Head model for testing protective performance of helmets

Abstract

This invention discloses a head model for testing the protective performance of helmets, comprising a head model base and aluminum column modules disposed on the upper part of the head model base. The aluminum column modules contain two sets of aluminum column modules of different heights. The head model base consists of upper and lower parts, which are positioned by an arc-shaped slide rail and bolts. The lower part of the head model base is fixed, and the pitch angle of the head model is adjusted by sliding the upper part of the head model base. A head model chin structure is provided on the upper part of the head model base for fixing the chin strap of a bulletproof helmet. Positioning holes are provided on both sides of the upper part of the head model base for positioning a special molding mold for clay. This invention can accurately test the height of bullet marks on helmets that undergo large deformation under impact. The same effect can be achieved on the front, rear, left, right, and top of the bulletproof helmet, solving the problem of the inapplicability of traditional molds to bulletproof helmets that undergo large deformation under impact.

Description

Technical Field

[0001] This invention relates to the field of helmet protection performance testing technology, and specifically to a head model for helmet protection performance testing. Background Technology

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

[0003] In the testing of the protective performance of bulletproof helmets, a helmet model (hereinafter referred to as a head model) is often required. The head model has four aluminum pillars at the top, and its outer contour is designed according to the standard adult head and face size. When conducting helmet protective performance testing, the middle of the aluminum pillars is filled with putty. Then, the helmet to be tested is placed on the putty-filled head model, and the chin strap is tightened. Then, ballistic tests are performed on the front, back, left, right, and top of the helmet, and the point of impact is located at the corresponding part of the putty. For example, the American Institute of Justice's bulletproof helmet standard (NIJ standard 0106.01), my country's military bulletproof helmet safety technical performance requirements (GJB 5115A-2012), and police bulletproof helmets and masks (GA293-2012) all have relevant regulations and requirements. At the same time, the standards have clear requirements for the height of bullet marks on bulletproof helmets under the impact of bullets or fragments. Based on this, the depth of the pit in the clay inside the head mold is used to evaluate the maximum deformation of the helmet during the impact process. When the bullet mark height is small, the pit depth of the clay can reflect the bullet mark height of the helmet well. As the bullet mark height increases, the deformation area of ​​the helmet increases accordingly. The four aluminum pillars 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 the testing requirements. For example, the new ultra-high molecular weight polyethylene fiber composite helmet still has 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 pillars of the head mold. At this time, the aluminum pillars exert additional local constraints on the helmet, thus affecting the accuracy of the test results.

[0004] Therefore, this invention designs a modular head model for testing the protective performance of helmets and a special molding mold for clay. Compared with traditional head models, it can more accurately test the true protective performance and bullet hole height of bulletproof helmets under impact and large deformation. Summary of the Invention

[0005] The purpose of this invention is to provide a head model for testing the protective performance of helmets, which can accurately test the height of bullet marks on helmets that undergo large deformation under impact. The same effect can be achieved on the front, back, left, right and top of bulletproof helmets, solving the problem of the inapplicability of traditional molds to bulletproof helmets that undergo large deformation under impact.

[0006] The technical solution to achieve the purpose of this invention is: a head model for testing the protective performance of a helmet, which consists of a head model base and an aluminum column module set on the upper part of the head model base. The aluminum column module contains two sets of aluminum column modules with different heights.

[0007] The head mold base consists of two parts, upper and lower, 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. The lower slide rail of the head mold base has circular through holes on both sides, and the upper slide rail of the head mold base has waist-shaped through holes, which are used to fix the relative posture between the upper and lower parts of the head mold base.

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

[0009] The upper part of the head mold base is provided with positioning holes on both sides for positioning the special shaping mold for clay.

[0010] There are two sets of aluminum column modules, each set consisting of four aluminum columns with similar structures. The difference between the two sets of aluminum column modules is their height. Each aluminum column has a platform at its bottom, which 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, and the bottom platform of the aluminum column is provided with a circular through hole. The upper part of the head mold base and the bottom platform of the aluminum column are fixedly connected 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 hole of the upper slide rail of the head mold base, and are tightened with nuts to fix the relative posture between the upper and lower parts of the head mold base.

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

[0014] Furthermore, the number and installation position of the aluminum pillars need to be selected based on the impact location of the next bullet test on the bulletproof helmet. If the next test is on the front of the bulletproof helmet, install two aluminum pillars on the back of the head mold; if the next test is on the rear of the bulletproof helmet, install two aluminum pillars on the front of the head mold; if the next test is on the left side of the bulletproof helmet, install two aluminum pillars on the right side of the head mold; if the next test is on the right side of the bulletproof helmet, install two aluminum pillars on the left side of the head mold; if the next test is on the top of the bulletproof helmet, install a set of aluminum pillars with a lower height.

[0015] Furthermore, the head model also includes a clay-specific shaping mold, which is installed on the upper part of the head model base.

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

[0017] Furthermore, the special molding mold for clay is provided with waist-shaped holes on both sides, 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 beneficial effects of the present invention are as follows:

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

[0020] (2) In this invention, for the bullet impact test scenario at the top of the bulletproof helmet, a set of aluminum column modules with a low height is designed to achieve the purpose of accurately measuring the height of the bullet marks 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, which can realize the pitch adjustment of the bulletproof helmet of the test subject, and facilitate the adjustment of the target angle of the bullet / fragment on the bulletproof helmet. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the modular head mold shape according to an embodiment of the present invention.

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

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

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

[0026] Figure 5These are two sets of aluminum column modules of different heights according to an embodiment of the present invention.

[0027] Figure 6 This is a special molding mold for clay in an embodiment of the present invention. Detailed Implementation

[0028] Combination Figure 1 , Figure 6 A modular head mold consists of a head mold base 2 and an aluminum column module 1 set above the head mold base 2, and also includes a special molding mold 14 for clay.

[0029] Combination Figure 2 , Figure 3 , Figure 4 The head mold base consists of upper and lower parts, which are positioned by an arc-shaped slide rail 5. The bottom of the lower part 4 of the head mold base is a platform structure with four vertical through holes 7. The positions of the through holes 7 correspond to the corresponding holes on the target frame in the testing area, and the head mold base can be fixed to the target frame in the testing area with bolts. With the lower part 4 of the head mold base fixed, the pitch angle of the head mold can be adjusted by sliding the upper part 3 of the head mold base. The lower part 4 of the head mold base has circular through holes 6 on both sides of the arc-shaped slide rail 5, and the upper part 3 of the head mold base has waist-shaped through holes 10. Fastening bolts are passed through the circular through holes 6, waist-shaped through holes 10, and circular through holes 6 in sequence before being tightened with nuts to fix the relative posture between the upper part 3 and the lower part 4 of the head mold base. The top surface of the upper part 3 of the head mold base has four threaded holes 8. The head mold base 2 has a head mold chin 9 structure for fixing the chin strap of the bulletproof helmet. The upper part of the head mold base is provided with positioning holes 11 on both sides for fixing the clay-specific shaping mold 13.

[0030] Combination Figure 1 , Figure 5 There are two sets of aluminum column modules, each set consisting of four aluminum columns 12 with similar structures. The difference between the two sets of aluminum column modules is their height. Each aluminum column 12 has a platform at its bottom with a circular through hole 13. 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 molding mold 14 for clay is a semi-ellipsoidal shell whose inner wall is completely attached to the outer surface of the aluminum column module 12. An elliptical cylindrical shell of a certain height is spliced ​​below. The top of the mold 14 is open for filling clay into it. A waist-shaped hole 15 is provided on each side of the elliptical cylindrical part. A cylindrical pin can pass through the waist-shaped hole 14 and be inserted into the positioning hole 15 of the head mold (upper) to limit the longitudinal displacement of the mold during the clay filling process.

[0032] Example

[0033] The solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings.

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

[0035] Combination Figures 1-4 Before the experiment, bolts of appropriate size are used to pass through the circular through-hole 7 on the platform of the lower part 4 of the head mold base and fix it to the corresponding target frame in the test area. Then, the upper part 3 of the head mold base is installed on the lower part 4 of the head mold base via the arc guide rail. Bolts are then passed through the circular through-hole 6, the waist-shaped through-hole 10, and the circular through-hole 6 in sequence and tightened with nuts to pre-fix the relative position of the lower part 4 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. Bolts are used to pass through the circular through-hole 13 on the bottom platform of the aluminum column 12 and screwed into the threaded hole 8 at the top of the upper part 3 of the head mold base to fix the aluminum column 12 to the top of the upper part of the head mold base. The number and installation position of the aluminum pillars 12 need to be selected according to the impact position of the next bullet test on the bulletproof helmet. If the next test is on the front of the bulletproof helmet, install two aluminum pillars on the rear of the head mold; if the next test is on the rear of the bulletproof helmet, install two aluminum pillars on the front of the head mold; if the next test is on the left side of the bulletproof helmet, install two aluminum pillars on the right side of the head mold; if the next test is on the right side of the bulletproof helmet, install two aluminum pillars on the left side of the head mold; if the next test is on the top of the bulletproof helmet, install a set of four aluminum pillars with a lower height. The special molding mold 14 for the clay is installed on the upper part 3 of the head mold base. The cylindrical pins are inserted sequentially through the waist-shaped hole 15 in the molding mold 14 and the positioning hole 11 in the upper part 3 of the head mold base. Cylindrical pins are inserted on both the left and right sides of the molding mold 14. The test clay is filled into the space between the inner wall of the molding mold 14 and the aluminum pillars 12 through the opening at the top of the molding mold 14, ensuring that the clay is uniform in texture, without gaps or voids, and has a smooth surface. Then, remove the cylindrical pin and take off the 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 lower rear edge of the bulletproof helmet coincides with the lower rear edge of the head mold. Use a special tensioning device to pull the bulletproof helmet upward to meet the specified tension requirements.

Claims

1. A head model for testing the protective performance of a helmet, characterized in that, It consists of a head mold base (2) and an aluminum column module (1) set on the upper part of the head mold base (2). The aluminum column module (1) contains two sets of aluminum column modules with different heights. The head mold base (2) consists of two parts, upper and lower, which 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). The arc-shaped slide rail (5) of the lower part of the head mold base is provided with circular through holes (6) on both sides, and the upper slide rail of the head mold base is provided with waist-shaped through holes (10) to fix the relative posture between the upper part (3) 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; The upper part (3) of the head mold base is provided with positioning holes (11) on both sides for positioning the special shaping mold for clay. There are two sets of aluminum column modules, each set consisting of four aluminum columns with the same structure. The difference between the two sets of aluminum column modules is their height. Each aluminum column has a platform at its bottom, which is fixedly connected to the upper part of the head mold base.

2. The head model for testing helmet protective performance 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 and the bottom platform of the aluminum column are fixedly connected by bolts.

3. The head model for testing helmet protective performance 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 bottom of the head mold base and the waist-shaped through hole (10) at the slide rail at the top of the head mold base, and are tightened with nuts to fix the relative posture between the upper part (3) and the lower part (4) of the head mold base.

4. The head model for testing helmet protective performance according to claim 1, characterized in that, The lower part (4) of the head mold base has four circular through holes, which are fixed to the corresponding target frame in the test site by bolts.

5. The head model for testing helmet protective performance according to claim 1, characterized in that, The number and installation position of the aluminum pillars need to be selected based on the impact location of the next bullet test on the bulletproof helmet. If the next test is on the front of the bulletproof helmet, install two aluminum pillars on the back of the head mold; if the next test is on the back of the bulletproof helmet, install two aluminum pillars on the front of the head mold; if the next test is on the left side of the bulletproof helmet, install two aluminum pillars on the right side of the head mold; if the next test is on the right side of the bulletproof helmet, install two aluminum pillars on the left side of the head mold; if the next test is on the top of the bulletproof helmet, install a set of aluminum pillars with a lower height.

6. The head model for testing helmet protective performance according to claim 1, characterized in that, It also includes a special molding mold (14) for clay, which is installed on the upper part (3) of the head mold base.

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

8. The head model for testing helmet protective performance according to claim 7, characterized in that, The special molding mold (14) for clay is provided with waist-shaped holes (15) on both sides, and the cylindrical pin passes through the waist-shaped holes (15) and the positioning holes (11) on the upper part (3) of the head mold base in sequence.

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