JP2006240531A - Parachute - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parachute with a high drag coefficient and good stability. <P>SOLUTION: This parachute includes a canopy 1 which becomes almost hemispheric upon inflation. The canopy 1 is equipped with a canopy skirt part 12 constituting a hemispheric open surface, a canopy top part 11 forming the top, and a canopy central part 13 connecting the canopy skirt part 12 to the canopy top part 11. The canopy central part 13 is circumferentially mounted with a plurality of pockets 14 open to an open surface direction. Preferably the pockets 14 are provided around the circumference of the center of gravity G of the canopy 1. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a parachute, and more particularly to a parachute that can be lowered stably.

  Since the parachute composed of the hemispherical umbrella 1 has a large resistance coefficient, the parachute area required for lowering the fallen object at a certain speed or less can be reduced, and the fallen object dropped from the flying object or the flying object can be reduced. Widely used for lowering.

  As shown in FIG. 4, such a parachute includes an umbrella top 11 that forms the top of the hemispherical umbrella 1, an umbrella edge 12 that forms an open surface, and an umbrella that connects the umbrella top 11 and the umbrella edge 12. It has a central portion 13. The suspension rope 3 that supports the suspended object 2 to be decelerated and lowered is connected to the umbrella edge portion 12.

  When the parachute is extended and lowered, the flow is separated in the vicinity of the umbrella edge 12 of the umbrella 1, thereby generating an irregular flow (wake) with a vortex (see FIG. 4). Since the distance between the wake area and the umbrella body 1 is small, the pressure resistance from the wake area is exerted on the umbrella body 1, and there is a drawback that the oscillating movement occurs while the parachute is lowered, and it is difficult to stably descend. .

  In order to solve such a problem, as shown in FIGS. 5 and 6, as shown in FIGS. 5 and 6, a slit 5 is provided in the umbrella rim 12 or the extension 4 of the hemispherical umbrella, and air is injected outward to increase the pressure. The resistance is decreased (see the arrow in FIG. 6), the swing is suppressed, and the posture is stabilized (Japanese Patent No. 2743171). In addition, the extension part 4 is a part extended from the hemispherical umbrella 1 to the lower hemisphere part. Therefore, the extension part 4 has a shape curved inward and contributes to a stable descent of the parachute.

  In general, in order to improve the stability of the parachute, it can be achieved by reducing the resistance coefficient of the parachute. However, if the resistance coefficient is reduced, the descending speed increases, so the umbrella body 1 needs to be enlarged. There is. However, the storage capacity of the parachute is limited and cannot be generally increased in size. That is, a parachute having a large resistance coefficient and good stability is desired.

Since the parachute of the above-mentioned Japanese Patent No. 2743171 is provided with the slit 5, it is considered that the resistance coefficient becomes small and the stability of the parachute is improved. However, as will be apparent from the examples described later, in practice, this parachute is effective for the quick opening of the umbrella edge 12 of the umbrella 1 but does not contribute much to stability. Became clear.
Japanese Patent No. 2743171 JP 2002-12799 A

  An object of the present invention is to solve the above-described problems, that is, to provide a parachute having a large resistance coefficient and good stability.

  In order to solve the above-described problems, a parachute according to the present invention includes an umbrella body that is substantially hemispherical when extended, and the umbrella body forms an umbrella edge portion that forms a hemispherical open surface and a top portion of the umbrella body. A parachute comprising an umbrella top part and an umbrella center part for connecting the umbrella edge part and the umbrella top part, wherein a plurality of pockets opened in the opening surface direction are provided in the umbrella center part in the circumferential direction. To do.

  According to the present invention, since the pocket opened in the opening surface direction is provided in the circumferential direction in the central portion of the umbrella, when the parachute swings and tilts, the air that has entered the pocket corrects the tilt. It will load a drag in the direction. For this reason, the swing of the parachute is suppressed, and it is possible to descend stably. In addition, the resistance coefficient is not lowered to improve the stability, but rather the pocket is improved, and the characteristics as a parachute are remarkably improved.

  FIG. 1 is a side view of a parachute according to an embodiment of the present invention, and FIG. 2 is a plan view of the parachute of the present invention. As is clear from these figures, the parachute includes a plurality of substantially triangular gores 1a. It has a structure in which an umbrella body 1 which is sewn and connected and formed in a hemispherical shape and a suspension rope 3 is connected to the umbrella edge portion 12 of the umbrella body 1 or the aforementioned extension portion 4 (in this embodiment, the extension portion). 4).

  The umbrella 1 includes an umbrella top 11 that forms a hemispherical top, an umbrella edge 12 that forms an opening surface A (see FIG. 3A), and an umbrella that connects the umbrella edge 12 and the umbrella top 11. A central portion 13 is provided, and a plurality of pockets 14 are provided at the position of the umbrella central portion 13 in the circumferential direction of the umbrella body 1. The pocket 14 opens downward (and thus opens in the direction of the opening surface A of the umbrella), and can receive air drag during descending.

  FIG. 3 is a cross-sectional view of the umbrella. However, the extension is omitted. As shown in FIG. 3 (b), when the parachute swings and tilts, air strongly enters the tilted pocket 14 and the drag force of air acts strongly (see the arrow), on the other hand. The side pocket 14 'hardly receives air, so the action of air drag is small. For this reason, the umbrella body 1 rotates about the center of gravity G as a rotation axis by the drag force of the air in the pocket 14, and a force for correcting the umbrella body 1 to be vertical acts. For this reason, by providing the pocket 14 in the circumferential direction of the umbrella central portion 13 of the umbrella body 1, a force that suppresses swinging in all directions acts. In order to suppress the swinging by the drag force of air in this way, the position of the pocket 14 is preferably near the circumferential position of the center of gravity G of the hemispherical umbrella body 1. 12 is preferably provided in the circumferential direction in the vicinity of 12 (see FIG. 3A).

  The surface distance l between the opening 141 of the pocket 14 and the top of the umbrella 1 at the top of the umbrella 11 is the surface of the umbrella 1 from the top of the top 11 to the end of the umbrella edge 12 (opening surface A). When the distance is L, it is preferably 0.6L to 0.85L. If it deviates from the range of l = 0.6L to 0.85L, it will deviate significantly from the gravity center position G of the umbrella 1, and the action of air drag may be reduced, and the swing of the parachute may not be suppressed well. is there.

  In this embodiment, the pocket 14 has a structure in which one gore pocket 14 provided in one (1 gore) of the gore 1a and a pocket 14 (2 gore pockets) extending over two gores are alternately formed. However, the present invention is not limited to this, and it may be provided for every 1 gore or for every 2 gores. You may make it provide the gore 6 which does not form a pocket in the pocket of said 1 gore and the said 2 gore. That is, one gore pocket may be provided to provide the one gore pocket or the two gore pockets.

  In one embodiment of the present invention, the stability of the descent can be improved by adjusting the air permeability of the portion of the umbrella body 1. That is, a fabric that normally transmits air to the umbrella top portion 11, a fabric that does not easily transmit air to the umbrella edge portion 12, and a fabric that easily transmits air to the umbrella central portion 13 are used. The air permeability is preferably 1.4 to 1.6 at the umbrella center and 0 to 0.2 at the umbrella edge, where the air permeability (umbrella top) of a normal parachute is 1.

  By using a cloth that does not easily transmit air to the umbrella rim 12, the pressure inside the umbrella 1 is increased and the internal pressure of the umbrella 1 is increased to increase the projected area (opening surface A). , Can improve the drag. In addition, the use of the fabric described above for the umbrella edge 12 improves the air flow and quickly opens the umbrella, so that the action of the pocket 14 can be enjoyed quickly and the stability is also improved. To do.

  By using a cloth that allows air to permeate as usual at the top 11 of the umbrella, it is possible to suppress an increase in impact at the time of opening the umbrella and contribute to an improvement in stability. By using a cloth having a large air permeability for the umbrella central portion 13, the drag can be reduced without affecting the impact when the umbrella is opened, and the stability of the parachute can be improved.

  It is preferable that the area ratio of the umbrella edge part: umbrella central part: umbrella top part is 50 to 70%: 10 to 40%: 10 to 30%. It is because there exists a possibility that the above-mentioned fall cannot be exhibited if it deviates from these ranges.

  The pocket opening comes at a position 70% (l = 0.7 L) from the top of the umbrella top 11 at a distance L (see FIG. 3 (a)) from the top of the umbrella top 11 to the end of the umbrella edge 12. Thus, the parachute as shown in FIG. 1 was manufactured. In other words, the pocket 14 formed over one gore and the pocket formed over two gores were alternately formed side by side in the circumferential direction of the umbrella central portion 13 (Example 1). Similarly, one gore pocket 14 formed side by side in the circumferential direction of the umbrella central portion 13 at the same position (Example 2), two pockets 14 formed over the gore formed in the umbrella central portion 13 Prepared (Example 3).

  As a comparative example, a parachute provided with slits 5 in each gore 1a in the umbrella edge portion 12 as shown in FIGS. 5 and 6 was used (Comparative Example 2). Further, a normal parachute (Comparative Example 1) having no pockets or slits in the circumferential direction of the umbrella 1 as shown in FIG. 4 was prepared.

  The drag (average resistance coefficient) and swing angle when these parachutes were lowered were measured. The results are shown in FIG.

  From the results of FIG. 7, it can be seen that the parachute according to the present invention has an average resistance coefficient equal to or greater than that of Comparative Example 1 which is a normal parachute, and the swing angle is remarkably small. In addition, the parachute of Comparative Example 2 was found to have a greater swing angle than that of Comparative Example 1.

(Reference example)
A parachute having the structure shown in FIG. 4 having an area of an umbrella top portion of 20%, an umbrella central portion of 25%, and an umbrella edge portion of 60% was manufactured. In this case, when the air permeability at the top of the umbrella was 1 (normal air permeability), the air permeability at the center of the umbrella was 1.5, and the air permeability at the edge of the umbrella was 0.1. For comparison, the parachute shown in FIG. 4 is manufactured from those having an umbrella cloth of 1.5 (high air permeability), 1.0 (normal air permeability), and 0.1 (low air permeability). Then, the drag force (average resistance coefficient) and swing angle were measured when the parachute was lowered as in the example. The results are shown in FIG.

  According to this, the parachute of the reference example shows an average resistance coefficient similar to that of a parachute manufactured with an umbrella cloth having a small air permeability, and the swing angle is the smallest. That is, it was found that the stability was good.

  According to the present invention, since the pocket opened in the opening surface direction is provided in the circumferential direction in the central portion of the umbrella, when the parachute swings and tilts, the air that has entered the pocket corrects the tilt. It will load a drag in the direction. For this reason, the swing of the parachute is suppressed, and it is possible to descend stably. In addition, the resistance coefficient is not lowered to improve the stability, but rather the pocket is improved, and the characteristics as a parachute are remarkably improved.

The side view of one Embodiment of this invention. The top view of the said embodiment. Sectional drawing of the said embodiment. Explanatory drawing of the conventional parachute. The side view of the other type | formula parachute of the past. Sectional drawing of the said conventional parachute. The figure which shows the average air resistance coefficient and swing angle of the parachute of this invention. The figure which shows the average air resistance coefficient and swing angle of the parachute of a reference example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Umbrella 11 Umbrella top part 12 Umbrella edge part 13 Umbrella center part 14 Pocket 141 Pocket opening part 2 Suspension thing 3 Suspension rope 4 Extension part 5 Slit

Claims (10)

An umbrella body that is substantially hemispherical when extended, the umbrella body includes an umbrella edge portion that forms a hemispherical open surface, an umbrella top portion that forms a top portion of the umbrella body, the umbrella edge portion, and the umbrella top portion A parachute comprising an umbrella central part to be connected, wherein a plurality of pockets opened in the circumferential direction are provided in the umbrella central part in the circumferential direction. The parachute according to claim 1, wherein the pocket is provided in the vicinity of a circumferential position of the center of gravity of the umbrella. The surface distance l between the opening of the pocket and the top of the umbrella is 0.6 L, where L is the surface distance of the umbrella from the top of the umbrella to the end of the umbrella edge. The parachute according to claim 2, which is ˜0.85 L. The umbrella body is formed by connecting a plurality of substantially triangular gores, and the pocket has one gore pocket formed in a single gore and two gore pockets provided over two gores, 4. The parachute according to claim 1, wherein one gore pocket and two gore pockets are alternately formed. 4. The parachute according to claim 1, wherein the umbrella body is formed by connecting a plurality of substantially triangular gores, and the pocket is formed by a single gore pocket formed in a single gore. . The parachute according to any one of claims 1 to 3, wherein the umbrella body is formed by connecting a plurality of substantially triangular gores, and the pocket is formed by two gore pockets provided over two gores. The parachute according to any one of claims 1 to 3, 5, and 6, wherein the umbrella body is formed by connecting a plurality of substantially triangular gores, and the pocket is formed with one gore. Umbrella cloth with low air permeability at the umbrella edge, umbrella cloth with high air permeability at the umbrella central part, and umbrella cloth with air permeability between the umbrella edge part and the umbrella central part at the umbrella top part The parachute according to any one of claims 1 to 7, characterized in that: The parachute according to claim 8, wherein an area ratio of the umbrella edge portion: umbrella central portion: umbrella top portion is 50 to 70%: 10 to 40%: 10 to 30%. The parachute according to claim 8 or 9, wherein when the air permeability of the top of the umbrella is 1, the central part of the umbrella is 1.4 to 1.6 and the edge of the umbrella is 0 to 0.2.

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