed above the bottom of the slider 2.

[53] If the slider 2, after the collision, tries to move forward or move to its initial position due to the elastic restoration of the cushion unit 3, the rear end of the slider 2 is blocked by the upper free end of the locker 12, so that it cannot move forward.

[54] Therefore, it surely prevents the spring back of the vehicle into the traffic due to the repulsive power of the cushion unit 3.

[55] During the repair after settling the accident, the control lever 16 of the shaft 11 is pressed down as shown in Fig. 11. The locker 12, which is integrally fixed with the shaft 11, is also rotated downward so that the restriction is cleared and the slider 2 can be released. Thus, the slider 2 moves in the forward direction or move to the initial position due to the restoration force of the cushion unit 3.

[56] The above embodiment has only illustrated the rebounding prevention device 10 that can be disposed at the lower portion of the slider 2. It has been described for illustrative purpose, and it is not intended to be limited to the particular forms disclosed.

It is not mention that the rebounding prevention device 10 can be installed in another place depending on the type or construction of the roadway safety guard that should be applied.

[57] For instance, as shown in Fig. 12 that is shown in the patent designated to the present applicant, the rebounding prevention device 10 can be provided at the place between the slider 2 and the neighboring slider 2. In this case, the locker 12 rotates at a maximum angle, and the upper free end of the locker 12 is disposed above the lower portion of the slider 2. However, since the locker 12 is provided at a slant rearward, it never interrupts when the slider 2 retreats. The operation of the rebounding prevention device is identical to that shown and described in Figs. 9 to 11.

[58]

Industrial Applicability

[59] As described above, according to the roadway safety guard having a rebounding prevention device of this invention, several impact absorbing units move backward along the rail during the vehicular collision, and the cushion unit of the roadway safety guard can absorb the impact energy and be deformed due to the impact energy. It is assured to prevent spring back of the vehicle onto the traffic due to the restoration force of the cushion unit. It minimizes the concern of a secondary collision with another vehicle.

[60] Therefore, this invention has an excellent effect that the safety and reliability of the roadway safety guard can be increased and the maintainability can be performed easily, and more causalities can be reduced.