Procedures for operating a motor vehicle
By using varying adhesives and a laminated glass interlayer with carrier bubbles and particles, the method addresses uncontrolled stress distribution in laminated glass windshields, achieving controlled breakage and reduced injury risk during impacts.
Patent Information
- Authority / Receiving Office
- DE · DE
- Patent Type
- Patents
- Current Assignee / Owner
- DR ING H C F PORSCHE AG
- Filing Date
- 2020-07-17
- Publication Date
- 2026-06-11
AI Technical Summary
Existing motor vehicle safety glazing with laminated glass does not effectively manage the distribution of stress and impact forces, particularly during pedestrian collisions, leading to uncontrolled breakage and potential injury.
The windshield is bonded to vehicle components using varying adhesives and incorporates a laminated glass interlayer with carrier bubbles filled with particles, which upon impact, initiate controlled cracking by releasing fluid and particles to reduce the force required for breakage.
The method ensures controlled breakage of the windshield, reducing the force needed to shatter the glass and minimizing injury risk by distributing stress uniformly and initiating cracking through the particles' sharp edges.
Smart Images
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Abstract
Description
[0001] The invention relates to a method for operating a motor vehicle, comprising safety glazing with a laminated glass windshield firmly connected to a body shell of the motor vehicle and having residual glass stress.
[0002] International Patent Application WO 2019 / 245 819 A1 discloses a glass laminate comprising an outer glass pane and an inner glass pane with a polymer interlayer between them, wherein one of the glass panes includes fracture initiation points in a predetermined pattern to weaken the glass laminate in the event of a predetermined external impact on the outer glass pane. European Patent EP 2 858 820 B1 discloses a laminated glass comprising an outer glass pane and an inner glass pane, the latter including weak points to weaken the laminated glass in the event of an internal impact. French Patent Application FR 2 129 880 A1 discloses a safety glazing comprising two glass panes bonded by a plastic film, wherein at least one of the glass panes includes a network of surface crack lines.German patent application DE 10 2006 028 484 A1 discloses a pedestrian impact protection device for a motor vehicle, consisting of a laminated glass windshield, an impact detection system, and a destructive device, wherein the destructive device, by means of the impact detection system, pre-damages the windshield before the impact of the person. German patent application DE 102 09 355 A1 discloses a safety device for a motor vehicle in which the windshield of the motor vehicle can be moved forward a certain distance relative to the A-pillars of the body by means of an actuator device, based on a corresponding trigger signal from an accident sensor, wherein the moving process is a pivoting process, and wherein the windshield is mounted so as to pivot relative to the body.German utility model DE 20 2011 101 348 U1 discloses a multi-walled window pane for a motor vehicle with two pane elements between which a cavity is formed, which is fluid-tightly encapsulated to the outside by means of a circumferential connecting web. German patent application DE 10 2014 215 788 A1 discloses a pedestrian protection device for a motor vehicle comprising a windshield, a front flap which, in the event of a collision or impending collision with a pedestrian, can be adjusted from a normal position to an up position by means of an adjustment device, and a windshield damage device, wherein the windshield damage device is designed such that adjusting the front flap to the up position causes immediate damage to the windshield.German patent application DE 10 2011 005 294 A1 discloses a safety device for a vehicle with a windshield damage device that can be automatically triggered to damage a vehicle windshield depending on at least one parameter. German patent application DE 10 2018 212 352 A1 discloses a windshield for a vehicle made of laminated safety glass with an outer glass layer and an inner glass layer and an intermediate plastic film, as well as at least one predetermined breaking point, wherein the at least one predetermined breaking point is equipped to be actively triggered to shatter the windshield and the triggering means acting on the predetermined breaking point are arranged in the windshield itself.
[0003] The object of the invention is to further increase the safety in the operation of a motor vehicle which comprises safety glazing with a windshield made of laminated glass with residual glass stress, which is firmly connected to a body shell of the motor vehicle.
[0004] The problem is solved by a method with the features of claim 1. The windshield, for example, is bonded to vehicle-mounted body components using a suitable windshield adhesive. The windshield is typically fixed to a roof rail at the top. At the bottom, the windshield is typically fixed to a cowl frame. At its sides, the windshield is typically fixed to the A-pillars. The laminated glass of the windshield comprises an interlayer with cavities that form carrier bubbles within the laminated glass, filled with a fluid loaded with particles. The cavities can advantageously be introduced into the interlayer during the manufacturing process. During the manufacturing process or in an additional process step, the particles can then be introduced into the cavities along with the fluid, in particular a suitable gas or liquid.The cavity filled with fluid is called a carrier bubble. The particles typically range in size from micrometers to a maximum of millimeters. The cavities in which the particles are arranged are significantly larger than the particles themselves, allowing them to move freely within the carrier bubbles. Upon intrusion through an outer pane, the carrier bubbles rupture, releasing the fluid in the intermediate film and initiating the desired cracking process within an inner pane. Under normal operating conditions, the particles can move freely within the carrier bubble. Upon a head impact, the outer pane is deformed. The intrusion of the outer pane then exerts pressure on the carrier bubbles in the intermediate film, causing them to increase in pressure and collapse.The fluid is released, and capillary action distributes some of the liquid and particles between the two discs. The particles in the carrier bladder are advantageously designed with sharp edges that, upon further intrusion of the head, initiate cracking in the inner disc. This allows the force required to break the disc to be reduced in a controlled manner.
[0005] Further advantages, features, and details of the invention will become apparent from the following description, in which various exemplary embodiments are described in detail with reference to the drawing. The drawing shows: Fig. 1 a perspective view of part of a motor vehicle with a windshield attached to a body shell; Fig. 2 a mechanical actuator, which is not the subject of the claimed invention, with a translationally movable actuator element that engages an upper edge region of the windshield, in longitudinal section; Fig. 3. A section through three fastening sections of a windshield to an A-pillar, in which the windshield is attached to the A-pillar with varying degrees of force; Fig. 4 the same representation as in Fig. 3 after activation of the mechanical actuator with the actuator element; Fig. 5. A representation of a section through a laminated glass windshield with an intermediate film arranged between an inner pane and an outer pane, wherein cavities are formed in the intermediate film which are filled with a fluid loaded with particles; Fig. 6 the windshield Fig. 5 in a head impact; and Fig. 7 the windshield from the Fig. 5 and Fig. 6 in the case of defined breaking due to head impact.
[0006] In Fig. Figure 1 shows the body shell 2 of a motor vehicle 1 in perspective. The body shell 2 comprises a cowl frame 3, two A-pillars 4, 5 and a roof rail 6. A windshield 7 is attached to the body shell 2 of the motor vehicle 1, for example by a conventional adhesive bond.
[0007] The windshield 7 comprises a laminated glass 8. The laminated glass 8 serves to represent safety glazing 9 on the body shell 2 of the motor vehicle 1.
[0008] In Fig. Figure 2 shows that a safety system 10 with a mechanical actuator 11 is integrated into the roof rail 6 of the motor vehicle 1. The mechanical actuator 11 comprises an actuator element 12, which is designed as a slide.
[0009] The actuator element 12 is guided in a guide 13 so that it can move translationally back and forth. Fig. Figure 2 shows the actuator element 12 in a rest position. Upon appropriate activation of the mechanical actuator 11, the actuator element 12 can be extended from its rest position in a forward direction 14, indicated by an arrow.
[0010] The windshield 7 is attached to the actuator element 12 by a bead of adhesive 15. When the actuator element 12 is extended in the forward direction 14, a bending moment is introduced into the windshield 7. This bending moment leads to a significant increase in residual stress in the laminated glass from which the windshield 7 is formed.
[0011] In Fig. Figure 3 shows how the windshield 7 is attached to the A-pillar 5 of the vehicle body shell. The windshield 7 is attached to the A-pillar 5 with varying degrees of force in three fastening sections 17, 18, 19 along the A-pillar 5. An arrow 16 indicates Fig. Figure 3 indicates how, with the actuator element 12, a force is applied to the upper area of the windshield 7 when the mechanical actuator is activated.
[0012] In fastening sections 17, 18, and 19, the windshield 7 is bonded to the A-pillar 5, for example, using different adhesives with varying mechanical properties. Isotropic strengths exist within fastening sections 17, 18, and 19. However, since a separate adhesive is used for each fastening section 17, 18, and 19, the adhesive and cohesive forces differ between these sections.
[0013] In the fastening section 17, which is located closest to the actuator element 12, a low-strength adhesive is advantageously used. This ensures that the windshield 7 can detach from the A-pillar 5 in the fastening section 17 when the force 16 is applied.
[0014] The higher strengths in the underlying fastening sections 18, 19 result in an inhomogeneous stress distribution in the windshield 7, which, as can be seen in Fig. As can be seen in Figure 4, a bend or a break can be induced along a bending edge 20. The bend or break in the windshield 7 can be controlled by varying the dimensions of the fastening sections 17, 18, 19 and the adhesives used.
[0015] In the Fig. 5, Fig. 6 to Fig. Figure 7 shows that the windshield 7 can advantageously be formed from laminated glass 8 with a special interlayer 22. The interlayer 22 is arranged between an inner pane 21 and an outer pane 23 of the windshield 7. Cavities 24 are formed in the interlayer 22. The cavities 24 are filled with a fluid 25. The fluid 25 is loaded with particles 26.
[0016] The cavity 24 filled with fluid 25 is referred to as the carrier bladder 29. In the Fig. 6 and Fig. Figure 7 illustrates what happens when an object 27, in particular a head in a pedestrian accident, hits the windshield 7.
[0017] In Fig. Figure 6 shows that the outer pane 23 is deformed by the impact. Fig. Figure 7 illustrates how the outer disk 23, through its intrusion, presses on the carrier bubbles 29 in the intermediate film 22. Due to the associated pressure increase, the carrier bubbles 29 collapse and burst, as shown in Figure 7. Fig. 7 is indicated by symbol 28.
[0018] The fluid contained in the carrier bladders 29 is released. Capillary forces distribute some of the fluid 25 and particles 26 between the disks 21 and 23. The particles 26 in the carrier bladder 29 are designed with sharp edges which, upon further intrusion of the object 27, initiate cracking in the inner disk 21. Reference sign 1 motor vehicle 2 Shell construction 3 Windshield frames 4 A-pillar 5 A-pillar 6 roof beam 7 Windscreen 8 laminated glass 9 Safety glazing 10 Security system 11 mechanical actuators 12 actuator elements 13 Leadership 14 Forward direction 15 glue beads 16 force 17 Fastening section 18 Fastening section 19 Fastening section 20 Bending edge 21 inner disc 22 Intermediate slide 23 Outer pane 24 cavity 25 Fluid 26 particles 27 Subject 28 Symbol 29 Carrier bladder
Claims
[1] Method for operating a motor vehicle (1) with a safety system (10) wherein the motor vehicle (1) comprises safety glazing (9) with a windshield (7) made of laminated glass (8) with residual glass stress, which is firmly connected to a body shell (2) of the motor vehicle (1), characterized bythat the laminated glass (8) of the windshield (7) comprises an intermediate film (22) with cavities (24) which, in the laminated glass (8), constitute carrier bubbles (29) filled with a fluid (25) loaded with particles (26), wherein the carrier bubbles (29) burst upon intrusion through an outer pane (23), releasing the fluid (25) in the intermediate film (22) and the particles (26) initiating desired cracking in an inner pane (21), wherein the outer pane (23) is deformed by the head impact, wherein the outer pane (23), through its intrusion, presses on the carrier bubbles (29) in the intermediate film (22), thereby increasing the pressure in them and causing the carrier bubbles (29) to collapse, releasing the fluid (25), and wherein, through capillary action, some of the fluid (25) as well as particles (26) are dispersed between the two panes distribute, wherein the particles (26) in the carrier bubble (29) are designed,that they have sharp edges which, upon further intrusion of the head, initiate cracking in the inner disk (21).