Head model for helmet protection performance test

Abstract

The invention discloses a head model for testing protective performance of a helmet, which is composed of a head model base and two sets of aluminum column modules arranged at the upper part of the head model base, and the aluminum column modules comprise two sets of aluminum column modules with different heights; the head die base consists of an upper part and a lower part which are positioned through an arc-shaped slide rail and a bolt; the lower part of the head mold base is fixed, and the pitching angle of the head mold is adjusted by sliding the upper part of the head mold base; a head mold chin structure is arranged at the upper part of the head mold base and is used for fixing a chin strap of the bulletproof helmet; positioning holes are formed in the two sides of the upper portion of the head mold base and used for positioning a special setting mold for daub. The bullet mark height of the bulletproof helmet generating large deformation under the impact effect can be accurately tested, the front portion, the rear portion, the left side, the right side and the top of the bulletproof helmet can achieve the same effect, and the problem that a traditional mold is not suitable for impact large-deformation bulletproof helmets is solved.

Description

Technical Field

[0001] The invention relates to the technical field of helmet protection performance testing, and in particular to a head model for helmet protection performance testing. Background Art

[0002] A bulletproof helmet is a piece of protective equipment used to protect the heads of soldiers, public security officers, etc. from bullets, fragments and other sharp objects. It has strong protective capabilities. At present, military or police bulletproof helmets are mostly made of high-strength composite materials, such as aramid fiber, ultra-high molecular weight polyethylene, etc.

[0003] A helmet model (hereinafter referred to as a head model) is often needed in the protective performance test of bulletproof helmets. There are four aluminum columns on the top of the head model, and its outer contour is designed according to the standard adult head and face size. When conducting a helmet protective performance test, fill the middle of the aluminum column with clay, then put the helmet to be tested on the head model filled with clay, tighten the chin strap, and then conduct ballistic tests on the front, back, left, right and top of the helmet respectively, and the impact point is located at the corresponding position of the clay. For example, the bulletproof helmet standard formulated by the American Institute of Justice (NIJ standard 0106.01), the safety technical performance requirements for military bulletproof helmets in my country (GJB 5115A-2012) and the police bulletproof helmets and masks (GA293-2012) all have relevant regulations and requirements. At the same time, the standard has clear requirements on the bullet hole height of bulletproof helmets under the impact of bullets or fragments. Based on this, the pit depth of the clay inside the head mold is used to evaluate the maximum deformation of the helmet during the impact process. When the bullet hole height is small, the pit depth of the clay can better reflect the bullet hole height of the helmet. As the bullet hole height increases, the deformation area of ​​the helmet increases accordingly. The four aluminum columns in the traditional head mold will inevitably affect the test results. When conducting research on the application of new materials in helmets, traditional head molds can no longer meet testing requirements. For example, new ultra-high molecular weight polyethylene fiber composite helmets currently still have problems such as excessive deformation. When conducting ballistic performance tests, the actual deformation width of some helmet samples is greater than the gap width between the aluminum columns of the head mold. At this time, the aluminum columns exert additional local constraints on the helmet body, thereby affecting the accuracy of the test results.

[0004] Therefore, the present invention designs a modular head model for testing the protective performance of helmets, and designs a special shaping mold for clay, which can more accurately test the real protective performance and bullet mark height of bulletproof helmets when they are greatly deformed by impact compared with traditional head models. Summary of the invention

[0005] The purpose of the present invention is to provide a head model for testing the protective performance of a helmet, which can accurately test the bullet hole height of a helmet that produces a large deformation under an impact, and the front, rear, left side, right side and top of the bulletproof helmet can all achieve the same effect, thereby solving the problem of the inapplicability of traditional molds to bulletproof helmets that produce a large deformation under impact.

[0006] The technical solution to achieve the purpose of the present invention is: a head model for testing the protective performance of a helmet, which is composed of a head model base and an aluminum column module arranged on the upper part of the head model base, wherein the aluminum column module includes two sets of aluminum column modules with different heights;

[0007] The head mold base is composed of an upper and lower part, which are positioned by an arc-shaped slide rail and bolts; the lower part of the head mold base is fixed, and the pitch angle of the head mold is adjusted by sliding the upper part of the head mold base; circular through holes are provided on both sides of the slide rail of the lower part of the head mold base, and a waist-shaped through hole is provided on the slide rail of the upper part of the head mold base, which is used to fix the relative posture between the upper part of the head mold base and the lower part of the head mold base;

[0008] The upper part of the headform base is provided with a headform chin structure for fixing the chin strap of the bulletproof helmet;

[0009] Positioning holes are arranged on both sides of the upper part of the head mold base for positioning the special shaping mold for the cement;

[0010] There are two sets of aluminum column modules, each set consists of four aluminum columns with similar structures, and the difference between the two sets of aluminum column modules is the height difference; a platform is arranged at the bottom of each aluminum column, and the platform is fixedly connected to the upper part of the head mold base.

[0011] Furthermore, the top surface of the head mold base is provided with four threaded holes, the bottom platform of the aluminum column is provided with a circular through hole, and the upper part of the head mold base is fixedly connected with the bottom platform of the aluminum column by bolts.

[0012] Furthermore, the fastening bolts pass through the circular through holes on both sides of the lower slide rail of the head mold base and the waist-shaped through holes on the upper slide rail of the head mold base, and are tightened with nuts to fix the relative posture between the upper part of the head mold base and the lower part of the head mold base.

[0013] Furthermore, the lower part of the head mold base is provided with four circular through holes at the bottom, which are fixed to the corresponding target frame in the test site by bolts.

[0014] Furthermore, it is necessary to select the number and installation positions of the aluminum columns according to the impact position of the next bullet-proof helmet test. If the next test is the front of the bullet-proof helmet, two aluminum columns are installed at the rear of the head mold. If the next test is the rear of the bullet-proof helmet, two aluminum columns are installed at the front of the head mold. If the next test is the left side of the bullet-proof helmet, two aluminum columns are installed on the right side of the head mold. If the next test is the right side of the bullet-proof helmet, two aluminum columns are installed on the left side of the head mold. If the next test is the top of the bullet-proof helmet, a set of aluminum columns with a lower height is installed.

[0015] Furthermore, the head model also includes a special shaping mold for cement, which is installed on the upper part of the head model base.

[0016] Furthermore, the main body of the special shaping mold for cement is an ellipsoidal shell whose inner wall is completely fitted with the outer surface of the aluminum column module and is spliced ​​into an ellipsoidal cylinder shell. The top of the mold is open for filling the inside with cement.

[0017] Furthermore, waist-shaped holes are arranged on both sides of the special shaping mold for the clay, and cylindrical pins pass through the waist-shaped holes and the positioning holes on the upper part of the head mold base in sequence.

[0018] Compared with the prior art, the present invention has the following beneficial effects:

[0019] (1) The head mold proposed in the present invention adopts a modular design, including a head mold base and an aluminum column module. The corresponding aluminum column can be installed / disassembled according to the bullet-proof helmet's impact position, so as to achieve the purpose of accurately measuring the bullet mark height of the bullet-proof helmet;

[0020] (2) In the present invention, a set of aluminum column modules with a relatively low height is designed for the bullet impact test scenario on the top of the bulletproof helmet, which can achieve the purpose of accurately measuring the height of the bullet mark on the top of the bulletproof helmet;

[0021] (3) The head mold base of the present invention is composed of an upper part of the head mold base and a lower part of the head mold base. The two are positioned by an arc-shaped slide rail and bolts, so that the pitch adjustment of the tested bulletproof helmet can be realized, which is convenient for adjusting the impact angle of bullets / fragments on the bulletproof helmet. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Schematic diagram of the appearance of a modular head mold according to an embodiment of the present invention.

[0023] Figure 2 Schematic diagram of a head mold base according to an embodiment of the present invention.

[0024] Figure 3 Schematic diagram of the lower part of the headform base.

[0025] Figure 4 Schematic diagram of the upper part of the headform base.

[0026] Figure 5Two groups of aluminum column modules with different heights according to an embodiment of the present invention.

[0027] Figure 6 The present invention provides a special shaping mold for the cement according to the embodiment of the present invention. DETAILED DESCRIPTION

[0028] Combination Figure 1 , Figure 6 A modular head mold is composed of a head mold base 2 and an aluminum column module 1 arranged above the head mold base 2, and a special shaping mold 14 for cement is also provided.

[0029] Combination Figure 2 , Figure 3 , Figure 4 , the head mold base is composed of two parts, the upper and lower parts, which are positioned by an arc-shaped slide rail 5. The bottom end of the lower part 4 of the head mold base is a platform structure, on which four vertical through holes 7 are arranged, and the positions of the through holes 7 correspond to the corresponding holes on the corresponding target frame in the test site when in use, and can be fixed to the corresponding target frame in the test site by bolts. When the lower part 4 of the head mold base is fixed, the purpose of adjusting the pitch angle of the head mold can be achieved by sliding the upper part 3 of the head mold base. The lower part 4 of the head mold base is provided with circular through holes 6 on both sides of the arc-shaped slide rail 5, and the upper part 3 of the head mold base is provided with a waist-shaped through hole 10. The fastening bolts pass through the circular through holes 6, the waist-shaped through holes 10, and the circular through holes 6 in sequence and are tightened with nuts to achieve the purpose of fixing the relative posture between the upper part 3 of the head mold base and the lower part 4 of the head mold base. The top surface of the upper part 3 of the head mold base is provided with four threaded holes 8. The head mold base 2 is provided with a head mold chin 9 structure for fixing the chin strap of the bulletproof helmet. Positioning holes 11 are provided on both sides of the upper part of the head mold base for fixing the special shaping mold 13 for the cement.

[0030] Combination Figure 1 , Figure 5 There are two sets of aluminum column modules, each set is composed of four aluminum columns 12 of similar structure, and the difference between the two sets of aluminum column modules is the height. A platform is set at the bottom of each aluminum column 12, and a circular through hole 13 is set on the platform. The aluminum column is fixed to the threaded hole 8 at the top of the upper part 3 of the head mold base by bolts.

[0031] Combination Figure 6 The main body of the special shaping mold 14 for glue is a semi-ellipsoidal shell whose inner wall is completely fitted with the outer surface of the aluminum column module 12, and an ellipsoidal shell of a certain height is spliced ​​below. The top of the mold 14 is open for filling glue inside. A waist-shaped hole 15 is provided on both sides of the ellipsoidal column. The cylindrical pin can pass through the waist-shaped hole 14 and be inserted into the head mold (upper) positioning hole 15 to limit the longitudinal displacement of the mold during the process of filling glue.

[0032] Example

[0033] The following will combine the drawings in the embodiments of the present invention to clearly and completely explain the scheme in the embodiments of the present invention.

[0034] Reference Figure 1-Figure 6 A head model for testing the protective performance of a helmet is composed of a head model base 2 and an aluminum column module 1 arranged on the upper part of the head model base, the two can be connected by bolts, and a special shaping mold 14 for clay is also provided.

[0035] Combination Figure 1-Figure 4 Before the experiment, bolts of suitable size are used to pass through the circular through holes 7 on the platform of the lower part 4 of the head mold base to fix it on the corresponding target frame in the test site, and then the upper part 3 of the head mold base is installed on the lower part 4 of the head mold base through the arc guide rail, and bolts are used to pass through the circular through holes 6, waist-shaped through holes 10, and circular through holes 6 in sequence and then tightened with nuts to pre-fix the relative positions of the lower part 4 of the head mold base and the upper part 3 of the head mold base. After the sample is fixed, the pitch angle of the upper part 3 of the head mold base can be adjusted after loosening the bolts. Use bolts to pass through the circular through holes 13 on the bottom platform of the aluminum column 12 and screw into the threaded holes 8 on the top of the upper part 3 of the head mold base to fix the aluminum column 12 on the top of the upper part of the head mold base. It is necessary to select the quantity and installation position of aluminum column 12 according to the bullet striking position of the next experiment of bulletproof helmet, if the front of the next test bulletproof helmet, two aluminum columns at the rear of the head mold are installed, if the rear of the next test bulletproof helmet, two aluminum columns at the front of the head mold are installed, if the left side of the next test bulletproof helmet, two aluminum columns on the right side of the head mold are installed, if the right side of the next test bulletproof helmet, two aluminum columns on the left side of the head mold are installed, if the top of the next test bulletproof helmet, a set of (four in total) aluminum columns with low height is installed. The special shaping mold 14 of the described cement is installed on the upper part 3 of the head mold base, and the cylindrical pins are successively passed through the waist-shaped holes 15 in the shaping mold 14 and the positioning holes 11 in the upper part 3 of the head mold base, and the left and right sides of the shaping mold 14 are all inserted with cylindrical pins. The testing cement is filled into the space between the inner wall of the shaping mold 14 and the aluminum column 12 through the top opening of the shaping mold 14, ensuring that the cement texture is uniform, there is no gap, no cavity inside, and the surface is smooth. Then, remove the cylindrical pin and the forming mold, fix the test helmet sample on the head mold, fasten the chin strap of the bulletproof helmet at the chin of the head mold, tighten the strap until the rear lower edge of the bulletproof helmet coincides with the rear lower edge of the head mold, and use a special tensioning device to pull the bulletproof helmet upwards to meet the specified tensioning force requirements.

Claims

1. A head model for testing the protective performance of a helmet, characterized in that: It is composed of a head mold base (2) and an aluminum column module (1) arranged on the upper part of the head mold base (2), wherein the aluminum column module (1) includes two sets of aluminum column modules with different heights; The head mold base (2) is composed of an upper and lower part, and the two parts are positioned by an arc-shaped slide rail (5) and bolts; the lower part (4) of the head mold base is fixed, and the pitch angle of the head mold is adjusted by sliding the upper part (3) of the head mold base; circular through holes (6) are arranged on both sides of the arc-shaped slide rail (5) at the lower part of the head mold base, and waist-shaped through holes (10) are arranged on the slide rail part at the upper part of the head mold base, which are used to fix the relative posture between the upper part (3) of the head mold base and the lower part (4) of the head mold base; The upper part (3) of the head mold base is provided with a head mold chin structure for fixing the chin strap of the bulletproof helmet; Positioning holes (11) are provided on both sides of the upper part (3) of the head mold base for positioning the special shaping mold for the cement; There are two sets of aluminum column modules, each set consists of four aluminum columns with the same structure, and the difference between the two sets of aluminum column modules is the height difference; a platform is arranged at the bottom of each aluminum column, and the platform is fixedly connected to the upper part of the head mold base.

2. The head model for testing the protective performance of a helmet according to claim 1, characterized in that: The top surface of the upper part (3) of the head mold base is provided with four threaded holes, and the bottom platform of the aluminum column is provided with a circular through hole. The upper part (3) of the head mold base is fixedly connected with the bottom platform of the aluminum column by bolts.

3. The head model for testing the protective performance of a helmet according to claim 1, characterized in that: The fastening bolts pass through the circular through holes on both sides of the slide rail at the lower part of the head mold base and the waist-shaped through holes (10) on the slide rail at the upper part of the head mold base, and are tightened with nuts to fix the relative posture between the upper part (3) of the head mold base and the lower part (4) of the head mold base.

4. The head model for testing the protective performance of a helmet according to claim 1, characterized in that: The lower part (4) of the head mold base is provided with four circular through holes at the bottom and is fixed to a corresponding target frame in the test site by bolts.

5. The head model for testing the protective performance of a helmet according to claim 1, characterized in that: It is necessary to select the number and installation positions of the aluminum columns according to the impact position of the next bullet-proof helmet test. If the next test is on the front of the bullet-proof helmet, install two aluminum columns on the rear of the head mold; if the next test is on the rear of the bullet-proof helmet, install two aluminum columns on the front of the head mold; if the next test is on the left side of the bullet-proof helmet, install two aluminum columns on the right side of the head mold; if the next test is on the right side of the bullet-proof helmet, install two aluminum columns on the left side of the head mold; if the next test is on the top of the bullet-proof helmet, install a set of aluminum columns with a lower height.

6. The head model for testing the protective performance of a helmet according to claim 1, characterized in that: The utility model also comprises a special shaping mold (14) for cement, and the special shaping mold (14) for cement is installed on the upper part (3) of the head mold base.

7. The head model for testing the protective performance of a helmet according to claim 6, characterized in that: The main body of the special shaping mold (14) for cement is an ellipsoidal shell whose inner wall is completely fitted with the outer surface of the aluminum column module and is spliced ​​into an ellipsoidal column shell. The top of the mold is open for filling cement inside.

8. The head model for testing the protective performance of a helmet according to claim 7, characterized in that: The two sides of the special shaping mold (14) for cement are provided with waist-shaped holes (15), and the cylindrical pins pass through the waist-shaped holes (15) and the positioning holes (11) of the upper part (3) of the head mold base in sequence.

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