JP2007090982A - Parachute - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a parachute with a high resistance coefficient and good stability, and capable of minimizing a weight increase. <P>SOLUTION: The parachute includes a canopy 1 which becomes almost hemispheric upon inflation. The canopy is equipped with a canopy skirt part 12 constituting a hemispheric open surface, a canopy top part 11 forming a top part of the canopy, and a canopy central part 13 connecting the canopy skirt part and the canopy top part. The parachute is characterized by providing a plurality of lobes 15 expanded by internal air of the canopy. <P>COPYRIGHT: (C)2007,JPO&INPIT

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 flat, substantially hemispherical umbrella 1 has a large resistance coefficient, the parachute area required for lowering the fallen object at a certain speed or less is small, and the parachute is dropped from the flying object or the flying object. Widely used to drop falling objects.

  As shown in FIG. 4, such a parachute includes an umbrella top 11 that forms the top of a substantially hemispherical umbrella 1, an umbrella edge 12 that forms an open surface with a maximum diameter D, and the umbrella top 11 and the umbrella edge. 12 comprises an umbrella central portion 13 to which 12 are connected. Further, some types of parachutes have an umbrella extension 14 that extends from the umbrella edge 12 and curves inward. And the descent person who carries out the deceleration fall or the suspension rope 3 which supports the suspended object 2 has the structure connected with the said umbrella edge part 12 or the said umbrella extension part 14. As shown in FIG.

  When the parachute is extended and lowered, a flow separation occurs in the vicinity of the umbrella edge 12 of the umbrella 1, thereby generating an irregular flow (wake) with a vortex (see FIG. 4). If this flow separation is close to the edge of the umbrella, an unstable region of large pressure is formed at the rear of the umbrella, the unstable pressure is exerted on the umbrella 1, and swinging occurs while the parachute is lowered, so that the stable There is a drawback that it is difficult to descend. The umbrella extension portion 14 as described above is a portion extending from the hemispherical umbrella body 1 to the lower hemisphere portion, and is formed to suppress the parachute swinging as described above and contribute to the stable descent of the parachute. It has been done.

  However, the umbrella extension part 14 has a drawback that it can be extended from the umbrella top part 11 by about 10% or less with respect to the circumferential length (surface distance) L of the umbrella edge part 12. This is because, if the umbrella extension 14 is made longer, the stability is improved, but the opening property is impaired and the weight is remarkably increased. Therefore, there is a disadvantage that the oscillating body 1 can only be controlled to have a sway of about ± 15 degrees and the weight increases.

  In order to eliminate the above drawbacks, as shown in FIG. 5, a slit 4 is provided in the umbrella rim 12 or the umbrella extension 14 of the hemispherical umbrella 1, and air is injected outward to reduce the pressure resistance. (Refer to the arrow in FIG. 5 (b)), the swing is suppressed and the posture is stabilized (Japanese Patent No. 2743171).

  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 4, it is considered that the resistance coefficient becomes small and the stability of the parachute is improved. However, in practice, this parachute is effective for the quick opening of the umbrella 1, but it has been found that it does not contribute much to the stability.
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 that has a large resistance coefficient, good stability, and can suppress an increase in weight to a minimum.

  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 and an umbrella central part that connects the umbrella edge and the umbrella top, and a plurality of lobes that are expanded by air from inside the umbrella body are provided in a circumferential direction of the umbrella edge. It is characterized by that.

  According to the present invention, a plurality of lobes that are expanded by the air from the inside of the umbrella body are provided in the circumferential direction of the umbrella edge, and since the lobes are expanded, the air flow flows along the lobes. The flow is separated at the top side, and the unstable pressure region is reduced. For this reason, the swing of the parachute is suppressed, and it is possible to descend stably. Moreover, the resistance coefficient is not lowered to improve the stability, but rather the lobe is improved, and the characteristics as a parachute are remarkably improved.

  In a preferred embodiment of the present invention, a discharge hole for discharging the air in the lobe is provided in the upper portion of the lobe. In another preferred embodiment of the present invention, the surface distance l of the lobe is 0.2 L when the surface distance of the umbrella body from the top of the umbrella to the end of the umbrella edge is L. The distance d between the most expanded portion of the lobe and the umbrella body is d = 0.02D to 0.1D with respect to the diameter D of the umbrella edge portion.

  In a preferred form according to the present invention, the umbrella body is formed by connecting a plurality of substantially triangular gores, and a lobe portion L adjacent to five gores provided with lobes is provided 45 degrees apart. And the lobe portion L is connected to a gore not having two lobes.

  In the other embodiment, the umbrella body is formed by connecting a plurality of substantially triangular gores, and the lobes are provided for every one gore or every two gores.

  In still another embodiment, the umbrella body is formed by connecting a plurality of substantially triangular gores, and one gore having a lobe and two gores having a lobe are alternately formed. It is characterized by a structure.

  In a preferred embodiment according to the present invention, a vent is formed in a portion where the lobe is not formed.

  According to the most preferred embodiment of the present invention, the umbrella edge and lobe have a small air permeability, the umbrella center has a large air permeability, the umbrella top has the umbrella edge and the umbrella center. An umbrella cloth having an air permeability in the middle of the part is used, and in this embodiment, the area ratio of the umbrella edge part: umbrella central part: umbrella top part is 50 to 70%: 10 to 40%: 10 30%. Moreover, in such a form, when the air permeability of the said umbrella top part is set to 1, the umbrella center part is 1.4-1.6, and an umbrella edge part is 0-0.2, It is characterized by the above-mentioned.

  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 has a plurality of substantially triangular gores 1a, 1b is sewn and connected, and has a structure in which a suspension cord 3 is connected to an umbrella body 1 formed in a substantially flat hemispherical shape and an umbrella edge portion 12 of the umbrella body 1 or the umbrella extension portion 14 described above (this In the embodiment, the umbrella edge 12).

  The umbrella body 1 includes an umbrella top portion 11 that forms a substantially flat hemispherical top portion, an umbrella edge portion 12 that forms an opening surface A, and an umbrella central portion 13 that connects the umbrella edge portion 12 and the umbrella top portion 11. In addition, a plurality of lobes 15 are provided in the circumferential direction of the umbrella 1 at the position of the umbrella edge 12. As shown in FIG. 3A, the lobe 15 includes an intake hole 151 that communicates with the inside of the umbrella body 1, and further includes a discharge hole 152 that discharges air above the lobe 15. For this reason, part of the air received by the umbrella 1 while the parachute is descending enters the lobe 15 through the intake hole 151, expands the lobe 15, and then is discharged from the discharge hole 152. . By forming the discharge hole 152 in this way, the air flow becomes smooth and the stability of the parachute can be improved.

  As shown in FIG. 1 and FIG. 2, in this embodiment, five adjacent gores 1a provided with lobes 15 are provided 90 degrees apart from each other, and two lobe portions L are provided. The gore 1b not provided with the lobe is connected. That is, each lobe portion L is provided at an axially symmetric position with the apex of the umbrella top portion 12 as an axis. In this embodiment, the air holes 16 are also formed in the gore 1b not provided with the lobe 15 (see FIG. 3B). By providing such a vent hole 16, the resistance coefficient of the parachute is reduced, and the stability of the parachute is increased.

  The position of the lobe 15 is not basically limited in the present invention, and it is obvious that the lobe 15 may be provided at a symmetrical position with the vertex as the axis center. For example, the lobes 15 may be provided for all the gores, or may be provided for every 1 gore or every 2 gores. Moreover, you may provide over several gores (for example, over 2 gores), for example, you may have the structure where the lobe 15 was alternately formed over what provided the lobe 15 in 1 gore, and 2 gores.

  The circumferential length l of the lobe 15 is the circumferential length of the umbrella body 1 up to the top of the umbrella top 11 and the end of the umbrella edge 12 (maximum diameter portion D; corresponding to the opening surface A in this embodiment). When L is the surface distance, it is preferably 0.2L to 0.4L. If it deviates from the range of l = 0.2L-0.4L, the effect which moves an umbrella away from a wake area | region becomes small, and there exists a possibility that favorable stability may not be acquired. The distance d between the most expanded portion of the lobe 15 and the umbrella body 1 is preferably d = 0.02D to 0.1D with respect to the diameter D of the umbrella edge. If it is smaller than d = 0.02D, the effect of rectifying the air flow is small. On the other hand, if it is larger than d = 0.1D, a vortex is generated in the vicinity of the umbrella edge and the stability is lowered.

  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, the cloth P1 that normally transmits air to the umbrella top part 11, the cloth P2 that easily transmits air to the umbrella central part 13, and the cloth P3 that hardly transmits air to the umbrella edge part 12 and the lobe 15 are used. As for the air permeability, when the air permeability (umbrella top) of a normal parachute is 1, the umbrella central part is 1.4 to 1.6, and the umbrella edge and lobe 15 are 0 to 0.2. Is preferred.

  By using a cloth that does not easily transmit air to the umbrella edge 12 and the lobe 15, the pressure inside the umbrella body 1 is increased, and the internal pressure of the umbrella body 1 is increased, thereby increasing the projected area and drag. Can be improved. In addition, the use of the above-described fabric for the umbrella edge 12 improves the flow of air and opens the umbrella quickly, so that stability is also improved.

  By using the cloth P1 that allows air to permeate as usual at the umbrella top 11, 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 the cloth P2 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 effects may not be exhibited if it deviates from these ranges.

  According to the present invention, a plurality of lobes that are expanded by the air from the inside of the umbrella body are provided in the circumferential direction of the umbrella edge, and since the lobes are expanded, the air flow flows along the lobes. The flow is separated at the top side, and the unstable pressure region is reduced. For this reason, the swing of the parachute is suppressed, and it is possible to descend stably. Moreover, the resistance coefficient is not lowered to improve the stability, but rather the lobe is improved, and the characteristics as a parachute are remarkably improved.

The side view of one Example of this invention. The top view of one Example of this invention. The figure explaining the effect | action of the said Example. The side view of the conventional parachute. The side view of the other type | formula parachute of the past.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Umbrella body 11 Umbrella top part 12 Umbrella edge part 13 Umbrella center part 14 Umbrella extension part 15 Lobe 151 Intake hole 152 Discharge hole 2 Dropper (suspended object)
3 Suspension rope 4 Slit 16 Vent

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 lobes are provided in a circumferential direction of the umbrella edge part to expand by air from inside the umbrella body. The parachute according to claim 1, wherein a discharge hole for discharging air in the lobe is provided in an upper portion of the lobe. The surface distance l of the lobe is 0.2L to 0.4L, where L is the surface distance of the umbrella body from the top of the umbrella to the end of the umbrella edge, and is the most expanded of the lobe. The parachute according to claim 1, wherein a distance d between the portion and the umbrella body is d = 0.02D to 0.1D with respect to a diameter D of the umbrella edge portion. The umbrella body is formed by connecting a plurality of substantially triangular gores, and a lobe portion L adjacent to five lobes provided with lobes is provided 45 degrees apart. The parachute according to any one of claims 1 to 3, wherein a gore not having two lobes is connected. 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 lobes are provided for every one gore or every two gores. The umbrella body is formed by connecting a plurality of substantially triangular gores, and has a structure in which one gore has a lobe and two gores have a lobe alternately formed. The parachute according to any one of claims 1 to 3. The parachute according to any one of claims 1 to 6, wherein a vent hole is formed in a portion where the lobe is not formed. Umbrella cloth having a small air permeability at the umbrella edge and lobe, an umbrella cloth having a large air permeability at the umbrella central part, and an umbrella cloth having an air permeability intermediate between the umbrella edge part and the umbrella central part at the umbrella top part. The parachute according to claim 1, wherein the parachute is used. 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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