Information leakage suppression device

Abstract

The present invention provides an information leakage suppression device that can suppress the leakage of information from a hard disk by making it easier to render information on the hard disk unusable while keeping the height of the information leakage suppression device low. [Solution] The information leakage suppression device 1 comprises a base body 12 on which the hard disk is placed on the inner upper surface, a holder 14 placed in contact with the upper surface of the hard disk, the holder having a nozzle portion opening toward the upper surface of the hard disk, a hub combustion chamber 40 connected to the nozzle portion and burning explosives inside, a first combustion chamber 41 extending from the hub combustion chamber and burning explosives inside, and a second combustion chamber 42 extending from the hub combustion chamber in a direction different from the first combustion chamber and burning explosives inside, and a lid portion 16 placed in contact with the upper surface of the holder and formed in a flat plate shape.

Description

[Technical Field]

[0001] The present invention relates to an information leakage suppression device, for example, an information leakage suppression device that suppresses the leakage of information from a hard disk. [Background technology]

[0002] In recent years, various measures have been proposed to prevent the leakage of information stored on hard drives. While measures have been taken to prevent network intrusions into hard drives, a challenge remains in preventing information leakage from physical theft of computers, such as when a hard drive is stolen along with the computer, or when the computer is forcibly taken even if the theft is noticed.

[0003] For example, Patent Document 1 proposes a PC theft prevention system that uses the positional relationship between the PC main unit and peripheral devices to lock the hard disk installed in the PC main unit if the PC main unit is stolen. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2012-053815 [Overview of the project] [Problems that the invention aims to solve]

[0005] However, if the computer itself was stolen, it could be analyzed over time, potentially leading to the leakage of internal information.

[0006] Furthermore, in situations where it was absolutely necessary to quickly stop the leakage of information from a computer, traditional methods involved physically destroying the drive with a hammer or axe. However, hard drives are relatively robust because they are encased in die-cast aluminum metal and iron, and there were challenges such as the risk of failure in destroying the contents and the time it took.

[0007] Therefore, there is a need for stronger and more immediate means of preventing information leaks as a countermeasure against physical theft of personal computers.

[0008] This invention was made to solve these problems, and aims to provide an information leakage suppression device that can suppress information leakage from a hard disk by making it easier to render information on the hard disk unusable while suppressing the height of the information leakage suppression device. [Means for solving the problem]

[0009] To achieve the above objective, according to one embodiment of the present invention, an information leakage suppression device for suppressing information leakage from a hard disk comprises: a base body on which the hard disk is placed on the inner upper surface; a holder disposed in contact with the upper surface of the hard disk, the holder having a nozzle portion opening toward the upper surface of the hard disk, a hub combustion chamber connected to the nozzle portion and burning explosives inside, a first combustion chamber extending from the hub combustion chamber and burning explosives inside, and a second combustion chamber extending from the hub combustion chamber in a direction different from the first combustion chamber and burning explosives inside; and a lid portion disposed in contact with the upper surface of the holder and formed in the shape of a flat plate. According to an embodiment of the present invention configured as described above, the information leakage suppressing device includes a hub combustion chamber connected to the nozzle portion, a first combustion chamber extending from the hub combustion chamber, and a second combustion chamber extending from the hub combustion chamber in a direction different from the first combustion chamber. Thereby, the first combustion chamber and the second combustion chamber connected to the hub combustion chamber can relatively easily form a relatively large combustion area. Thereby, when a combustion area of a predetermined size is to be formed with respect to the opening area of the nozzle portion and the combustion gas flowing from the combustion chamber into the nozzle portion is to be accelerated, the heights of the first combustion chamber and the second combustion chamber can be easily adjusted, and the heights of the first combustion chamber and the second combustion chamber can be easily suppressed. Therefore, while suppressing the height of the information leakage suppressing device, it is easy to form a hole in the upper surface of the hard disk. Therefore, while suppressing the height of the information leakage suppressing device, it is easy to make the information in the hard disk unusable, and the information leakage from the hard disk can be suppressed.

Effect of the Invention

[0010] According to the information leakage suppressing device of the present invention, while suppressing the height of the information leakage suppressing device, it is easy to make the information in the hard disk unusable, and the information leakage from the hard disk can be suppressed.

Brief Description of the Drawings

[0011] [Figure 1] It is a side view showing the internal structure in the case of a personal computer in which the information leakage suppressing device according to the first embodiment of the present invention is arranged with the side panel removed. [Figure 2] It is a schematic perspective view of the information leakage suppressing device according to the first embodiment of the present invention. [Figure 3] It is an exploded perspective view of the information leakage suppressing device according to the first embodiment of the present invention. [Figure 4] In the information leakage suppressing device according to the first embodiment of the present invention, it is a cross-sectional view taken along the line IV-IV of FIG. 2. [Figure 5] In the information leakage suppressing device according to the first embodiment of the present invention, it is a cross-sectional view taken along the line V-V of FIG. 4. [Figure 6]It is an enlarged cross-sectional view showing the vicinity of the hard disk in FIG. 4. [Figure 7] It is a top view of the holder of the information leakage prevention device according to the first embodiment of the present invention as viewed from above. [Figure 8] In the information leakage prevention device according to the first embodiment of the present invention, it is a cross-sectional view taken along line VII-VII in FIG. 4. [Figure 9] In the information leakage prevention device according to the first embodiment of the present invention, it is a cross-sectional view taken along line IX-IX in FIG. 4. [Figure 10] It is a block diagram showing the configuration of the information leakage prevention device according to the first embodiment of the present invention. [Figure 11] It is a time chart showing the combustion timing of gunpowder in the combustion chamber in the information leakage prevention device according to the first embodiment of the present invention. [Figure 12] In the information leakage prevention device according to the first embodiment of the present invention, it is a schematic configuration diagram schematically showing the relationship between the platter of the hard disk and the nozzle portion. [Figure 13] In the information leakage prevention device according to the first embodiment of the present invention, it is a cross-sectional view showing a modified example of FIG. 6. [Figure 14] It is a top view of the holder of the information leakage prevention device according to the second embodiment of the present invention. [Figure 15] In the information leakage prevention device according to the second embodiment of the present invention, it is a cross-sectional view taken along line XV-XV in FIG. 14. [Figure 16] In the information leakage prevention device according to the second embodiment of the present invention, it is a cross-sectional view taken along line XVI-XVI in FIG. 14.

Embodiments for Carrying Out the Invention

[0012] Hereinafter, the information leakage prevention device 1 according to the first embodiment of the present invention will be described with reference to the accompanying drawings. The embodiments described herein are illustrative and will be apparent to those skilled in the art that many modifications, changes, and substitutions are possible within the spirit and scope of the present invention. Therefore, the present invention is not limited to the embodiments disclosed, and various modifications, changes, etc., are possible in its form and details without departing from the claims. Furthermore, the components disclosed in the specification can be freely combined.

[0013] As shown in Figure 1, the information leakage suppression device 1 according to the first embodiment of the present invention can provide a device to suppress information leakage from a hard disk. The information leakage suppression device 1 also functions as a device to destroy the hard disk 50 (see Figure 6) so that the information inside the hard disk becomes unusable. For example, if the hard disk is about to be forcibly taken away along with the computer, or if it has been taken away, the information leakage suppression device 1 can immediately render the information inside the hard disk unusable by igniting explosives in a short period of a few seconds to more than ten seconds, thereby suppressing information leakage from the hard disk. Generally, the hard disk 50 has a hard disk case with the lower part made of die-cast aluminum and an iron plate of 0.3 mm or 0.5 mm thickness placed on top. Therefore, it is relatively hard and difficult to destroy even if one tries to destroy it physically. In the following description of the first embodiment of the present invention, as shown in Figure 2, one longitudinal side of the information leakage suppression device 1 is referred to as the front, and the opposite side as the rear. When the information leakage suppression device 1 is facing forward, the right hand side is referred to as the right side, the left hand side as the left side, the upper side of the information leakage suppression device 1 is referred to as the upper side, and the lower side is referred to as the lower side.

[0014] As shown in Figure 1, the information leakage suppression device 1 is located inside the case 3 of a personal computer (PC) 2. PC 2 is, for example, a stationary PC placed on an office desk. The case 3 is box-shaped; Figure 1 shows the case 3 with its side panel removed to reveal its internal structure. PC 2 comprises a motherboard 6 on which the CPU and memory are located, a first power supply unit 7 that supplies power to the motherboard 6 and the hard disk 50 (see Figure 6), the hard disk 50, and the information leakage suppression device 1. The information leakage suppression device 1 has a hard disk 50 built inside and, as will be described later, is roughly the same size as a standard 3.5-inch hard disk drive. Therefore, the information leakage suppression device 1 can be relatively easily housed in the space of two 3.5-inch drive bays 9 inside the case 3 of a commercially available PC 2. As shown in Figure 1, multiple 3.5-inch drive bays 9 are formed inside the case 3. Users can, for example, add hard disks or the like by fixing them into these 3.5-inch drive bays 9. Case 3 also contains cooling fans 11, etc. The internal structure of a typical personal computer 2 will not be explained.

[0015] As shown in Figures 2 and 3, the information leakage suppression device 1 comprises a base body 12 having a receiving section for receiving the hard disk 50, a holder 14, and a lid 16.

[0016] As shown in Figure 3, the base body 12 accommodates the hard disk 50 on its inner upper surface. Viewed from above, the base body 12 is rectangular, with a length (depth) of 14.6 cm in the front-to-back direction and a length (width) of 10.2 cm in the left-to-right direction. The external dimensions of the base body 12 are the same as those of a so-called 3.5-inch standard hard disk drive. The base body 12 is formed so that its outer periphery rises from a flat base, with a recessed portion 12a in the center. The recessed portion 12a forms a receiving portion for the hard disk 50. The hard disk 50 is, for example, a so-called 2.5-inch standard hard disk drive. The recessed portion 12a is formed such that a small gap is created on the outside when, for example, a so-called 2.5-inch standard hard disk drive is placed inside. The bottom surface of the recessed portion 12a is flat and rectangular. For example, with a so-called 2.5-inch hard disk drive placed inside, the top surface 50a of the hard disk drive 50 and the top surface 12b of the outer periphery of the base body 12 are formed to be at the same height. Therefore, the holder 14 and the base body 12 are combined with the holder 14 in contact with both the top surface 50a of the hard disk drive 50 and the top surface 12b of the base body 12. By forming it in this way, a commercially available high-performance so-called 2.5-inch hard disk drive can be used, and the overall external size of the information leakage suppression device 1 is the same as two slots of a so-called 3.5-inch hard disk drive (for example, the external size of two so-called 3.5-inch hard disk drives stacked on top of each other), and it can be placed in the area of ​​two hard disk storage slots of a general personal computer. Furthermore, since a single screw fastens the lid 16 and the base body 12 and passes through the holder 14, it is possible to construct the information leakage prevention device 1 even if the size of the hard disk drive to be received in the recess differs slightly. The size and shape of the information leakage prevention device 1 are not limited to the same external dimensions as a 3.5-inch standard hard disk drive, and may be formed to any size and dimensions. While changing the overall size of the information leakage prevention device 1 may reduce its convenience in terms of PC placement, it will still maintain a certain level of effectiveness as an information leakage prevention device.

[0017] The base body 12 is made of a stainless steel metal component. The base body 12 forms an exhaust passage 12c that extends from the space formed between the inner surface of the base body 12 and the hard disk 50 to the outside of the base body 12. The formation of the exhaust passage 12c prevents the expanded gas from being exhausted through the exhaust passage 12c when the gunpowder burns explosively, thus preventing the base body 12, holder 14, and lid 16 from exploding and damaging surrounding objects.

[0018] As shown in Figure 6, the hard disk 50, which is placed on the base body 12, will be described below. The hard disk 50 is, for example, a so-called 2.5-inch standard hard disk 50 device. The hard disk 50 generally comprises a hard disk structure 51 whose lower part is made of die-cast aluminum, a spindle motor unit 52, a platter 53, an actuator 54, a magnetic head 55, and a hard disk case 56, all of which are arranged on the hard disk structure 51. Note that the internal structure of the hard disk 50 is not shown in Figures 4 and 5.

[0019] The hard disk structure 51 is provided at the base of the hard disk 50. The spindle motor section 52, actuator 54, etc. are attached to the upper side of the hard disk structure 51. The hard disk structure 51 is formed in a rectangular shape when viewed from above. The hard disk structure 51 itself constitutes the lower part of the hard disk case 56 and is fixed to the hard disk case 56 around its outer circumference. The lower part of the hard disk structure 51 is made of a metal member, such as aluminum die-cast.

[0020] The spindle motor section 52 is formed to rise vertically from the hard disk structure 51. The spindle motor section 52 is cylindrical in shape. The spindle motor section 52 houses a spindle motor and is configured to rotate the platters 53 around the spindle motor section 52 in response to the rotation of the spindle motor. The inner circumference of the platters 53 is connected to the outer circumference of the spindle motor section 52. For example, four platters 53 are connected to the spindle motor section 52 in a vertically aligned configuration. The spindle motor section 52 is configured to rotate at a predetermined rotational speed.

[0021] The platter 53 is formed on a disk. The platter 53 is formed on a thin flat plate. The platter 53 is formed in a circular shape of a predetermined diameter when viewed from above. The platter 53 has a storage area on its upper surface and is configured to store a large amount of data. The platter 53 has a layer of magnetic material for recording on its upper surface. The platter 53 is connected to the spindle motor unit 52 at its center. This is configured so that the platter 53 rotates in conjunction with the rotation of the spindle motor unit 52. The magnetic head 55 moves onto the platter 53 so that the magnetic head 55 can read the information stored on the platter 53. The platter 53 is formed by, for example, four platters 53, and the four platters 53 are arranged vertically. The storage layer and magnetic layer of the platter 53 constitute a delicate storage area and are susceptible to serious damage that renders them unusable even by slight heat or dirt such as soot.

[0022] The actuator 54 is located on the outer side of one side of the platter 53, and is positioned on the hard disk structure 51. The actuator 54 is formed between the platter 53 and the third wall 56c, which will be described later. The actuator 54 is connected to the magnetic head 55 and is configured to move the magnetic head 55 in the scanning direction. The actuator 54 is also formed between the first wall 56a (see Figure 3) and the second wall 56b of the hard disk case 56.

[0023] The magnetic head 55 is located inside the hard disk case 56. The magnetic head 55 has a fork-shaped data reading section. Initially, the magnetic head 55 is located outside the platter 53. When reading data, the magnetic head 55 is positioned on the platter 53 by the actuator 54. The magnetic head 55 has the function of writing data to the platter 53 and reading data from the platter 53.

[0024] The hard disk case 56 constitutes the outer case of the hard disk 50. The hard disk case 56 is formed from a first wall 56a (see Figure 3) extending in the longitudinal direction, a second wall 56b extending parallel to the first wall 56a, a third wall 56c extending in the transverse direction from one end of the first wall 56a, and a fourth wall 56d extending parallel to the third wall 56c. The third wall 56c is a wall portion provided on the magnetic head 55 and actuator 54 side. The fourth wall 56d is a wall portion provided on the platter 53 side. The flat plate 56e on the top surface of the hard disk 50 forms the top of the hard disk case 56.

[0025] Next, as shown in Figure 3, the holder 14 is positioned so as to be in contact with the top surface of the hard disk 50. When viewed from above, the holder 14 is formed in a rectangular shape, with a length (depth) of 14.6 cm in the front-to-back direction and a length (width) of 10.2 cm in the left-to-right direction. The external dimensions of the holder 14 are the same as those of a so-called 3.5-inch standard hard disk drive. The holder 14 forms a flat plate. The holder 14 is made of a stainless steel metal component.

[0026] As shown in Figure 4, the holder 14 comprises a nozzle portion 21, a hub combustion chamber 40, a first combustion chamber 41, and a second combustion chamber 42. The hub combustion chamber 40, the first combustion chamber 41, and the second combustion chamber 42 form a single space. The nozzle portion 21 opens toward the upper surface of the hard disk 50. As shown in Figure 4, the nozzle portion 21 extends upward from the lower surface 14a inside the holder 14. The nozzle portion 21 forms a cylindrical passage. The nozzle portion 21 is formed on the metal plate of the holder 14. The diameter of the horizontal cross-section of the nozzle portion 21 is constant from the bottom to the top of the nozzle portion 21. The nozzle portion 21 comprises an inner opening on the combustion chamber side and an outer opening on the hard disk 50 side. The outer opening of the nozzle portion 21 is formed on the lower surface of the holder 14. The inner opening of the nozzle portion 21 is formed on the bottom surface of the combustion chamber. The nozzle portion 21 is connected to the bottom surface of the combustion chamber. The nozzle portion 21 is not limited to a cylinder, and may be formed in a square cross-section or other shapes. The diameter of the nozzle portion 21 is, for example, a value within the range of 4 mm to 15 mm, for example, a value within the range of 4 mm to 10 mm, and for example, a value within the range of 4 mm to 8 mm. The length of the nozzle portion 21 is, for example, a value within the range of 2 mm to 10 mm, and for example, a length within the range of 2 mm to 5 mm. No explosives are placed inside the nozzle portion 21, but explosives may be placed inside. As a modification, as shown in Figure 13, the nozzle portion 21 may be formed so that the opening area widens from the top to the bottom. By forming the nozzle portion 21 so that the opening area widens from the top to the bottom, resistance to the flow of combustion gases is reduced, and the hole can be formed efficiently.

[0027] As shown in Figure 4, the nozzle portion 21 forms an inner opening 21a with a first area A1. The inner opening 21a is formed in a circular shape. However, the inner opening may be formed in any shape. The diameter of the inner opening is a diameter value within the range of 4 mm to 10 mm, for example, a diameter value within the range of 4 mm to 6 mm. The outer opening is formed in the same shape as the inner opening. For example, the outer opening 21b is formed in a circular shape. However, the outer opening may be formed in any shape. The diameter of the outer opening 21b is a diameter value within the range of 4 mm to 10 mm, for example, a diameter value within the range of 4 mm to 6 mm. The outer opening may be formed in a different shape from the inner opening. The first area A1 of the nozzle portion 21 can be, for example, the area of ​​a circle with a diameter of 4 mm to 6 mm. The first area A1 is, for example, approximately 19.6 mm². 2 It can be done.

[0028] Furthermore, for example, the central axis X1 of the nozzle section 21 (see Figure 6) is positioned perpendicular to the hard disk 50. In a top view, the central axis X1 of the nozzle section 21 is positioned offset from the spindle motor section 52 of the platter 53 of the hard disk 50. As a result, the combustion of gunpowder in the hub combustion chamber 40, the first combustion chamber 41, and the second combustion chamber 42 (hereinafter referred to as "combustion chambers, etc.") causes flames to enter the hard disk 50 at a position offset from the spindle motor section 52 of the platter, as shown by arrow D1 (see Figure 6), thereby efficiently rendering the stored data on the platter unusable. The central axis X1 of the nozzle section 21 is positioned offset from the spindle motor section 52 of the platter of the hard disk 50 when viewed from above. As a result, the combustion of the gunpowder 60 in the combustion chamber causes the flame to enter the hard disk 50 from the nozzle section 21 at a position offset from the spindle motor section 52 of the platter. This makes it easier for the flame and the main stream of high-temperature gas associated with the flame to spread concentrically around the lower front portion of the nozzle section 21 and the platter in the lower front portion, efficiently rendering the stored data on the platter unusable. The combustion chamber is configured to contain the gunpowder 60. The gunpowder 60 can be made from common gunpowder, such as black powder, smokeless powder, or solid propellant. For example, the gunpowder 60 may be made from a mixture of a flammable rubber base material with an oxidizer or metal particles.

[0029] The length of the explosive arrangement is the length of the explosive 60 arranged from the inlet of the combustion chamber, etc., to the end opposite the nozzle section 21. The combustion chamber, etc., is formed to accommodate an explosive of a first capacity E1. The first capacity E1 is, for example, the volume from the inlet of the combustion chamber, etc., to the end opposite the nozzle section 21.

[0030] The flame and combustion gas ejected from the nozzle 21 can form a hole in the upper surface of the hard disk case 56, as shown by arrow D1 (see Figure 6). The nozzle 21 mainly forms a hole in the upper surface of the hard disk case 56, but it may also render some of the stored data on the platters 53 unusable. The nozzle 21 is located above the end 53d of the platter opposite to the actuator side. The nozzle 21 can be positioned at any location. Note that the internal structure of the hard disk 50 is not shown in Figures 4 and 5.

[0031] The hub combustion chamber 40 is connected to the nozzle section 21. The hub combustion chamber 40 is connected to the upper end of the nozzle section 21. The hub combustion chamber 40 is positioned vertically above the nozzle section 21. The nozzle section 21 is positioned so as to overlap the lower side of the hub combustion chamber when viewed from above. The hub combustion chamber 40 forms a space above the nozzle section 21 that serves as a hub through which the combustion gas passes. The hub combustion chamber 40 forms, for example, a rectangular parallelepiped-shaped space within the space connecting the hub combustion chamber 40, the first combustion chamber 41, and the second combustion chamber 42. The hub combustion chamber 40 forms, for example, a cubic-shaped space. The hub combustion chamber 40 may be formed by a space of any shape. For example, the hub combustion chamber 40 may be formed by a cylindrical space. The hub combustion chamber 40 is formed in a square shape when viewed from above. The hub combustion chamber 40 forms a storage section for the gunpowder 60 for initial combustion. The hub combustion chamber 40 burns gunpowder 60 inside. The hub combustion chamber 40 has a first opening 40a connected to a first combustion chamber and a second opening 40b connected to a second combustion chamber. The hub combustion chamber 40 functions as a hub that receives combustion gases from multiple combustion chambers extending in different directions.

[0032] The first combustion chamber 41 extends from the hub combustion chamber 40 and burns gunpowder inside. The first combustion chamber 41 extends laterally from the hub combustion chamber 40. The first combustion chamber 41 is formed to extend linearly in the horizontal direction. Because the first combustion chamber 41 can be positioned laterally from the hub combustion chamber 40, it is easy to add additional combustion chambers. Also, because the first combustion chamber 41 can be positioned laterally, it is easy to make the length and volume of the first combustion chamber 41 relatively large. The first inlet 41a of the first combustion chamber 41 is connected to the first opening 40a of the hub combustion chamber 40. The bottom surface of the first combustion chamber 41 is formed by a plane extending in the horizontal direction. The upper end of the first combustion chamber 41 is formed on the upper surface of the holder 14. The first combustion chamber 41 extends along the longitudinal direction of the holder 14. When viewed from above, the first combustion chamber 41 forms a roughly rectangular groove. The first combustion chamber 41 is formed in a rectangular shape, for example, a square shape, in its longitudinal cross-section. The ratio of the height H1 of the first combustion chamber 41 to its width W1 is a ratio within the range of 1:1 to 1:4, for example, a ratio within the range of 1:1.1 to 1:4, for example, 1:2. The longitudinal length L1 of the first combustion chamber 41 is a length within the range of 20 mm to 50 mm. The short-side length (width) W1 of the first combustion chamber 41 is a length within the range of 5 mm to 20 mm. The height H1 of the first combustion chamber 41 is a height within the range of 3 mm to 10 mm. The longitudinal central axis C1 of the first combustion chamber 41 is perpendicular to the central axis X1 of the nozzle section 21. The longitudinal central axis C1 of the first combustion chamber 41 is common to the longitudinal central axis C2 of the second combustion chamber.

[0033] The first combustion chamber 41 burns the gunpowder 60 placed inside. The gunpowder 60 is distributed throughout the first combustion chamber 41 to a degree that is relatively constant. For example, the gunpowder 60 is distributed from the inlet of the first combustion chamber 41 to the end opposite the nozzle 21. The gunpowder 60 in the first combustion chamber 41 is formed to enable end-face combustion, which helps to maintain a relatively constant combustion area. For example, the combustion area of ​​the gunpowder in the first combustion chamber 41 is equal to the cross-sectional area of ​​the longitudinal section of the first combustion chamber 41. The first combustion chamber 41 forms the combustion surface of the second area A2. For example, the first combustion surface B1 corresponds to the longitudinal section of the first combustion chamber 41. The area of ​​the first combustion surface B1 corresponds to the combustion area of ​​the gunpowder in the combustion chamber. The first area of ​​the inner opening of the nozzle portion 21 is smaller than the second area A2 of the first combustion chamber 41 and the second combustion chamber 42. This configuration narrows the combustion gas flow path from the combustion chambers to the nozzle portion 21, accelerating the combustion gas flowing into the nozzle portion 21 from the combustion chambers and facilitating the formation of a hole on the upper surface of the hard disk 50. The second area A2 of the first combustion chamber 41 and the second combustion chamber 42 is, for example, 100 mm². 2 The area can be such that the combustion area of ​​the first combustion chamber 41 is, for example, approximately 50 mm². 2 This can be achieved. As the combustion of the gunpowder progresses, the combustion surface moves away from the inlet of the first combustion chamber 41. Although the combustion surface moves, the combustion area of ​​the combustion surface remains almost constant. The combustion surface is oriented perpendicular to the inner and outer openings of the nozzle portion 21. The direction of combustion of the gunpowder in the first combustion chamber 41, for example, the direction of movement of the combustion surface, is different from the direction in which the nozzle portion 21 extends.

[0034] The second combustion chamber 42 extends from the hub combustion chamber 40 in a direction different from that of the first combustion chamber 41 and burns gunpowder inside. The second combustion chamber 42 extends from the hub combustion chamber 40 in a direction opposite to that of the first combustion chamber 41. This makes it easier for the combustion flame from the first combustion chamber 41 to transfer to the second combustion chamber 42 even if combustion is poor in the second combustion chamber 42, making it easier to maintain combustion in both the first and second combustion chambers 41 and 42. In addition, the first combustion chamber 41 and the second combustion chamber 42 can be arranged relatively widely and efficiently, making it easier to increase the combustion area. The second combustion chamber 42 extends laterally from the hub combustion chamber 40. The second combustion chamber 42 is formed to extend linearly in the horizontal direction. Since the second combustion chamber 42 can be arranged laterally from the hub combustion chamber 40, it is easier to add additional combustion chambers. Furthermore, since the second combustion chamber 42 can be positioned laterally, it is easy to make the length and volume of the second combustion chamber 42 relatively large. The second inlet 42a of the second combustion chamber 42 is connected to the second opening 40b of the hub combustion chamber 40. The bottom surface of the second combustion chamber 42 is formed by a plane extending horizontally. The upper end of the second combustion chamber 42 is formed on the upper surface of the holder 14. The second combustion chamber 42 extends along the longitudinal direction of the holder 14. In a top view, the second combustion chamber 42 forms a roughly rectangular groove. In a longitudinal cross-section, the second combustion chamber 42 is formed in a square shape, for example, a rectangular shape. The ratio of the height to the width in the lateral direction of the second combustion chamber 42 is a ratio of values ​​within the range of 1:1 to 1:4, for example, a ratio of values ​​within the range of 1:1.1 to 1:4, for example, 1:2. The longitudinal length L2 of the second combustion chamber 42 is a length of value within the range of 20 mm to 50 mm. The length (width) W2 of the second combustion chamber 42 in the short direction is within the range of 5 mm to 20 mm. The height H2 of the second combustion chamber 42 is within the range of 3 mm to 10 mm. The longitudinal central axis C2 of the second combustion chamber 42 is perpendicular to the central axis X1 of the nozzle section 21. The longitudinal central axis C2 of the second combustion chamber 42 is the same as the longitudinal central axis C1 of the first combustion chamber 41. The size and shape of the second combustion chamber 42 are the same as those of the first combustion chamber 41. For example, the first capacity E1 of the first combustion chamber 41 is the same as the second capacity E2 of the second combustion chamber 42.

[0035] The second combustion chamber 42 burns the gunpowder 60 placed inside. The gunpowder 60 is distributed throughout the second combustion chamber 42 to a degree that is roughly the same. For example, the gunpowder 60 is distributed in the second combustion chamber 42 from the second inlet 42a to the end opposite the nozzle 21. The gunpowder 60 in the second combustion chamber 42 is formed to enable end-face combustion. For example, the combustion area of ​​the gunpowder in the second combustion chamber 42 is equal to the cross-sectional area of ​​the longitudinal section of the second combustion chamber 42. The second combustion chamber 42 forms the second combustion surface B2 of the second area A2. For example, the second combustion surface B2 corresponds to the longitudinal section of the second combustion chamber 42. The area of ​​the second combustion surface B2 corresponds to the combustion area of ​​the gunpowder in the second combustion chamber 42. The first area A1 of the inner opening of the nozzle portion 21 is smaller than the second area A2 of the first combustion chamber 41 and the second combustion chamber 42. This configuration narrows the combustion gas flow path from the combustion chambers to the nozzle portion 21, accelerating the combustion gas flowing into the nozzle portion 21 from the combustion chambers and facilitating the formation of holes on the upper surface of the hard disk 50. The second area A2 of the first combustion chamber 41 and the second combustion chamber 42 is, for example, 100 mm². 2 The area can be such that the combustion area of ​​the second combustion chamber 42 is, for example, approximately 50 mm². 2 This can be achieved. As the combustion of the gunpowder progresses, the combustion surface moves away from the inlet of the second combustion chamber 42. Although the combustion surface moves, the combustion area of ​​the combustion surface remains almost constant. The combustion surface is oriented perpendicular to the inner and outer openings of the nozzle portion 21. The direction of combustion of the gunpowder in the second combustion chamber 42, for example, the direction of movement of the combustion surface, is different from the direction in which the nozzle portion 21 extends.

[0036] The combined second area A2 of the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42 is an area within the range of 2 to 4 times the first area A1 of the inner opening 21a of the nozzle section 21. By having the combined second area A2 of the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42 be a predetermined multiple of the first area A1 of the inner opening 21a of the nozzle section 21, the proportion to which the combustion gas flow path from the first combustion chamber 41 and the second combustion chamber 42 to the nozzle section 21 is narrowed can be adjusted. For example, it can be adjusted to suppress the degree to which the combustion gas flowing into the nozzle section 21 from the combustion chamber, etc. is accelerated or to suppress the risk of combustion gas choking. In this way, by considering the combined area of ​​the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42, the degree of freedom of the individual shapes of the first combustion chamber 41 and the second combustion chamber 42 can be improved. For example, the first combustion chamber 41 or the second combustion chamber 42 can be formed in a relatively low rectangular shape. By considering the second area A2, which is the sum of the combustion surfaces of the first combustion chamber 41 or the second combustion chamber 42, the height of each can be suppressed while also suppressing the individual widths. For example, the second area A2 can be 100 mm 2 If you want to achieve a certain area, and you want to adjust it using only the area of ​​one combustion chamber, and you want the height of the combustion chamber to be 5 mm, then the width of the combustion chamber must be 20 mm, requiring the formation of a wide combustion chamber. In this way, if the ratio of the height to width of the combustion chamber is 1:4, not only does it become more difficult to construct the combustion chamber, but the gunpowder is more likely to cool during combustion, potentially leading to unstable combustion such as combustion stopping. In contrast, for example, when combustion is performed in multiple combustion chambers, such as the first combustion chamber 41 and the second combustion chamber 42, if you want the height of each combustion chamber to be 5 mm, then the width of each combustion chamber must be 10 mm, and the area of ​​each combustion surface must be 50 mm 2 As the area of ​​the second area A2, 100mm 2The area can be set to this. If the relationship between the height and width of the combustion chamber is within a predetermined range, such as between 1:1 and 1:3, it becomes easier to construct the combustion chamber, and the risk of combustion stopping due to the gunpowder being cooled by the metal plate during combustion is reduced, making it easier to continue combustion. In addition, the height of the first combustion chamber 41 and the second combustion chamber 42 can be suppressed to realize a second area A2 total for the first combustion chamber 41 and the second combustion chamber 42. Furthermore, it is possible to achieve efficient throttling of the combustion gas flow path from the first combustion chamber 41 and the second combustion chamber 42 to the nozzle section 21, as well as improve the ease of constructing the first combustion chamber 41 and the second combustion chamber 42, and to suppress the risk of combustion gas choking at the throttling of the combustion gas flow path.

[0037] The combined second area A2 of the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42 is three times the area A1 of the inner opening 21a of the nozzle section 21. By having the combined second area A2 of the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42 be a predetermined multiple of the area A1 of the inner opening 21a of the nozzle section 21, the ratio in which the combustion gas flow path from the first combustion chamber 41 and the second combustion chamber 42 to the nozzle section 21 is narrowed can be adjusted to a ratio of 3:1 from the second area A2 to the first area A1. For example, this can be adjusted to suppress the degree to which the combustion gas flowing into the nozzle section 21 from the combustion chamber, etc., is accelerated, or to suppress the risk of combustion gas choking. In this way, efficient throttling of the combustion gas flow path from the first combustion chamber 41 and the second combustion chamber 42 to the nozzle section 21 can be achieved, as well as the ease of constructing the first combustion chamber 41 and the second combustion chamber 42, and the risk of combustion gas choking at the throttling of the combustion gas flow path can be improved.

[0038] By considering the total area of the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42, the degrees of freedom of the individual shapes of the first combustion chamber 41 and the second combustion chamber 42 can be improved. For example, the first combustion chamber 41 or the second combustion chamber 42 can be formed in a rectangular shape with a relatively low height. By considering the second area A2 of the total combustion surfaces of the first combustion chamber 41 or the second combustion chamber 42, while suppressing their respective heights, their respective widths can also be suppressed. For example, when combustion is carried out in a plurality of combustion chambers such as the first combustion chamber 41 and the second combustion chamber 42, if the height of each combustion chamber is set to 5 mm, the width of each combustion chamber will be 10 mm, and the area of each combustion surface will be 50 mm 2 as the area, the second area A2 can be made 100 mm 2 as the area. If the relationship between the height and width of the combustion chamber is within a predetermined range such that it is within a certain range, it becomes easier to construct the combustion chamber, and during combustion, the gunpowder is less likely to be cooled, and combustion can be made more continuous. Also, by suppressing the heights of the first combustion chamber 41 and the second combustion chamber 42, the second area A2 of the total of the first combustion chamber 41 and the second combustion chamber 42 can be realized. For example, if the diameter of the inner opening 21a of the nozzle portion 21 is 5 mm, and the first area A1 of the inner opening 21a which is a circle with a radius of 2.5 mm is approximately 19.6 mm 2 as the area, the second area A2 will be approximately 58.8 mm which is three times that. 2 Thus, one combustion surface will be approximately 29.4 mm which is half of that. 2 For example, if the height H1 of the first combustion chamber 41 is set to approximately 5 mm, the width W1 of the first combustion chamber 41 with an area of 29.4 mm 2 can be approximately 5.88 mm. If the height H2 of the second combustion chamber 42 is set to approximately 5 mm, similarly, the width W2 of the second combustion chamber 42 can be approximately 5.88 mm. If the relationship between the height and width of the combustion chamber is within a predetermined range such that it is within the range of 1:1 to 1:3, it becomes easier to construct the combustion chamber than in a flat shape, and during combustion, the gunpowder is less likely to be cooled, and combustion can be made more continuous. Also, by suppressing the heights of the first combustion chamber 41 and the second combustion chamber 42, the second area A2 of the total of the first combustion chamber 41 and the second combustion chamber 42 can be realized.

[0039] The first combustion surface B1 and the second combustion surface B2 are set to proportionally divide the second area A2, and the first combustion chamber 41 is formed to have the proportionally divided first combustion surface B1, and the second combustion chamber 42 is formed to have the proportionally divided second combustion surface B2. By considering the combined area of ​​the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42, and setting the first combustion surface B1 and the second combustion surface B2 to proportionally divide the second area A2, the degree of freedom for the individual shapes of the first combustion chamber 41 and the second combustion chamber 42 can be increased. For example, the first combustion chamber 41 or the second combustion chamber 42 can be formed into a relatively low rectangular shape. By considering the combined second area A2 of the combustion surfaces of the first combustion chamber 41 or the second combustion chamber 42, the height of each can be suppressed while also suppressing the individual widths. By setting the first combustion surface B1 and the second combustion surface B2 to proportionally divide the second area A2, the height of the individual combustion chambers can be easily suppressed. Therefore, the thickness of the holder 14 can be further reduced. Therefore, the overall height of the information leakage suppression device 1 can be further reduced, and for example, the information leakage suppression device 1 can be easily fitted into the area of ​​one slot of a 3.5-inch drive bay 9. In other words, the information leakage suppression device 1 can be formed to have the same external dimensions, such as height, length, and width, as a commercially available 3.5-inch hard disk for a 3.5-inch drive bay 9.

[0040] For example, the first combustion surface B1 and the second combustion surface B2 are set to divide the second area A2 in half, and the first combustion chamber 41 is formed to have the first combustion surface B1 divided in half, and the second combustion chamber 42 is formed to have the second combustion surface B2 of the same size as the first combustion surface B1. By considering the total area of ​​the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42, and setting the first combustion surface B1 and the second combustion surface B2 to divide the second area A2 in half, the degree of freedom for the individual shapes of the first combustion chamber 41 and the second combustion chamber 42 can be increased. For example, the first combustion chamber 41 or the second combustion chamber 42 can be formed into a relatively low rectangular shape. By considering the total second area A2 of the combustion surfaces of the first combustion chamber 41 or the second combustion chamber 42, the height of each can be suppressed while also suppressing the individual widths. By setting the first combustion surface B1 and the second combustion surface B2 to proportionally divide the second area A2, the height of the individual combustion chambers can be easily suppressed. Therefore, the thickness of the holder 14 can be further reduced. Therefore, the overall height of the information leakage suppression device 1 can be further reduced, and for example, the information leakage suppression device 1 can be easily fitted into the area of ​​one slot of a 3.5-inch drive bay 9. In other words, the information leakage suppression device 1 can be formed to have the same external dimensions, such as height, length, and width, as a commercially available 3.5-inch hard disk for a 3.5-inch drive bay 9.

[0041] The first combustion chamber 41 has a rectangular cross-section, and the ratio of its length to its width is within the range of 1:1 to 1:3. The second combustion chamber 42 also has a rectangular cross-section, and the ratio of its length to its width is within the range of 1:1 to 1:3. If the relationship between the height and width of the combustion chamber is within a predetermined range, such as 1:1 to 1:3, it becomes easier to construct the combustion chamber, and the gunpowder is less likely to be cooled by the metal plate during combustion, making it easier to continue combustion. In addition, by suppressing the height of the first combustion chamber 41 and the second combustion chamber 42, it becomes easier to achieve the second area A2, which is the sum of the first and second combustion chambers 41 and the second combustion chamber 42. Furthermore, the combustion surface of the combustion chamber can be maintained relatively stably by the rectangular shape of the combustion surface, making it easier to stably continue end-face combustion.

[0042] The lid 16 is positioned so as to be in contact with the upper surface of the holder 14. The lid 16 is formed in a flat plate shape. The lid 16 is formed to cover the combustion chamber of the holder 14 and also forms the ceiling surface of the combustion chamber. When viewed from above, the lid 16 is formed in a rectangular shape, with a length (depth) of 14.6 cm in the front-to-back direction and a length (width) of 10.2 cm in the left-to-right direction. The external dimensions of the lid 16 are the same as those of a so-called 3.5-inch standard hard disk drive. The lid 16 forms a flat plate. The lid 16 is made of stainless steel metal. Screw holes are formed near the four corners of the lid 16, and screws are inserted into each of them, passing through the holder 14 and fastening it to the base body 12, firmly fastening the lid 16, holder 14, and base body 12 together. The thickness (height HA) of the structure assembled from these parts is approximately 26 mm. For example, if the goal is to completely disable the hard disk 50 by filling it with sufficient explosives 60, the thickness of the information leakage suppression device 1 is approximately 26 mm, which is the thickness of a single 3.5-inch standard hard disk drive.

[0043] In this configuration, the base body 12 with the hard disk 50 positioned inside, the holder 14, and the lid 16 combine to form a rectangular shape with a depth LA = 14.6 cm, a width WA = 10.2 cm, and a height HA = 2.6 cm, as shown in Figures 2, 3, and 4. Therefore, the length and width of this combination are the same as those of a 3.5-inch standard hard disk drive, and the height is approximately one time the height of a 3.5-inch standard hard disk drive. When viewed from above, the base body 12, the holder 14, and the lid 16 are formed to have a common rectangular outer shape. Thus, these four components are combined to form a single rectangular box component. As a result, the information leakage suppression device 1 can be easily placed inside the personal computer 2, and the information leakage suppression device 1 is formed in a simple shape that is easy for the user to handle.

[0044] The information leakage suppression device 1 further includes an ignition device 22 for igniting the explosive 60, a second power supply device 24, and an operating device 30.

[0045] The second power supply unit 24 supplies power to the ignition device 22 and the actuator 30 independently, separate from the first power supply unit 7 of the personal computer 2 which supplies power to the hard disk 50. The second power supply unit 24 is located inside the case 3. The second power supply unit 24 can be made up of, for example, dry cell batteries or a battery. Therefore, even if the power to the personal computer 2 is disconnected, the second power supply unit 24 can operate the ignition device 22 using a separate power supply. The second power supply unit 24 may be located in the space within the information leakage suppression device 1. The second power supply unit 24 is electrically connected to the ignition device 22 and the actuator 30, etc. The second power supply unit 24 may also be electrically connected to the first power supply unit 7 for charging functions, etc.

[0046] The actuator 30 includes, for example, a wire loop sensor. When the loop circuit of the wire 32 of the actuator 30 is cut or broken, the detection unit detects that the circuit has been cut and transmits an activation signal to the ignition device 22. As a result, for example, if someone tries to take away the personal computer 2 along with the case 3, the loop circuit of the actuator 30 will be cut and the ignition device 22 will activate immediately. Alternatively, for example, if someone tries to remove the information leakage suppression device 1 from the drive inside the case 3 without following the procedure and take it away, the loop circuit of the actuator 30 may be cut and the ignition device 22 may activate immediately. The actuator 30 is located inside the case 3, and the loop circuit of its wire 32 is configured to return to the inside of the case 3 via a component outside the case 3. Furthermore, the actuator 30 may be equipped with a wireless communication unit capable of wireless communication, and may determine the operation of the ignition device 22 by receiving a predetermined activation signal from an external source, and transmit the activation signal to the ignition device 22. This makes it possible for an administrator to activate the ignition device 22 from a remote location to prevent information leakage.

[0047] The ignition device 22 is configured to ignite the gunpowder 60 in the hub combustion chamber 40 and initiate combustion of the gunpowder. The ignition device 22 is formed near the inlet of the hub combustion chamber 40. The ignition device 22 includes a heating section 22a, for example, made of wound nichrome wire. The ignition device 22 is connected to a second power supply unit 24 that supplies power to the ignition device 22 independently. The ignition device 22 is connected to the second power supply unit 24 via a power line 22b. In Figure 1, the power line 22b is shown by a dashed line. The ignition device 22 is operated by a command from the actuator 30, and the nichrome wire is heated by energizing the heating section 22a, reaching a high temperature, for example, about 300 to 400 degrees Celsius, which ignites the gunpowder 60. The ignition device 22 can ignite the gunpowder 60 in the hub combustion chamber 40 by a command from the actuator 30. As a variation, the ignition device 22 may use an ignition bulb, which is ignited by applying current to it, and the gunpowder 60 is ignited by the ignition bulb.

[0048] The actuator 30 has a function that can control the ignition of the ignition device 22, for example. When the ignition device 22 receives an activation command, it starts supplying power to the heating unit 22a for igniting the gunpowder 60. When the ignition device 22 determines that it has not received an activation command, it is controlled not to supply power to the heating unit 22a. The actuator 30 may be located, for example, within the case 3, at a distance from the holder 14, etc. The ignition device 22 is electrically connected to the heating unit 22a and the second power supply unit 24. In addition, all or part of the ignition device 22 may be formed by a control unit such as the memory of the personal computer 2. The ignition device 22 incorporates a CPU 17 and a storage device 19 such as memory, and controls connected equipment to execute predetermined controls based on a predetermined control program recorded in the memory, etc. The ignition device 22 is electrically connected to the actuator 30, the second power supply unit 24, etc. These electrical connections may be made by wireless communication, etc. The ignition device 22 stores a program that allows it to execute an operating mode in which it starts supplying power to the heating unit 22a when it receives an operation command. The ignition device 22 also stores a program that allows it to execute a non-operating mode in which it does not start supplying power to the heating unit 22a when it does not receive an operation command.

[0049] Next, with reference to Figure 3, the manufacturing method and arrangement method of the information leakage suppression device 1 will be explained.

[0050] First, the base body 12, holder 14, and lid 16 of the information leakage suppression device 1 are prepared. Next, a so-called 2.5-inch hard disk 50 is placed in the recess 12a of the base body 12. The hard disk 50 is electrically connected to the motherboard 6 and configured to be used in the same way as a normal hard disk 50.

[0051] The holder 14 contains gunpowder 60 in the hub combustion chamber 40, the first combustion chamber 41, and the second combustion chamber 42. The heating element 22a of the ignition device 22 is located at the inlet of the hub combustion chamber 40. The ignition device 22 is connected to the heating element 22a via a power line 22b.

[0052] The information leakage suppression device 1 is arranged in the area of ​​one 3.5-inch drive bay 9.

[0053] The wires 32 of the actuator 30 are wired to the appropriate location, and the ignition device 22 is put into standby mode.

[0054] Next, with reference to Figures 4, 6, 10, and 11, the operation of the information leakage suppression device 1 in disabling the use of platters in the hard disk 50 will be explained.

[0055] First, as shown in Figure 11, at time T0, the ignition device 22 of the information leakage suppression device 1 starts heating the gunpowder 60 in the hub combustion chamber 40. The gunpowder 60 in the hub combustion chamber 40 starts burning from time T1.

[0056] When the gunpowder 60 in the hub combustion chamber 40 etc. begins to burn, the gunpowder 60 in the hub combustion chamber 40 etc. begins end-face combustion, and flames and combustion gases are blown out through the nozzle section 21. The combustion gases are rapidly narrowed and accelerated at the nozzle section 21. The combustion gases are ejected from the nozzle section 21 at a relatively high speed and temperature toward the hard disk case 56, and the iron plate of the flat plate 56e (see Figure 4) on the upper surface of the hard disk case 56 is heated to a high temperature of, for example, about 2000 degrees, and a first opening 56f is formed by the blast of the combustion gases. For example, the opening formed in the flat plate 56e is a circular opening and is the same size as the nozzle section 21. The gunpowder 60 in the combustion chamber etc. continues to burn even after the first opening 56f is formed in the flat plate 56e.

[0057] Figure 12 shows a schematic illustration of the inside of the hard disk 50 in a top view, illustrating the positional relationship between the platter 53 and the nozzle section 21 of the hard disk 50. The position of the nozzle section 21 is illustrated by a dashed line. Note that the position of the nozzle section 21 can be changed to any position, and the number of nozzle sections 21 can also be changed. To clearly show the relationship between the platter 53 and the nozzle section 21, the illustration of components other than the actuator 54 of the hard disk 50 has been omitted. A flame induction region 70 extends into the hard disk from a first opening 56f formed by combustion gases from the nozzle section 21. The flame induction region 70 is formed to spread concentrically from the first opening 56f, as shown by arrow F1. The flame induction region 70 is a region set within the hard disk 50. The flame induction region 70 indicates, for example, the main path through which the flame and the main flow of high-temperature combustion gases pass. The flame induction region 70 is formed so that the flame of the gunpowder and the main stream of the high-temperature combustion gas flow blown in from the first opening 56f spread out from the first opening 56f. The flame induction region 70 is illustrated, for example, by a dashed line in Figure 12. The course of the flame induction region 70 can be changed under various conditions.

[0058] Because the first area A1 (see Figure 7) of the inner opening of the nozzle section 21 is smaller than the second area A2 (B1 + B2) of the combustion surface of the hub combustion chamber 40, the combustion gas flow path from the hub combustion chamber 40 to the nozzle section 21 is narrowed, and the combustion gas flowing from the hub combustion chamber 40 to the nozzle section is accelerated. The accelerated combustion gas makes it easier to widen the area of ​​the platter 53's memory area that is easily rendered unusable by the flame and the main flow of high-temperature combustion gas. By setting the flame induction area 70 relatively wide or long on the platter 53, a wide area can be efficiently rendered unusable. The flame induction area 70 is configured such that its width is the same as or slightly larger than the diameter of the first opening. This allows the width of the flame induction area 70 to be designed and planned according to the diameter of the first opening 56f. Thus, the area on the platter 53 to be rendered unusable can be planned.

[0059] In this way, the flame and the main stream of high-temperature combustion gas extending from the gunpowder 60 in the nozzle section 21 are guided along the flame induction region 70 as described above, and the heat can burn out the memory area of ​​the platter 53, rendering it unusable. The flame and the main stream of high-temperature combustion gas have a temperature of, for example, about 2000 degrees Celsius, and in areas relatively close to the flame and the main stream of high-temperature combustion gas, the likelihood of rendering the memory area of ​​the platter 53 unusable can be increased. Furthermore, even in areas relatively far from the flame and the main stream of high-temperature combustion gas, the likelihood of rendering the memory area of ​​the platter 53 unusable can be increased. For example, by running the flame and the main stream of high-temperature combustion gas over a relatively long distance near the surface of the platter 53, a relatively large area of ​​the platter 53 can be rendered unusable in a short time. Note that "unusable" means that the platter 53 is rendered unusable to the extent that it is impossible or requires considerable effort and time to repair it so that the information stored in it can be retrieved.

[0060] The main stream of flame and high-temperature combustion gas is guided along the flame induction region 70, but some of the branched flame and high-temperature combustion gas flows below and behind the platter 53. Although the branched flame and high-temperature combustion gas have lower heating performance than the main stream, they have the ability to render the memory area of ​​the platter 53 unusable. Therefore, the branched flame and high-temperature combustion gas flow below and behind the platter 53, making it easier to render not only the upper platter but also the lower platter unusable from the parts that have been heated by the flame and high-temperature combustion gas. The flame and combustion gas stream blown in from the first opening 56f is extremely hot and is blown into the hard disk 50 all at once, so even the branched flame and high-temperature combustion gas can render the memory area of ​​the platter 53 unusable due to heat. Therefore, even parts that are not directly hit by the main stream can be easily rendered unusable by the branched stream.

[0061] The combustion of the gunpowder 60 in the combustion chamber continues for a certain period of time from time T1 to time T2, and the flame and the main stream of high-temperature combustion gases also continue to flow for a certain period of time. When the combustion of the gunpowder 60 ends at time T2, the information leakage suppression operation by the information leakage suppression device 1 ends.

[0062] As described above, the information leakage suppression device 1 is not limited to the case in which flames are blown into the hard disk 50 only from the first opening 56f. As a modification, an information leakage suppression device 1 may be formed in which flames are blown in from other openings in addition to the first opening 56f. By blowing flames in from other openings in addition to the first opening 56f, the inside of the hard disk 50 is heated strongly around each opening, making it easier to render a wide area on the platter 53 unusable.

[0063] Next, the information leakage suppression device 101 according to the second embodiment of the present invention will be described with reference to Figures 14 to 16. The second embodiment is an example in which the combustion chamber of the information leakage suppression device 1 according to the present invention is formed in a different shape. Figure 14 is a top view of the holder of the information leakage suppression device according to the second embodiment of the present invention. Since the information leakage suppression device 101 according to the second embodiment is substantially the same in structure as the information leakage suppression device according to the first embodiment described above, only the differences between the second embodiment of the present invention and the first embodiment will be explained, and similar parts will be denoted by the same reference numerals in the drawings and their explanation will be omitted.

[0064] The holder 14 comprises a nozzle section 21, a hub combustion chamber 40, a first combustion chamber 41, a second combustion chamber 42, a third combustion chamber 43, and a fourth combustion chamber 44. For example, the central axis X1 of the nozzle section 21 is positioned perpendicular to the hard disk 50. In a top view, the central axis X1 of the nozzle section 21 is positioned offset from the spindle motor section 52 of the platter 53 of the hard disk 50. As a result, the combustion of gunpowder in the hub combustion chamber 40, the first combustion chamber 41, the second combustion chamber 42, the third combustion chamber 43, and the fourth combustion chamber 44 (hereinafter referred to as "combustion chambers, etc.") causes flames to enter the hard disk 50 at a position offset from the spindle motor section 52 of the platter, as shown by arrow D1 (see Figure 15), thereby efficiently rendering the stored data on the platter unusable. As will be described later, the width in the short-side direction of the first combustion chamber 41 and the second combustion chamber 42 in the second embodiment may be formed to be shorter than the width in the short-side direction of the first combustion chamber 41 and the second combustion chamber 42 in the first embodiment.

[0065] The third combustion chamber 43 extends from the hub combustion chamber 40 in a direction different from the first combustion chamber 41 and the second combustion chamber 42, and burns gunpowder inside. As will be described later, the third combustion chamber 43 has the function of increasing the combustion area in the initial stages of combustion, further accelerating the combustion gas ejected from the nozzle section 21 toward the hard disk 50, and improving the penetration force of the flame from the nozzle section 21 and the hole-forming force. The number and shape of such additional combustion chambers are arbitrary. For example, the holder 14 may include the nozzle section 21, the hub combustion chamber 40, the first combustion chamber 41, the second combustion chamber 42, and the third combustion chamber 43. That is, the fourth combustion chamber 44 may be omitted. As a variation, the hub combustion chamber 40 may be formed in a polygonal or circular shape when viewed from above, and three or more combustion chambers, for example, the third combustion chamber 43, the fourth combustion chamber 44, and the fifth combustion chamber, may be connected to the hub combustion chamber 40.

[0066] The third combustion chamber 43 extends perpendicular to the first combustion chamber 41, centered on the hub combustion chamber 40. The third combustion chamber 43 extends laterally from the hub combustion chamber 40. The third combustion chamber 43 is formed to extend linearly in the horizontal direction. The third inlet 43a of the third combustion chamber 43 is connected to the third opening 40c of the hub combustion chamber 40. The bottom surface of the third combustion chamber 43 is formed by a plane extending horizontally. The upper end of the third combustion chamber 43 is formed on the upper surface of the holder 14. The third combustion chamber 43 extends along the short side of the holder 14. In a top view, the third combustion chamber 43 forms a substantially rectangular groove. In a longitudinal cross-section, the third combustion chamber 43 is formed in a square shape, for example, a rectangular shape. The ratio of the height H3 of the third combustion chamber 43 to the longitudinal opening width W3 is a ratio within the range of 1:1 to 1:4, for example, a ratio within the range of 1:1.1 to 1:4, for example, 1:2. The length L3 of the third combustion chamber 43 in the depth direction (short side direction of the holder) is a length within the range of 5 mm to 20 mm. The length (width) W3 of the third combustion chamber 43 in the lateral direction (long side direction of the holder) is a length within the range of 5 mm to 20 mm. The height H3 of the third combustion chamber 43 is a height within the range of 3 mm to 10 mm. The central axis C3 of the third combustion chamber 43 in the depth direction is perpendicular to the central axis X1 of the nozzle section 21. The central axis C3 of the third combustion chamber 43 in the depth direction is the same as the central axis C4 of the fourth combustion chamber 44 in the depth direction. The size and shape of the third combustion chamber 43 are the same as those of the fourth combustion chamber 44. For example, the first volume E1 of the gunpowder 60 in the first combustion chamber 41 is the same as the second volume E2 of the gunpowder 60 in the second combustion chamber 42. The size and shape of the third combustion chamber 43 may differ from those of the fourth combustion chamber 44.

[0067] The depth L3 of the third combustion chamber 43 is shorter than the depth L1 of the first combustion chamber 41 and also shorter than the depth L2 of the second combustion chamber 42. Similarly, the depth L4 of the fourth combustion chamber 44 is shorter than the depth L1 of the first combustion chamber 41 and also shorter than the depth L2 of the second combustion chamber 42. This allows the combustion time of the third combustion chamber 43 and the fourth combustion chamber 44 to be shorter than that of the first combustion chamber 41 and the second combustion chamber 42. Therefore, the gunpowder 60 in the third combustion chamber 43 and the fourth combustion chamber 44 can be additionally burned in the initial stages of combustion, thereby relatively increasing the combustion area. Consequently, while combustion is taking place in the third combustion chamber 43 and the fourth combustion chamber 44, the combustion gas flowing into the nozzle section 21 from the combustion chambers is further accelerated, making it easier to form holes on the top surface of the hard disk 50.

[0068] The third combustion chamber 43 burns the gunpowder 60 placed inside. The gunpowder 60 is distributed throughout the third combustion chamber 43 for approximately its entirety. For example, the gunpowder 60 is distributed from the third inlet 43a of the third combustion chamber 43 to the end opposite the nozzle 21. The gunpowder 60 in the third combustion chamber 43 is formed to enable end-face combustion, which helps to maintain a generally constant combustion area. For example, the combustion area of ​​the gunpowder in the third combustion chamber 43 is equal to the cross-sectional area of ​​the longitudinal section of the third combustion chamber 43. The third combustion chamber 43 forms a rectangular third combustion surface B3. For example, the third combustion surface B3 corresponds to the longitudinal section of the third combustion chamber 43. The area of ​​the third combustion surface B3 corresponds to the combustion area of ​​the gunpowder in the third combustion chamber 43. The first area A1 of the inner opening of the nozzle section 21 is smaller than the second area A2 of the first combustion chamber 41, second combustion chamber 42, third combustion chamber 43, and fourth combustion chamber 44 (the sum up to the third combustion chamber 43 if there is no fourth combustion chamber 44). This configuration narrows the combustion gas flow path from the combustion chambers to the nozzle section 21, accelerating the combustion gas flowing into the nozzle section 21 from the combustion chambers and making it easier to form holes on the upper surface of the hard disk 50. The second area A2, which is the sum of the first combustion surface B1 and the second combustion surface B2, is, for example, 100 mm². 2The area can be such that... In contrast, the second area A2, which is the sum of the first combustion surface B1, the second combustion surface B2, the third combustion surface B3, and the fourth combustion surface B4, can be, for example, 150 mm². 2 The area can be such that the combustion area of ​​the third combustion chamber 43 is, for example, approximately 25 mm on the third combustion surface B3. 2 This is possible. As the combustion of the gunpowder progresses, the third combustion surface B3 moves away from the inlet of the third combustion surface B3. Although the third combustion surface B3 moves, the combustion area of ​​the third combustion surface B3 remains almost constant. The third combustion surface B3 is formed in a direction perpendicular to the inner and outer openings of the nozzle portion 21. The direction of combustion of the gunpowder within the third combustion surface B3, for example, the direction of movement of the third combustion surface B3, is different from the direction in which the nozzle portion 21 extends.

[0069] The fourth combustion chamber 44 extends from the hub combustion chamber 40 in a direction different from the first combustion chamber 41, the second combustion chamber 42, and the third combustion chamber 43, and burns gunpowder inside. As will be described later, the fourth combustion chamber 44 has the function of increasing the combustion area in the initial stages of combustion, further accelerating the combustion gas ejected from the nozzle section 21 toward the hard disk 50, and improving the penetration force of the flame from the nozzle section 21 and the hole-forming force. As mentioned above, the number and shape of such additional combustion chambers are arbitrary.

[0070] The fourth combustion chamber 44 extends perpendicular to the first combustion chamber 41, centered on the hub combustion chamber 40. The fourth combustion chamber 44 extends opposite the third combustion chamber 43, centered on the hub combustion chamber 40. Note that any of the first to fourth combustion chambers 41 to 44 can be formed in any orientation. The fourth combustion chamber 44 extends laterally from the hub combustion chamber 40. The fourth combustion chamber 44 is formed to extend linearly in the horizontal direction. The fourth inlet 44a of the fourth combustion chamber 44 is connected to the fourth opening 40d of the hub combustion chamber 40. The bottom surface of the fourth combustion chamber 44 is formed by a plane extending horizontally. The upper end of the fourth combustion chamber 44 is formed on the upper surface of the holder 14. The fourth combustion chamber 44 extends along the short side of the holder 14. In a top view, the fourth combustion chamber 44 forms a roughly rectangular groove. The fourth combustion chamber 44 is formed in a rectangular shape, for example, a square shape, in its longitudinal cross-section. The ratio of the height H4 of the fourth combustion chamber 44 to the longitudinal opening width W4 is a ratio within the range of 1:1 to 1:4, for example, a ratio within the range of 1:1.1 to 1:4, for example, 1:2. The length L4 of the fourth combustion chamber 44 in the depth direction (short side direction of the holder) is a length within the range of 5 mm to 20 mm. The length (width) W4 of the fourth combustion chamber 44 in the lateral direction (long side direction of the holder) is a length within the range of 5 mm to 20 mm. The height H4 of the fourth combustion chamber 44 is a height within the range of 3 mm to 10 mm. The central axis C4 of the fourth combustion chamber 44 in the depth direction is perpendicular to the central axis X1 of the nozzle section 21. The size and shape of the fourth combustion chamber 44 are the same as those of the third combustion chamber 43. For example, the third capacity E3 of the third combustion chamber 43 is the same as the fourth capacity E4 of the fourth combustion chamber 44. The size and shape of the third combustion chamber 43 may differ from those of the fourth combustion chamber 44.

[0071] The fourth combustion chamber 44 burns the gunpowder 60 placed inside. The gunpowder 60 is distributed throughout the fourth combustion chamber 44 for approximately its entirety. For example, the gunpowder 60 is distributed in the fourth combustion chamber 44 from the fourth inlet 44a to the end opposite the nozzle 21. The gunpowder 60 in the fourth combustion chamber 44 is formed to enable end-face combustion. For example, the combustion area of ​​the gunpowder in the fourth combustion chamber 44 is equal to the cross-sectional area of ​​the longitudinal section of the fourth combustion chamber 44. The fourth combustion chamber 44 forms a rectangular fourth combustion surface B4. For example, the fourth combustion surface B4 corresponds to the longitudinal section of the fourth combustion chamber 44. The area of ​​the fourth combustion surface B4 corresponds to the combustion area of ​​the gunpowder in the fourth combustion chamber 44. The first area A1 of the inner opening of the nozzle section 21 is smaller than the second area A2 of the first combustion chamber 41, second combustion chamber 42, third combustion chamber 43, and fourth combustion chamber 44. This configuration narrows the combustion gas flow path from the combustion chambers to the nozzle section 21, accelerating the combustion gas flowing into the nozzle section 21 from the combustion chambers and making it easier to form holes on the upper surface of the hard disk 50. The second area A2, which is the sum of the first combustion surface B1 and the second combustion surface B2, is, for example, 100 mm². 2 The area can be such that... In contrast, the second area A2, which is the sum of the first combustion surface B1, the second combustion surface B2, the third combustion surface B3, and the fourth combustion surface B4, can be, for example, 150 mm². 2 The area can be such that... Also, for example, the second area A2, which is the sum of the first combustion surface B1 and the second combustion surface B2, can be, for example, 50 mm 2 The area can be such that the total area A2 of the first combustion surface B1, second combustion surface B2, third combustion surface B3, and fourth combustion surface B4 is, for example, 100 mm². 2 The area can be such that the combustion area of ​​the fourth combustion chamber 44 is, for example, approximately 25 mm on the fourth combustion surface B4. 2 This can be achieved. As the combustion of the gunpowder progresses, the fourth combustion surface B4 moves away from the inlet of the fourth combustion surface B4. Although the fourth combustion surface B4 moves, the combustion area of ​​the fourth combustion surface B4 remains almost constant. The fourth combustion surface B4 is oriented perpendicular to the inner and outer openings of the nozzle section 21. The direction of combustion of the gunpowder within the fourth combustion surface B4, for example, the direction of movement of the fourth combustion surface B4, is different from the direction in which the nozzle section 21 extends.

[0072] The total second area A2 of the first combustion surface B1, second combustion surface B2, third combustion surface B3, and fourth combustion surface B4 may be set to an area within the range of 2 to 4 times the first area A1 of the inner opening 21a of the nozzle section 21. By setting the total second area A2 of the first combustion surface B1, second combustion surface B2, third combustion surface B3, and fourth combustion surface B4 to a predetermined multiple of the first area A1 of the inner opening 21a of the nozzle section 21, the ratio to which the combustion gas flow path from the first combustion chamber 41, second combustion chamber 42, third combustion chamber 43, and fourth combustion chamber 44 to the nozzle section 21 is narrowed can be adjusted. For example, it can be adjusted to suppress the degree to which the combustion gas flowing into the nozzle section 21 from the combustion chamber, etc. is accelerated or to suppress the risk of combustion gas choking. In this way, by considering the total area of ​​the first combustion surface B1, the second combustion surface B2, the third combustion surface B3, and the fourth combustion surface B4, the degree of freedom for the individual shapes of the first to fourth combustion chambers 41 to 44 can be improved. For example, the first to fourth combustion chambers 41 to 44 can be formed into relatively low rectangular shapes. By considering the second area A2, which is the total area of ​​the combustion surfaces of the first to fourth combustion chambers 41 to 44, the height of each can be suppressed while also suppressing the individual widths. For example, if the second area A2 is 100 mm 2 If you want to achieve a specific area, and you want to adjust it using only the area of ​​a single combustion chamber, and you want the height of the combustion chamber to be 5mm, then the width of the combustion chamber must be 20mm, requiring the formation of a wide combustion chamber. In this way, if the ratio of the height to the width of the combustion chamber is 1:4, not only does it become more difficult to construct the combustion chamber, but the gunpowder is more likely to cool during combustion, potentially leading to unstable combustion such as combustion stopping. In contrast, for example, if combustion is performed using multiple combustion chambers, such as the first combustion chamber 41 to the fourth combustion chamber 44, if you want the height of each combustion chamber to be 5mm, then the width of each combustion chamber must be 5mm, and the area of ​​each combustion surface must be 25mm. 2 As the area of ​​the second area A2, 100mm 2The area can be set to this. If the relationship between the height and width of the combustion chamber is within a predetermined range, such as between 1:1 and 1:3, it becomes easier to construct the combustion chamber, and the risk of combustion stopping due to the gunpowder being cooled by the metal plate during combustion is reduced, making it easier to continue combustion. In addition, the height of the first to fourth combustion chambers 41 to 44 can be suppressed to realize a second area A2 total for the first to fourth combustion chambers 41 to 44. Furthermore, it is possible to achieve efficient throttling of the combustion gas flow path from the first to fourth combustion chambers 41 to 44 to the nozzle section 21, as well as improve the ease of constructing the first to fourth combustion chambers 44, and reduce the risk of combustion gas choking at the throttling of the combustion gas flow path.

[0073] By considering the total area of ​​the first combustion surface B1, the second combustion surface B2, the third combustion surface B3, and the fourth combustion surface B4, the degree of freedom for the individual shapes of the first to fourth combustion chambers 41 to 44 can be increased. For example, if the second area A2 is 100 mm² 2 If you want the area to be 25mm, set the first combustion surface B1 to 25mm 2 , the second combustion surface B2 is 25 mm 2 , the third combustion surface B3 is 25 mm 2 And the fourth combustion surface B4 is 25 mm 2 This arrangement may also be used. For example, in the relatively early stages of combustion, when combustion is occurring not only on the first combustion surface B1 and the second combustion surface B2 but also on the third combustion surface B3 and the fourth combustion surface B4, the total combustion area of ​​the combustion surfaces can be made relatively large, and after the combustion of the third combustion surface B3 and the fourth combustion surface B4 is completed, only the combustion of the first combustion surface B1 and the second combustion surface B2 occurs. By arranging it in this way, the amount of gunpowder 60 used in the later stages of combustion, after a hole has been made in the top surface of the hard disk 50, can be reduced. For example, the combustion surfaces of the first combustion chamber 41 and the second combustion chamber 42 can be made relatively small. For example, the height of the combustion chambers of the first combustion chamber 41 and the second combustion chamber 42 can be 5 mm, the width of each combustion chamber can be 5 mm, and the area of ​​each combustion surface can be 25 mm 2The area can be set to the above. As described above, the cross-sectional shape of the first combustion chamber 41 to the fourth combustion chamber 44 can be freely changed. For example, when a third combustion chamber 43 is provided, the third area A3 (sum of B1 and B2), which is the sum of the first combustion surface B1 of the first combustion chamber 41 and the second combustion surface B2 of the second combustion chamber 42, can be made smaller than the second area A2 (sum of B1 to B4). This makes it possible to suppress the combustion area and reduce the amount of explosive used in the combustion of the first combustion surface B1 and the second combustion surface B2 in the latter half of the combustion period. It also makes it easier to efficiently render the information on the hard disk unusable.

[0074] Examples of embodiments of the present invention may be provided in the following forms.

[0075] (1) An information leakage suppression device for suppressing the leakage of information from a hard disk, comprising: a base body on which the hard disk is placed on the inner upper surface; a holder placed in contact with the upper surface of the hard disk, the holder having a nozzle portion opening toward the upper surface of the hard disk, a hub combustion chamber connected to the nozzle portion and burning explosives inside, a first combustion chamber extending from the hub combustion chamber and burning explosives inside, and a second combustion chamber extending from the hub combustion chamber in a direction different from the first combustion chamber and burning explosives inside; and a lid portion placed in contact with the upper surface of the holder and formed in the shape of a flat plate.

[0076] (2) The information leakage suppression device according to (1), wherein the hub combustion chamber is located above the nozzle portion, the first combustion chamber extends laterally from the hub combustion chamber, and the second combustion chamber extends laterally from the hub combustion chamber.

[0077] (3) The second combustion chamber is the information leakage suppression device described in (1), which extends in a direction opposite to the first combustion chamber with respect to the hub combustion chamber.

[0078] (4) The information leakage suppression device according to (1), wherein the second area, which is the sum of the first combustion surface of the first combustion chamber and the second combustion surface of the second combustion chamber, is an area within the range of 2 to 4 times the first area of ​​the inner opening of the nozzle portion.

[0079] (5) The information leakage suppression device according to (1), wherein the second area, which is the sum of the first combustion surface of the first combustion chamber and the second combustion surface of the second combustion chamber, is three times the area of ​​the first area of ​​the inner opening of the nozzle portion.

[0080] (6) The information leakage suppression device according to (4), wherein the first combustion surface and the second combustion surface are set to proportionally divide the second area, the first combustion chamber is formed to have a proportionally divided first combustion surface, and the second combustion chamber is formed to have a proportionally divided second combustion surface.

[0081] (7) The information leakage suppression device according to (4), wherein the first combustion surface and the second combustion surface are set so as to divide the second area in half, the first combustion chamber is formed to have the first combustion surface divided in half, and the second combustion chamber is formed to have the second combustion surface of the same size as the first combustion surface.

[0082] (8) The information leakage suppression device according to (1), wherein the first combustion chamber has a rectangular cross-section, and the ratio of its vertical length to its horizontal length is in the range of 1:1 to 1:3, and the second combustion chamber has a rectangular cross-section, and the ratio of its vertical length to its horizontal length is in the range of 1:1 to 1:3.

[0083] (9) The information leakage suppression device according to (1), further comprising a third combustion chamber extending from the hub combustion chamber in a direction different from that of the first and second combustion chambers, wherein the depth of the third combustion chamber is shorter than the depth of the first combustion chamber and shorter than the depth of the two combustion chambers.

[0084] (10) The information leakage suppression device according to (9), wherein the sum of the third area of ​​the first combustion surface of the first combustion chamber and the second combustion surface of the second combustion chamber, when the third combustion chamber is provided, is smaller than the second area.

[0085] The embodiments for carrying out the present invention are not limited to those described above, and further variations can be applied. Various alternative embodiments and examples will be apparent to those skilled in the art based on the disclosed technology.

[0086] Furthermore, in this embodiment, for example, the holder 14 has one nozzle section 21 and one combustion chamber 40, but as a modification, the holder 14 may have multiple nozzle sections 21 and combustion chambers 40. For example, the holder 14 may have a first nozzle section and a first combustion chamber connected thereto, as well as a second nozzle section and a second combustion chamber connected thereto. When the holder 14 has multiple nozzle sections in this way, the flame induction region 70 may form a flame induction region that extends linearly on the platter 53 in the hard disk 50 from a first opening 56f to another second opening. This makes it easier to set the position where the main flow of the flame and combustion gases extends. Also, the main flow of the flame and combustion gases can be set to extend between the two openings, making it easier to smoothly guide the main flow of the flame and combustion gases. [Explanation of Symbols]

[0087] 1: Information leakage control device 12: Base body 14: Holder 16: Lid 21: Nozzle part 21a:Inner opening 40: Hub combustion chamber 41: First combustion chamber 42: Second combustion chamber 50: Hard disk 50a:Top surface 60: Gunpowder 101: Information leakage control device

Claims

1. A device for suppressing information leakage from hard disks, A base body on which the aforementioned hard disk is positioned on the inner upper surface, A holder positioned so as to be in contact with the upper surface of the hard disk, comprising a nozzle portion that opens toward the upper surface of the hard disk, A hub combustion chamber connected to the nozzle section and which burns gunpowder inside, A first combustion chamber extends from the aforementioned hub combustion chamber and burns gunpowder inside, The holder comprises a second combustion chamber that extends from the hub combustion chamber in a direction different from the first combustion chamber and burns gunpowder inside, An information leakage suppression device comprising a lid portion that is positioned in contact with the upper surface of the holder and is formed in a flat plate shape.

2. The hub combustion chamber is positioned above the nozzle section. The first combustion chamber extends laterally from the hub combustion chamber, The information leakage suppression device according to claim 1, wherein the second combustion chamber extends laterally from the hub combustion chamber.

3. The information leakage suppression device according to claim 1, wherein the second combustion chamber extends in a direction opposite to the first combustion chamber, with the hub combustion chamber as the center.

4. The information leakage suppression device according to claim 1, wherein the sum of the second area of ​​the first combustion surface of the first combustion chamber and the second combustion surface of the second combustion chamber is an area within the range of 2 to 4 times the first area of ​​the inner opening of the nozzle portion.

5. The information leakage suppression device according to claim 1, wherein the sum of the second area of ​​the first combustion surface of the first combustion chamber and the second combustion surface of the second combustion chamber is three times the area of ​​the first inner opening of the nozzle portion.

6. The first combustion surface and the second combustion surface are set so as to proportionally divide the second area. The first combustion chamber is formed to have a proportionally divided first combustion surface, The information leakage suppression device according to claim 4, wherein the second combustion chamber is formed to have a proportionally allocated second combustion surface.

7. The first combustion surface and the second combustion surface are set such that the second area is divided in half. The first combustion chamber is formed to have a first combustion surface that is divided in half, The information leakage suppression device according to claim 4, wherein the second combustion chamber is formed to have a second combustion surface of the same size as the first combustion surface.

8. The first combustion chamber has a rectangular cross-section, and the ratio of its length to its width is within the range of 1:1 to 1:

3. The information leakage suppression device according to claim 1, wherein the second combustion chamber has a rectangular vertical cross-section, and the ratio of its vertical length to its horizontal length is within the range of 1:1 to 1:

3.

9. The hub combustion chamber comprises a third combustion chamber extending in a direction different from that of the first and second combustion chambers, The information leakage suppression device according to claim 1, wherein the depth of the third combustion chamber is shorter than the depth of the first combustion chamber and shorter than the depth of the second combustion chamber.

10. The information leakage suppression device according to claim 9, wherein, when the third combustion chamber is provided, the sum of the third area of ​​the first combustion surface of the first combustion chamber and the second combustion surface of the second combustion chamber is smaller than the second area.

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