JP7026088B2 - Collision energy absorbing parts for automobiles - Google Patents

Description

The present invention relates to an automobile collision energy absorbing component, and more particularly to an automobile collision energy absorbing component that absorbs collision energy by crushing the shaft in the longitudinal direction when a collision load is input from the front or the rear of the vehicle body.

There are many technologies for optimizing the shape, structure, materials, etc. of automobile parts as technologies for improving the collision energy absorption performance of automobiles. Furthermore, in recent years, many technologies have been proposed in which a resin (foamed resin, etc.) is foamed and filled inside an automobile part having a closed cross-sectional structure to improve the collision energy absorption performance of the automobile part and reduce the weight. Has been done.

For example, Patent Document 1 describes a structural member for an automobile having a structure in which a closed space is formed inside by aligning the top plate directions of hat cross-sectional parts such as side sills, floor members, and pillars and overlapping flanges. Disclosed is a technique for improving the bending strength and torsional rigidity of the structural member for automobiles, and improving the rigidity and collision safety of the vehicle body by filling with the above.

Further, in Patent Document 2, when a high-rigidity foam is filled in an internal space of a closed cross-section structure such as a pillar in which a hat cross-section component is opposed to each other and a flange portion is aligned, the high-rigidity foam is filled and foamed. A technique for fixing a foam by a compression reaction force to improve vibration isolation that suppresses transmission of vibration sound and improving strength, rigidity, and impact energy absorption is disclosed.

Japanese Unexamined Patent Publication No. 2006-240134 Japanese Unexamined Patent Publication No. 2000-318575

According to the techniques disclosed in Patent Document 1 and Patent Document 2, by filling the inside of an automobile part with a foam filler or a foam, the strength against bending deformation of the automobile part and the impact energy of bending deformation due to collision It is said that it is possible to improve the absorbency and the rigidity against torsional deformation, and it is possible to suppress the deformation of the automobile parts.
However, when a collision load is input from the front or the rear of the vehicle and the shaft is crushed, such as a front side member or a crash box, which is the object of the present invention, the vehicle buckles and deforms in a bellows shape to absorb the collision energy. For the parts, there is a problem that it is difficult to improve the absorption of collision energy even if the technique of filling the inside of the automobile parts with a foam filler or a foam is applied.

The present invention has been made to solve the above-mentioned problems, and when a collision load is input from the front or the rear of a vehicle body such as a front side member or a crash box to crush the shaft in a bellows shape. It is an object of the present invention to provide a collision energy absorbing component for an automobile capable of improving the collision energy absorbing effect.

(1) The automobile collision energy absorbing component according to the present invention is provided at the front or rear of the vehicle body, and when a collision load is input from the front or the rear of the vehicle body, the shaft is crushed to absorb the collision energy. Therefore, a tubular member having a tensile strength of 590 MPa class or more and 1180 MPa class or less, having a top plate portion and a pair of vertical wall portions following the top plate portion, and a steel plate having a lower tensile strength than the tubular member. It is formed from, and is arranged inside the tubular member so as to straddle the top plate portion, and both ends thereof are joined to the inner surface of the pair of vertical wall portions, and a part of the peripheral wall portion of the tubular member. It has a closed cross-section space forming wall member forming a closed cross-section space between the two, and a resin filled in the closed cross-section space, and the resin contains a rubber-modified epoxy resin and a curing agent. It is characterized by a tensile elongation at break of 80% or more, an adhesive strength between the tubular member and the closed cross-section space forming wall member of 12 MPa or more, and a compression nominal stress of 6 MPa or more at a compression nominal strain of 10%. be.

(2) The automobile collision energy absorbing component according to the present invention is provided at the front or rear of the vehicle body, and when a collision load is input from the front or the rear of the vehicle body, the shaft is crushed to absorb the collision energy. Therefore, a tubular member having a tensile strength of 590 MPa class or more and 1180 MPa class or less, having a top plate portion and a pair of vertical wall portions following the top plate portion, and a steel plate having a lower tensile strength than the tubular member. It is formed from, and is arranged inside the tubular member so as to straddle the top plate portion, and both ends thereof are joined to the inner surface of the pair of vertical wall portions, and a part of the peripheral wall portion of the tubular member. It has a closed cross-section space forming wall member forming a closed cross-section space between the two, and a resin filled in the closed cross-section space. It is characterized in that the adhesive strength between the tubular member and the closed cross-section space forming wall member is 12 MPa or more, and the compression nominal stress at 10% compression nominal strain is 6 MPa or more.

In the present invention, it is provided at the front or rear of the vehicle body, and when a collision load is input from the front or the rear of the vehicle body, the shaft is crushed to absorb the collision energy, and the tensile strength is 590 MPa class or more and 1180 MPa. The tubular member is formed of a steel plate of grade or lower, has a top plate portion and a pair of vertical wall portions following the top plate portion, and is formed of a steel plate having a lower tensile strength than the tubular member. A closed cross-section space forming wall member which is arranged inside the top plate portion so as to straddle the top plate portion and both ends thereof are joined to the inner surface of the pair of vertical wall portions to form a closed cross-section space between the tubular member and the tubular member. And the resin filled in the closed cross-sectional space, the resin contains a rubber-modified epoxy resin and a curing agent, or a rubber-modified epoxy resin, and has a tensile elongation at break of 80% or more, and the cylinder. Since the adhesive strength between the shaped member and the closed cross-section space forming wall member is 12 MPa or more and the nominal compressive stress at 10% compression nominal strain is 6 MPa or more, a collision load is input from the front or rear of the vehicle body and the shaft collapses. In this process, buckling deformation can be repeatedly generated in a bellows shape without reducing the deformation resistance of the tubular member, and the effect of absorbing collision energy can be improved.

It is explanatory drawing explaining the structure of the collision energy absorption component for automobiles which concerns on embodiment of this invention. It is sectional drawing of the collision energy absorption component for automobiles which concerns on this embodiment. It is a figure explaining the shaft crushing test method of the collision energy absorption component for automobiles in an Example. It is a figure which shows the structure of the test body used for the shaft crushing test in an Example (invention example). It is a figure explaining the method of measuring the adhesive strength in an Example. It is a figure which shows the structure of the test body used for the shaft crushing test in an Example (comparative example). It is a figure which shows the measurement result of the collision load and the shaft crush deformation amount (stroke) when the shaft crush test was performed using the collision energy absorption component for automobiles which concerns on a comparative example as a test body in an Example. It is a figure which shows the measurement result of the collision load and the shaft crush deformation amount (stroke) when the shaft crush test was performed using the collision energy absorption component for automobiles which concerns on the invention example as a test body in an Example.

The collision energy absorbing component for an automobile according to the embodiment of the present invention will be described below with reference to FIGS. 1 and 2. In the present specification and the drawings, elements having substantially the same function and configuration are designated by the same reference numerals, so that duplicate description will be omitted.

As shown in FIG. 1, the collision energy absorbing component 1 for an automobile according to the present embodiment has a tubular member 3 composed of an outer component 5 and an inner component 7, and is provided at the front or rear of the vehicle body. It absorbs collision energy when a collision load is input from the front or rear of the vehicle body, and forms a closed cross-sectional space with the outer component 5 which is a part of the peripheral wall portion of the tubular member 3. It includes a cross-section space forming wall member 9 and a resin 11 that fills the cross-section of the closed cross-section space.

<Cylindrical member>
The tubular member 3 has a top plate portion 5a and a pair of vertical wall portions 5b following the top plate portion 5a by crushing the shaft to absorb the collision energy. As shown in FIG. 2, the top plate portion 5a and the vertical wall portion 3 are provided. The flange portion 5c of the outer component 5 having a hat cross-sectional shape composed of the portions 5b and the flange portion 5c and the both end portions of the flat plate-shaped inner component 7 are joined to form a cylindrical shape.

The outer component 5 and the inner component 7 constituting the tubular member 3 are both made of steel plates having a tensile strength of 590 MPa class or more and 1180 MPa class or less. Here, examples of the types of steel sheets include cold-rolled steel sheets, hot-rolled steel sheets, galvanized steel sheets, galvanized steel sheets, and aluminum alloy-plated steel sheets.

The tubular member 3 has a closed cross section such as a front side member extending in the front-rear direction of the vehicle body at the left and right positions of the front portion of the vehicle body to form a part of the vehicle body skeleton, and a crash box provided at the front end or the rear end of the vehicle body skeleton. Used for automobile parts having a structure, the automobile parts are arranged on the vehicle body so that the axial direction (longitudinal direction) of the tubular member 3 coincides with the front-rear direction of the vehicle body.

<Closed cross-section space forming wall member>
The closed cross-section space forming wall member 9 is made of a steel plate having a lower tensile strength than the tubular member 3, and as shown in FIG. 2, the outer component 5 and the inner component 7 inside the tubular member 3 are formed. It is a member having a substantially U-shaped cross section arranged so as to straddle the top plate portion 5a between them, and both ends thereof are joined to a pair of vertical wall portions 5b of the outer component 5 to form a peripheral wall portion of the tubular member 3. A closed cross-sectional space is formed between the top plate portion 5a and the vertical wall portion 5b of the outer component 5, which is a part of the outer component 5.

Both ends of the closed cross-section space forming wall member 9 and the vertical wall portion 5b are joined by, for example, spot welding.
Further, the closed cross-sectional space formed between the closed cross-sectional space forming wall member 9 and the outer component 5 has a closed cross-sectional shape in a direction intersecting the axial direction of the cylindrical member 3 shown in FIG. It refers to a space in which the closed cross section is continuously formed along the axial direction of the tubular member 3.

<Resin>
The resin 11 is filled in the closed cross-section space formed between the closed cross-section space forming wall member 9 and the outer component 5.

The resin 11 contains a rubber-modified epoxy resin and a curing agent, and by being heat-treated at a predetermined temperature and time, the outer component 5 and the closed cross-sectional space forming wall member 9 are formed by the adhesive ability of the resin 11 itself. Can be adhered to.
Further, the resin 11 has physical properties such as a tensile elongation at break of 80% or more, an adhesive strength with the tubular member 3 and the closed cross-section space forming wall member 9 of 12 MPa or more, and a compression nominal stress of 6 MPa or more at a compression nominal strain of 10%. It is a thing. All of these physical properties are values after the resin 11 is heat-treated.

The tensile elongation at break, the adhesive strength, and the nominal compressive stress may be the values obtained by the following methods, respectively.

≪Tension fracture elongation≫
An uncured resin is placed between two steel plates adjusted to a predetermined gap, heat-cured under predetermined conditions, the steel plates are peeled off to produce a flat resin, and the flat resin is processed into a predetermined shape. To prepare a test piece. Next, a tensile test is performed at a predetermined tensile speed until the resin breaks, and the amount of elongation between marked lines at the time of resin breakage is measured. Then, the measured elongation between the marked lines at the time of resin break is divided by the initial distance between the marked lines, and the value displayed as a percentage is defined as the tensile elongation at break.

≪Adhesive strength≫
An uncured resin is placed between two steel plates adjusted to a predetermined gap and heat-cured under predetermined conditions to prepare a test piece. Next, the test piece is subjected to a tensile test at a predetermined tensile speed, and the load when the steel plate and the resin are broken is measured. Then, the value obtained by dividing the measured load at break by the bonding area between the steel sheet and the resin (= shear bonding strength) is defined as the bonding strength.

≪Compression nominal stress≫
An uncured resin is placed between two steel plates adjusted to a predetermined gap, heated and cured under predetermined conditions, and the steel plates are peeled off to prepare a flat resin. Next, the flat plate-shaped resin is cut out into a columnar shape to prepare a test piece. Then, the circular surface of the test piece is used as a compression surface, and the value obtained by dividing the load when compressed to a nominal strain of 10% at a predetermined test speed by the cross-sectional area of the initial test piece is subjected to the compression nominal stress.

The reason for defining the type and physical properties of the resin 11 in the collision energy absorbing component 1 for automobiles according to the present embodiment as described above is as follows.
First, since the resin 11 contains a rubber-modified epoxy resin and a curing agent, when a collision load is input to the tubular member 3 and the shaft is crushed and deformed in a bellows shape, the resin 11 is heat-cured by heat treatment. By adhering to the tubular member 3 and the closed cross-sectional space forming wall member 9 with an adhesive strength of 12 MPa or more, the resin 11 can be deformed following the deformation of the tubular member 3.

When the tensile fracture elongation is 80% or more, it is possible to prevent the resin 11 itself from breaking when the resin 11 is deformed following the axial crush deformation of the tubular member 3.

When the adhesive strength is 12 MPa or more, it is prevented that the resin 11 is separated from the cylindrical member 3 and the closed cross-section space forming wall member 9 in the axial crushing process of the tubular member 3 to reduce the buckling resistance and the deformation resistance. be able to.

When the nominal compressive stress at 10% of the nominal compressive strain is 6 MPa or more, even if the tubular member 3 is deformed into a bellows shape in the axial crushing process, the resin 11 itself has sufficient proof stress so as not to be crushed and broken. Can be done.

Then, the type and composition of the rubber-modified epoxy resin and the curing agent, and the temperature and time of the heat treatment may be appropriately adjusted so that the tensile elongation at break, the adhesive strength, and the nominal compressive stress of the resin 11 are within the above ranges.

The curing agents include polyamines (aliphatic polyamines, aromatic amines, aromatic polyamines, polyamide amines), acid anhydrides, phenols, thiols, and latent curing agents such as dicyandiamide, imidazole compounds, and ketimine. A curing agent optimally selected according to the usage environment, reaction temperature, etc., such as a compound and an organic acid hydrazide, is preferable.

As described above, in the collision energy absorbing component 1 for automobiles according to the present embodiment, in the process in which the collision load is input to the tubular member 3 and the shaft is crushed, the resin 11 is separated from the tubular member 3 and the closed cross-section space forming wall member 9. The buckling resistance can be improved without dissociation, and the tubular member 3 can be repeatedly buckled in a bellows shape without reducing the deformation resistance of the tubular member 3, improving the absorption of collision energy. Can be made to.

In the above description, the resin 11 contains a rubber-modified epoxy resin and a curing agent after being heat-treated. However, depending on the amount of the curing agent filled in the closed cross-section space formed between the closed cross-section space forming wall member 9 and the outer component 5, the curing agent may be added to the resin 11 after heat treatment at a predetermined temperature and time. It may not remain or may not be detected.

Therefore, as another aspect of the collision energy absorbing component 1 for automobiles according to the embodiment of the present invention, the resin 11 after the heat treatment does not contain a curing agent or is not detected, and is heat-treated at a predetermined temperature and time. By doing so, the outer component 5 and the closed cross-sectional space forming wall member 9 may be adhered to each other by the adhesive ability of the resin 11 itself.

Even when the resin 11 after heat treatment does not contain a curing agent or is not detected, its physical properties are such that the tensile elongation at break is 80% or more, and the resin 11 adheres to the tubular member 3 and the closed cross-section space forming wall member 9. It is assumed that the strength is 12 MPa or more and the nominal compressive stress at 10% of the nominal compressive strain is 6 MPa or more. Then, the type and composition of the rubber-modified epoxy resin and the curing agent to be filled in the closed cross-sectional space before the heat treatment so that the tensile elongation at break, the adhesive strength and the nominal compressive stress of the resin 11 are within the above ranges, and further, the heat treatment. The temperature and time may be adjusted as appropriate.

If the resin 11 containing the rubber-modified epoxy resin and containing no curing agent or not detected is within the range of the above physical properties, the resin 11 is tubular in the process of inputting a collision load to the tubular member 3 and crushing the shaft. The buckling resistance is improved without deviating from the member 3 and the closed cross-section space forming wall member 9, and further, the tubular member 3 is repeatedly buckled in a bellows shape without reducing the deformation resistance of the tubular member 3. It is possible to improve the absorption of collision energy.

An experiment for confirming the effect of the collision energy absorbing component for an automobile according to the present invention has been conducted, and the results will be described below.

In the experiment, a shaft crushing test is performed using the collision energy absorbing component for automobiles according to the present invention as a test body. In the shaft crushing test, as shown in FIG. 3, the test speed is 17.8 m / in the axial direction of the test body 31. Load-stroke showing the relationship between the load and the amount of shaft crush deformation (stroke) when the test piece length (axial length L ₀ of the test piece 31) is 80 mm from 200 mm to 120 mm by inputting the load with s. The curve was measured and the deformed state was photographed with a high-speed camera. Furthermore, from the measured load-stroke curve, the absorbed energy with a stroke of 0 to 80 mm was obtained.

FIG. 4 shows the structure and shape of the test body 31 as an example of the invention.
In the example of the invention, the collision energy absorbing component 1 for automobiles (FIGS. 1 and 2) according to the above-described embodiment of the present invention is used as a test body 31 and a shaft crush test is performed.
The test body 31 has a tubular member 3 in which the outer component 5 and the inner component 7 are joined by spot welding, and a closed cross-section space is formed between the outer component 5 and the closed cross-section space forming wall member 9. The entire region of the closed cross-section space is filled with the resin 11. The gap heights between the outer component 5 and the closed cross-section space forming wall member 9 are set to 1 mm, 3 mm, and 8 mm (FIGS. 4 (a) to 4 (c)).

A steel plate having a tensile strength of 590 MPa class to 1180 MPa class and a plate thickness of 1.2 mm or 1.4 mm was used for the outer component 5, and a steel plate having a tensile strength of 590 MPa class and a plate thickness of 1.2 mm was used for the inner component 7.
Further, as the closed cross-section space forming wall member 9, a steel plate having a tensile strength of 270 MPa class and a plate thickness of 0.5 mm was used.

The resin 11 is obtained by heat-treating a rubber-modified epoxy resin and a curing agent at a predetermined heating temperature and heating time, and the values of the tensile elongation at break, the adhesive strength, and the nominal compressive stress of the resin 11 after the heat treatment are set. It is within the scope of the present invention. Here, the tensile elongation at break, the adhesive strength, and the nominal compressive stress were obtained by separately performing the following test methods.

<Tension fracture elongation>
The gap between the two steel plates was adjusted to 2 mm, an uncured resin was placed between them, and the resin was heat-cured under the condition of holding at 180 ° C for 20 minutes, and the steel plates were peeled off to prepare a flat resin having a thickness of 2 mm. Subsequently, the flat plate-shaped resin is processed into a dumbbell shape (JIS No. 6 dumbbell) to prepare a test piece, and a tensile test is performed at a tensile speed of 2 mm / min until the resin breaks. Was measured. Then, the value obtained by dividing the measured amount of elongation between the marked lines at the time of resin break by the initial distance between the marked lines (= 20 mm) was displayed as a percentage, and was used as the tensile elongation at break.

<Shear adhesive strength>
As shown in FIG. 5, the adherend 23 and the adherend 25 are made of a steel plate (SPCC) having a width of 25 mm, a thickness of 1.6 mm, and a length of 100 mm, and are uncured on the bonded portion (width 25 mm, length 10 mm). The test piece 21 was obtained by heating and curing the resin 27 under the conditions of holding at 180 ° C. for 20 minutes in a state where the resin 27 was installed and adjusted to a thickness of 0.15 mm. Next, the test piece 21 was subjected to a tensile test at a tensile speed of 5 mm / min until the adherend 23 or the adherend 25 and the resin 27 broke, and the load at the time of breakage was measured. Then, the value obtained by dividing the load at the time of breaking by the area of the bonded portion (bonding area: width 25 mm × length 10 mm) was defined as the shear bonding strength.

<Compressive nominal stress>
The gap between the two steel plates was adjusted to 3 mm, an uncured resin was placed between them, and the product was heat-cured under the condition of holding at 180 ° C for 20 minutes, and the steel plates were peeled off to prepare a flat resin test piece with a thickness of 3 mm. .. Next, a cylindrical resin test piece having a diameter of 20 mm was cut out from the flat resin test piece and used as a test piece. Then, the circular surface with a diameter of 20 mm in the test piece is used as the compression surface, and the value obtained by dividing the load when compressed to a nominal strain of 10% at a test speed of 2 mm / min by the cross-sectional results of the initial test piece is the compression nominal stress. And said.

In this embodiment, as a comparison target, the case where the test body 33 (FIG. 6) having the same shape as the tubular member 3 and the closed cross-section space forming wall member 9 of the invention example and not filled with resin is used, and the invention. In a test body 31 having the same shape as the example, a case where the physical properties of the resin 11 were outside the range of the present invention was taken as a comparative example, and a shaft crush test was conducted in the same manner as in the invention example.
Table 1 shows the conditions of the structure of the test piece as an example of the invention and the comparative example, the type of resin, the tensile elongation at break, the adhesive strength, and the nominal compressive stress at 10% of the nominal compressive strain.

In Table 1, Invention Examples 1 to 7 show the tensile strength (590 MPa class or more and 1180 MPa class or less) of the steel plate used for the outer component 5 and the inner component 7 constituting the tubular member 3, and the closed cross-section space forming wall member 9. The tensile strength (270 MPa class) of the steel sheet used in the above, the type of the resin 11, the tensile elongation at break, the adhesive strength, and the nominal compressive stress are all within the scope of the present invention shown in the above-described embodiment. ..

In Invention Examples 1 to 4, the curing agent remains in the resin 11 after being heat-treated at a predetermined heating temperature and heating time. Further, in Invention Examples 5 to 7, the amount of the curing agent was smaller than that in Invention Examples 1 to 4, and the curing agent did not remain in the resin 11 after the heat treatment at a predetermined heating temperature and heating time. It was not detected.

On the other hand, in Comparative Examples 1 to 4, the test piece 33 not filled with the resin was used, and in Comparative Examples 5 to 7, the type of the resin 11 was epoxy or urethane, and the tensile elongation at break occurred. The test piece 31 in which at least one of the adhesive strength and the nominal compressive stress is outside the scope of the present invention is used.

7 and 8 show the measurement results of the load-stroke curve when the axial crush test was performed using the test body 33 according to Comparative Example 1 and the test body 31 according to Invention Example 1, respectively.
7 and 8 are load-stroke curves in which the horizontal axis is the stroke (mm) representing the amount of deformation of the test piece in the axial direction from the start of the collision, and the vertical axis is the load (kN) input to the test piece. The absorbed energy shown in the graph is the amount of collision energy absorbed when the stroke is 0 to 80 mm.

Comparative Example 1 shown in FIG. 7 is the result of the test body 33 (FIG. 6) not filled with resin, and the load input to the test body 33 shows a maximum value (about 300 kN) immediately after the start of input, and then. , The value of the load fluctuated with the buckling of the peripheral wall portion of the tubular member 3. The absorbed energy at the end of the test when the stroke reached 80 mm was 6.5 kJ.

In Invention Example 1 shown in FIG. 8, the resin 11 is filled in the closed cross-section space formed between the outer component 5 and the closed cross-section space forming wall member 9, and the tensile elongation at break (= 80%) and the adhesive strength (=). Both 12MPa) and the compression nominal stress (= 6MPa) at 10% compression nominal strain are the result of the test piece 31 which is within the scope of the present invention. From the load-stroke curve shown in FIG. 8, the maximum load immediately after the start of load input was about 400 kN, which was significantly improved as compared with Comparative Example 1 described above. Further, the deformation load when the stroke was 10 mm or later remained stable and high as compared with Comparative Example 1. The absorbed energy at a stroke of 0 to 80 mm was also significantly improved as compared with Comparative Example 1 to 13.1 kJ.

As described above, in the first invention example, the resin 11 is filled between the outer component 5 and the closed cross-section space forming wall member 9, and the tensile elongation at break, the proof stress, and the nominal compressive stress thereof are within the scope of the present invention. As a result, it can be seen that the buckling strength increases in the shaft crushing process, the deformation resistance increases without the resin 11 peeling off, and bellows-like compression deformation occurs, and the absorption of collision energy is improved.

Next, the shaft crushing test was performed by changing the structure of the test piece used for the shaft crushing test, the type of resin, and the adhesive strength, and the measurement results of the absorbed energy and the weight of the test piece at a stroke of 0 to 80 mm are shown in Table 1 above. show.

The weight of the test piece in Table 1 is the sum of the weights of the outer part 5, the inner part 7, the closed cross-section space forming wall member 9 and the resin 11 in the test body 31 filled with the resin 11. On the other hand, in the test body 33 not filled with resin, it is the total weight of each of the outer component 5, the inner component 7, and the closed cross-section space forming wall member 9.

As shown in FIG. 8 described above, the absorbed energy in Invention Example 1 was 13.1 kJ, which was significantly improved as compared with the absorbed energy of 6.5 kJ in Comparative Example 1. Further, even when compared with the absorption energy (= 8.5kJ) in Comparative Example 4 in which a steel plate (1180MPa class) having a higher tensile strength than Comparative Example 1 is used for the outer component 5, the absorption energy is significantly higher in Invention Example 1. Improved.

The test piece weight in Invention Example 1 was 1.28 kg, which was larger than the test piece weight (= 1.06 kg) in Comparative Example 1 not filled with resin. However, in Invention Example 1, the absorbed energy per unit weight obtained by dividing the absorbed energy by the weight of the test piece was 10.2 kJ / kg, which was higher than that of Comparative Example 1 (= 6.1 kJ / kg).

Invention Example 2 uses a test body 31 (FIG. 4 (c)) in which the thickness of the resin 11 is 1 mm, which is smaller than that of Invention Example 1.
The absorption energy in Invention Example 2 was 9.8 kJ, which was significantly improved as compared with Comparative Example 1 (= 6.5 kJ).
The weight of the test piece in Invention Example 2 was 1.12 kg, which was lighter than that of Invention Example 1. The absorbed energy per unit weight in Invention Example 2 was 8.5 kJ / kg, which was higher than that of Comparative Example 1 (= 6.1 kJ / kg).

In the third invention example, the test piece 31 (FIG. 4 (c)) having a tensile strength of 1180 MPa class and a thickness of the resin 11 of 1 mm of the steel plate used for the outer component 5 is used.
The absorption energy in Invention Example 3 was 12.6 kJ, which was significantly improved as compared with Comparative Example 4 (= 8.5 kJ).
The weight of the test piece in Invention Example 3 was 1.13 kg, which was lighter than that of Invention Example 1. Moreover, the absorbed energy per unit weight in Invention Example 3 was 11.2 kJ / kg, which was higher than that of Comparative Example 4 (= 7.9 kJ / kg).

In the fourth aspect of the invention, the test piece 31 (FIG. 4 (b)) having a tensile strength of 590 MPa class and a thickness of the resin 11 of 3 mm of the steel plate used for the outer component 5 is used.
The absorption energy in Invention Example 4 was 10.1 kJ, which was significantly improved as compared with Comparative Example 1 (= 6.5 kJ).
The weight of the test piece in Invention Example 4 was 1.19 kg, which was lighter than that of Invention Example 1. The absorbed energy per unit weight in Invention Example 4 was 8.5 kJ / kg, which was higher than that of Comparative Example 1 (= 6.1 kJ / kg).

In the fifth aspect of the invention, the test piece 31 (FIG. 4A) having a tensile strength of 590 MPa class and a thickness of the resin 11 of 8 mm of the steel plate used for the outer component 5 is used.
The absorbed energy in Invention Example 5 was 13.1 kJ, which was significantly improved as compared with the absorbed energy of 6.5 kJ in Comparative Example 1. Further, even when compared with the absorption energy (= 8.5kJ) in Comparative Example 4 in which a steel plate (1180MPa class) having a higher tensile strength than Comparative Example 1 is used for the outer component 5, the absorption energy is significantly higher in Invention Example 5. Improved.

In the sixth aspect of the invention, the test piece 31 (FIG. 4 (c)) having a tensile strength of 1180 MPa class and a thickness of the resin 11 of 1 mm of the steel plate used for the outer component 5 is used.
The absorbed energy in Invention Example 6 was 12.6 kJ, which was significantly improved as compared with Comparative Example 4 (= 8.5 kJ).
The weight of the test piece in Invention Example 6 was 1.12 kg, which was lighter than that of Invention Example 1. Moreover, the absorbed energy per unit weight in Invention Example 6 was 11.2 kJ / kg, which was higher than that of Comparative Example 4 (= 7.9 kJ / kg).

Inventive Example 7 uses a test piece 31 (FIG. 4 (b)) having a tensile strength of 590 MPa class and a thickness of resin 11 of 3 mm of the steel plate used for the outer component 5.
The absorption energy in Invention Example 7 was 10.1 kJ, which was significantly improved as compared with Comparative Example 1 (= 6.5 kJ).
The weight of the test piece in Invention Example 7 was 1.19 kg, which was lighter than that of Invention Example 1. The absorbed energy per unit weight in Invention Example 7 was 8.5 kJ / kg, which was higher than that of Comparative Example 1 (= 6.1 kJ / kg).

In Comparative Example 1, a test piece 33 (FIG. 6) not filled with resin was used, and the weight of the test piece was 1.06 kg. The absorbed energy was 6.5 kJ as shown in FIG. 7, and the absorbed energy per unit weight was 6.1 kJ / kg.

In Comparative Example 2, in the test body 33 having the same shape as that of Comparative Example 1, a steel plate having a plate thickness of 1.4 mm was used for the outer component 5, and the weight of the test body was 1.17 kg.
The absorbed energy in Comparative Example 2 was 7.0 kJ, and the absorbed energy per unit weight was 6.0 kJ / kg. Although the absorbed energy was higher than that of Comparative Example 1, it was not as good as that of Invention Examples 1 to 7.

In Comparative Example 3, in the test body 33 having the same shape as that of Comparative Example 1, a steel plate having a tensile strength of 980 MPa was used for the outer component 5, and the weight of the test body was 1.06 kg.
The absorbed energy in Comparative Example 3 was 8.1 kJ and the absorbed energy per unit weight was 7.6 kJ / kg, both of which were higher than those of Comparative Example 1 but not as high as those of Invention Examples 1 to 7.

In Comparative Example 4, in the test body 33 having the same shape as that of Comparative Example 1, a steel plate having a tensile strength of 1180 MPa was used for the outer component 5, and the weight of the test body was 1.07 kg.
The absorbed energy in Comparative Example 4 was 8.5 kJ and the absorbed energy per unit weight was 7.9 kJ / kg, both of which were higher than those of Comparative Example 1 but not as high as those of Invention Examples 1 to 7.

Comparative Example 5, Comparative Example 6 and Comparative Example 7 have the same shape as the test body 31 according to Invention Example 2, but at least one of the type of resin, the tensile elongation at break of the resin, the adhesive strength and the nominal compressive stress. One is a test body 31 (FIG. 4) which is outside the scope of the present invention.
The absorbed energy and the absorbed energy per unit weight in Comparative Example 5, Comparative Example 6 and Comparative Example 7 did not reach any of Invention Examples 1 to 7.

As described above, it has been shown that the collision energy absorbing component for automobiles according to the present invention can improve the collision energy absorption performance when a collision load is input in the axial direction and the shaft is crushed.

1 Collision energy absorbing parts for automobiles 3 Cylindrical parts 5 Outer parts 5a Top plate part 5b Vertical wall part 5c Flange part 7 Inner parts 9 Closed cross-section space forming wall member 11 Resin 21 Test piece 23 Adhesive body 25 Adhesive body 27 Resin 31 Specimen 33 Specimen

Claims (2)

A collision energy absorbing component for automobiles that is provided at the front or rear of a vehicle body and absorbs collision energy by crushing the shaft when a collision load is input from the front or rear of the vehicle body.
A cylindrical member made of steel plate with a tensile strength of 590 MPa class or more and 1180 MPa class or less, having a top plate part and a pair of vertical wall parts following it, and repeatedly buckling in a bellows shape .
It is a member having a substantially U-shaped cross-sectional shape, which is formed of a steel plate having a lower tensile strength than the tubular member and is arranged inside the tubular member so as to straddle the top plate portion, and both ends thereof. With a closed cross-section space forming wall member which is joined to the inner surface of the pair of vertical wall portions and forms a closed cross-section space between the top plate portion and the vertical wall portion which are a part of the peripheral wall portion of the tubular member. ,
With the resin filled in the closed cross-section space,
The resin comprises a rubber-modified epoxy resin and a curing agent.
For automobiles, the tensile elongation at break is 80% or more, the adhesive strength between the tubular member and the closed cross-section space forming wall member is 12 MPa or more, and the compression nominal stress at 10% compression nominal strain is 6 MPa or more. Collision energy absorbing parts. A collision energy absorbing component for automobiles that is provided at the front or rear of a vehicle body and absorbs collision energy by crushing the shaft when a collision load is input from the front or rear of the vehicle body.
A cylindrical member made of steel plate with a tensile strength of 590 MPa class or more and 1180 MPa class or less, having a top plate part and a pair of vertical wall parts following it, and repeatedly buckling in a bellows shape .
It is a member having a substantially U-shaped cross-sectional shape, which is formed of a steel plate having a lower tensile strength than the tubular member and is arranged inside the tubular member so as to straddle the top plate portion, and both ends thereof. With a closed cross-section space forming wall member which is joined to the inner surface of the pair of vertical wall portions and forms a closed cross-section space between the top plate portion and the vertical wall portion which are a part of the peripheral wall portion of the tubular member. ,
With the resin filled in the closed cross-section space,
The resin comprises a rubber-modified epoxy resin.
For automobiles, the tensile elongation at break is 80% or more, the adhesive strength between the tubular member and the closed cross-section space forming wall member is 12 MPa or more, and the compression nominal stress at 10% compression nominal strain is 6 MPa or more. Collision energy absorbing parts.

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