JP2015229390A - Landing gear of aircraft - Google Patents

Abstract

PROBLEM TO BE SOLVED: To further reduce air noises of landing gear.SOLUTION: Landing gear 1 includes a stud 2 for supporting a wheel 51, and link members (an upper arm 31, a lower arm 32, an upper link 41, and a lower link 42) which are attached to the stud. The link member has connection parts 311 and 411 on the side of one end, connection parts 312 and 412 on the side of the other end, and intermediate parts 313, 314 and 413 that connect the connection parts on the side of the one end and the connection parts on the side of the other end to one another. A clearance between both side edges of the intermediate part is closed.

Description

  The technology disclosed herein relates to an aircraft landing gear.

  For example, in Patent Document 1, in order to prevent air noise in the landing gear, there are a pedestal and a rod-like portion that connects the pedestal and the trunnion by being attached obliquely to the pedestal. It is described that a plate-like portion that prevents inflow and outflow of airflow is provided between them.

Japanese Patent No. 5416988

  As described above, although measures for preventing air noise are known between the pedestal and the rod-shaped portion in the landing gear, it is required to further reduce the air noise in the landing gear. .

  The technology disclosed herein has been made in view of such a point, and an object thereof is to further reduce air noise in the landing gear.

  The technology disclosed herein employs a configuration that reduces air noise for a link member that is attached to a pedestal, specifically, a link member that constitutes a link mechanism such as a torque link or a brace. In particular, the technology disclosed herein shows that the flow of air flowing around the landing gear is disturbed without attaching a separate rectifying member such as a fairing independent of the main parts constituting the landing gear to the landing gear. By suppressing or preventing, air noise in an aircraft landing gear is reduced. For this reason, the technology disclosed herein prevents an air flow flowing through the link member. This prevents an air flow turbulence field from being formed immediately behind the link member.

  Specifically, an aircraft landing gear disclosed herein includes a pedestal configured to support a wheel, and a link member attached to the pedestal, and the link member includes a coupling portion on one end side. And an intermediate portion that connects the one end side connecting portion and the other end side connecting portion to each other, and the intermediate portion has a gap between both side edges. It is configured to be closed.

  Here, the “link member” is a member that constitutes a link mechanism, and is arranged so as to bridge between two predetermined members, and the coupling portion on one end side is the other end with respect to one member. The coupling portion on the side is coupled to the other member, and at least one of the coupling portion on one end side of the link member and the coupling portion on the other end side is pivotally coupled to the member, It can be defined as a structural member that can operate. In this respect, the link member in the present configuration is different from a rod-like portion as a reinforcing member that joins the pedestal and the trunnion as described in Patent Document 1. Specifically, the link member may be a structural member that moves when the landing gear of the aircraft is deployed and retracted, or a structural member that moves in response to the buffering operation of the pedestal. As a more specific example, an upper arm and a lower arm constituting a torque link, and an upper link and a lower link constituting a side brace and a drag brace can be used as examples of the link member. However, the link member is not limited to these members.

  According to the above configuration, in the link member, the intermediate portion that connects the coupling portion on one end side and the coupling portion on the other end side is closed. When the intermediate portion is not closed, for example, when there is a through-hole that penetrates the intermediate portion, air passes through the through-hole, thereby forming a shear turbulent flow immediately behind the link member. Pressure fluctuations on the surface of the link member and its peripheral parts due to this disturbance cause noise.

  On the other hand, in the said structure, the intermediate part of a link member is obstruct | occluded. For this reason, an air flow does not pass through this intermediate part. It may be said that an air flow does not pass between both side edges of the intermediate part that the part between both side edges of the intermediate part is closed. The flow of air flowing around the link member bypasses the intermediate part of the link member and flows outside the side edges at the intermediate part. Therefore, a turbulent field is not formed immediately behind the link member, and air noise caused by the turbulent field is suppressed or prevented.

  The link members are first and second arm members that are arranged on the front side or the rear side of the pedestal and are pivotally coupled to each other to form a torque link. Each of the intermediate portions includes a pair of flanges that connect the connecting portion on the one end side and the connecting portion on the other end side, and a web that is disposed between the pair of flanges and closes between the pair of flanges, It is good also as comprising.

  In the conventional configuration, the torque link including the first and second arm members is not provided with a web between the pair of flanges in the first and second arm members, or provided with a web. In addition, a through-hole (that is, a hollow hole) was formed mainly for weight reduction. The torque link is arranged on the front side or the rear side of the pedestal. However, in the configuration in which the torque link is arranged on the front side of the pedestal, a through-hole or the like exists in the intermediate portion between the first and second arm members. As a result, air flows into the space between the torque link and the pedestal through the through hole. The shear turbulence formed through the through-hole goes downstream while entraining surrounding air and collides with the pedestal. Thus, a complex turbulent field is formed around the pedestal. This turbulence field is itself a noise source, but it also causes pressure fluctuations on the pedestal and surrounding parts. The shear turbulence formed through the through holes in this way also contributed to the generation of noise from peripheral parts. Further, in the configuration in which the torque link is arranged on the rear side of the pedestal, air can flow through the through hole in the middle part of the first and second arm members. As air flows into the space between the column and the torque link, the air flow is disturbed, and as it passes through the through hole, the air flow behind the torque link is also disturbed. It was increasing.

  On the other hand, in the said structure, between a pair of flanges in the 1st and 2nd arm member which comprises a torque link is obstruct | occluded with the web, and the through-hole etc. do not exist in the web. For this reason, in the configuration in which the torque link is arranged on the front side of the pedestal, air does not flow into the space between the torque link and the pedestal through the first and second arm members, and the torque link The static pressure in the space between the pedestals is relatively increased. As a result, the air flow that flows around the torque link located on the front side of the pedestal flows as it is to the side of the pedestal, and the disturbance of the air flow is suppressed or prevented. As a result, air noise is suppressed or prevented. The torque link arranged on the front side of the footnote can perform the same function as the fairing.

  Further, in the configuration in which the torque link is disposed on the rear side of the pedestal, the static pressure in the space between the pedestal and the torque link is relatively high because the first and second arm members are closed. Become. As a result, the air flowing around the pedestal is prevented or prevented from flowing into the space between the pedestal and the torque link, and flows through the side of the torque link as it is. In this way, air noise is suppressed or prevented by suppressing or preventing disturbance of the air flow.

  In either case where the torque link is arranged on the front side of the pedestal or on the rear side of the pedestal, air noise in the landing gear can be reduced without separately arranging a rectifying member such as a fairing. .

  Moreover, the web which close | closes between a pair of flanges in the intermediate part of a 1st and 2nd arm member raises the rigidity of the 1st and 2nd arm member whole, As a result, the 1st and 2nd arm member of It may be possible to reduce weight. That is, the web may contribute not only to the above-described air noise reduction effect and also to the rigidity improvement effect of the first and second arm members as well as the air noise reduction effect.

  The landing gear of the aircraft further includes a supply path for supplying hydraulic pressure to a brake device provided on the wheel, and at least a part of the supply path is provided in the torque link. Good.

  In the conventional configuration, a hydraulic pipe for supplying hydraulic pressure to the wheel brake device attached to the lower end of the pedestal is disposed along the outside of the torque link, and an appropriate portion of the pipe is clamped or the like. It was fixed to the torque link via. Such hydraulic pipes and clamps are equivalent to providing unevenness on the surface of the torque link, and this unevenness disturbs the flow of air flowing around the torque link and increases air noise.

  On the other hand, in the said structure, at least one part of the supply path of the hydraulic pressure with respect to a brake device is provided in the inside of a torque link. This makes it possible to reduce or eliminate hydraulic piping and clamps exposed to the outside. Since the unevenness of the surface of the torque link is reduced or eliminated, the air flow flowing around the torque link is prevented or prevented from being disturbed, which is advantageous for suppressing or preventing air noise. This configuration can prevent air noise without a fairing that covers the hydraulic piping and clamps.

  Thus, the hydraulic pipes and clamps exposed to the outside around the torque link are reduced or eliminated, and the intermediate portion of the first and second arm members constituting the torque link is closed by the web. In combination, the effect of suppressing or preventing air noise in the landing gear is further enhanced.

  A linear member may be disposed inside the torque link. Here, the linear member can be a signal line that transmits various electrical signals. The linear member can be a power line for supplying driving power to an actuator or the like. Furthermore, the linear member can be a cable that mechanically connects predetermined devices. The configuration and application of the linear member are not limited to a specific configuration and application.

  In the conventional configuration, a linear member such as a signal line is also arranged along the outside of the torque link, as in the above-described hydraulic piping, and an appropriate place in the middle is interposed via a clamp or the like. It was fixed to the torque link. Accordingly, the linear member also increases the air noise by increasing the unevenness of the surface of the torque link and disturbing the air flow, like the hydraulic piping.

  On the other hand, in the said structure, a linear member is arrange | positioned inside a torque link. This reduces or eliminates linear members and clamps exposed to the outside around the torque link. Therefore, it becomes possible to suppress or prevent the turbulence of the air flow generated due to the linear member or the like. As a result, it is advantageous for suppressing or preventing air noise.

  The link member is a member that forms a brace having a base end portion coupled to the pedestal and extending from the pedestal toward the body side, and a distal end portion coupled to the body. An intermediate portion of the link member that constitutes the link member is disposed between the pair of flanges that connect the coupling portion on the one end side and the coupling portion on the other end side, and between the pair of flanges, and closes between these It is good also as being comprised including the web to do. Here, the brace may be a side brace arranged so as to extend obliquely upward from the pedestal toward the inside of the fuselage when the pedestal is lifted and lowered in a direction perpendicular to the axle. Alternatively, it may be a drag brace arranged so as to extend obliquely upward from the pedestal toward the body when the pedestal is lifted and lowered in the direction of the aircraft axis.

  Also in the link member constituting the side brace or the drag brace, the intermediate portion is closed between the pair of flanges and the pair of flanges similarly to the first and second arm members constituting the torque link described above. By including the web to be configured, the formation of a turbulent field immediately behind the link member is suppressed or prevented. As a result, also in the brace, air noise can be suppressed and prevented similarly to the torque link described above.

  Unlike this configuration, the intermediate portion of the link member constituting the brace may have a cross-sectional shape of a circle, an ellipse, a wing, or a streamline shape.

  In the conventional configuration, the link member constituting the side brace or the drag brace has, for example, a H-shaped or I-shaped cross section by a pair of flanges and a web between the flanges, and has a large surface unevenness. The turbulence of the air flow flowing around the link member was strong. As a result, in the conventional configuration, air noise was likely to increase, but in the configuration described above, the cross-sectional shape of the intermediate portion of the link member constituting the brace is a circle, an ellipse, a wing, or a streamline shape. Like that. With this configuration, the unevenness of the surface is substantially eliminated, so that the turbulence of the air flow that flows around the link member constituting the brace is suppressed or prevented. As a result, air noise can be suppressed or prevented. Since this structure does not provide a through-hole or the like in the intermediate portion of the link member, an effect of suppressing air noise by preventing the air flow passing through the intermediate portion can also be obtained.

  The landing gear of the aircraft includes a hydraulic actuator that is attached to the brace, and that releases a lock of a leg-lowered state of the pedestal by the brace, and a supply / discharge passage that supplies and discharges hydraulic pressure to the hydraulic actuator. Furthermore, it is good also as at least one part of the said supply / discharge path being provided in the inside of the link member which comprises the said brace.

  In the conventional configuration, a pipe for supplying and discharging hydraulic pressure to a so-called down lock release actuator is arranged along the brace and fixed with a clamp. In this configuration, at least a part of the supply and discharge path is By providing it inside the link member that constitutes the brace, unevenness on the surface of the brace is reduced or eliminated. Therefore, air flow disturbance caused by such piping is suppressed or prevented, and air noise is suppressed or prevented. Is possible.

  A linear member may be disposed inside the link member constituting the brace.

  By doing so, similarly to the torque link described above, in the side brace and drag brace, it is possible to suppress or prevent the turbulence of the air flow caused by the linear members arranged along the brace. This is advantageous for suppressing or preventing air noise.

  As described above, according to the aircraft landing gear described above, since the intermediate part of the link member attached to the pedestal is configured by closing the space between both side edges thereof, immediately behind the link member. A turbulent field of air is not formed, and air noise caused by this turbulent field can be suppressed or prevented.

1 is a perspective view illustrating an aircraft landing gear. It is a side view of an landing gear. It is sectional drawing of a torque link. It is IV-IV sectional drawing of FIG. It is a perspective view of the pivot shaft of a torque link. It is a figure corresponding to FIG. 1 which illustrates the landing gear of a conventional structure. FIG. 5 is a view corresponding to FIG. 4 illustrating a cross section of a torque link of a landing gear having a conventional configuration. (A) It is a figure which shows the shape of the torque link of the conventional structure as an analysis object, (b) The torque link which concerns on the structure of this embodiment as an analysis object. (A) It is a figure which shows the analysis result of the air flow around the torque link of a conventional structure, (b) The analysis result of the air flow around the torque link which concerns on the structure of this embodiment.

  Hereinafter, embodiments of the technology disclosed herein will be described with reference to the drawings. The following description is an example. 1 is a perspective view of the landing gear 1, and FIG. 2 is a side view of the landing gear 1. The left front side of the paper in FIG. 1, the left side of the paper in FIG. 2 is the front side of the aircraft, and the right rear side of the paper in FIG. 2, the right side of the drawing in FIG. 2 corresponds to the rear side of the aircraft, and the landing gear 1 shown in FIGS. 1 and 2 is the main landing gear on the starboard of the aircraft. However, the technique disclosed here can also be applied to the front legs. In the following, for convenience of explanation, the direction connecting the left front side of the paper and the right back side of the paper in FIG. 1 (that is, the direction corresponding to the front-rear direction of the aircraft) is referred to as the X direction. The direction connecting the left back (that is, the direction corresponding to the left and right direction of the aircraft) is called the Y direction, and the direction connecting the top and bottom of the page in FIG. 1 (that is, the direction corresponding to the vertical direction of the aircraft) is called the Z direction. .

  The landing gear 1 for an aircraft includes at least a pedestal 2 that supports a wheel 51, and a torque link 3 and a side brace 4 that are configured by link members attached to the pedestal 2.

  The pedestal 2 is a buffer post and includes a strut cylinder 21 and a strut piston 22. The strut cylinder 21 is disposed on the upper side, and the strut piston 22 is disposed on the lower side. The strut piston 22 is disposed so as to be coaxial with the strut cylinder 21 and is inserted into a lower end opening of the strut cylinder 21. The strut piston 22 reciprocates relative to the strut cylinder 21 in the Z direction.

  A trunnion 23 is provided at the upper end of the strut cylinder 21 so as to be pivotable about the deployment axis of the landing gear 1 with respect to the aircraft body (not shown).

  Although only one is shown in the lower end of the strut piston 22 in FIGS. 1 and 2, a pair of wheels 51 are disposed on both sides in the Y direction across the strut piston 22. At the lower end of the strut piston 22, brake devices 52 are disposed on both sides in the Y direction across the strut piston 22 so as to correspond to the pair of wheels 51. As will be described later, the brake device 52 operates by receiving supply of hydraulic pressure.

  The torque link 3 prevents the strut piston 22 inserted into the strut cylinder 21 from rotating about the axis while allowing the strut piston 22 to move (extend or contract) relative to the strut cylinder 21 in the Z direction. . In the illustrated example, the torque link 3 is disposed between the pair of wheels 51 and 51 on the front side of the pedestal 2. The torque link 3 has an upper arm 31 and a lower arm 32. The upper arm 31 and the lower arm 32 correspond to the first and second arm members. In the state where the landing gear 1 is deployed as shown in FIG. 2, the upper arm 31 and the lower arm 32 of the torque link 3 form a “<” shape in a side view.

  As shown in FIGS. 1 and 3, the upper arm 31 includes a pair of attachment portions 311 that are pivotally attached to the strut cylinder 21 via a first attachment shaft 33 (that is, corresponding to a coupling portion on one end side), A pair of flanges 312 that are pivotally connected to the lower arm 32 via a pivot shaft 34 (that is, corresponding to the coupling portion at the other end), and a pair of flanges that connect the mounting portions 311 and the pivot portion 312 to each other. 313 and a web 314 disposed between the pair of flanges 313. The pair of attachment portions 311 are arranged at a predetermined interval in the Y direction. Each attachment portion 311 is formed with a hole 311a through which the first attachment shaft 33 is inserted. Further, a hole 312a into which the pivot shaft 34 is inserted is formed in the pivot portion 312 so as to penetrate therethrough. The pair of flanges 313 are arranged so as to extend from the pivotal support portion 312 toward each of the pair of attachment portions 311 arranged at a predetermined interval in the Y direction. Thereby, the upper arm 31 as a whole has a substantially triangular shape or a substantially trapezoidal shape.

  Similarly to the upper arm 31, the lower arm 32 has a pair of mounting portions 321 (that corresponds to a coupling portion on one end side) that are pivotally mounted to the strut piston 22 via the second mounting shaft 35, and an upper arm. A pair of flanges that connect the pivots 322 (that corresponds to the coupling portion on the other end side) pivotally connected to the bearing 31 via the pivot shaft 34, and the attachments 321 and the pivots 322. 323 and a web 324 disposed between the pair of flanges 323. The pair of attachment portions 321 are arranged at a predetermined interval in the Y direction, and each attachment portion 321 is formed with a hole 321a through which the second attachment shaft 35 is inserted. The pivot 322 is formed with a hole 322a through which the pivot shaft 34 is inserted. The pair of flanges 323 are arranged so as to extend from the pivotal support part 322 toward each of the pair of attachment parts 321 arranged at a predetermined interval in the Y direction. It has a shape. In addition, the shape of the upper arm 31 and the lower arm 32 shown in the figure is an example, and is not limited to the shape shown here. The shapes of the upper arm 31 and the lower arm 32 can be set to appropriate shapes. Further, the shape of the upper arm 31 and the shape of the lower arm 32 are not necessarily the same, and may be different from each other. Details of the characteristic configuration of the torque link 3 will be described later.

  The side brace 4 supports the pedestal 2 when the landing gear 1 is deployed. In the illustrated example, the side brace 4 is disposed so as to extend obliquely upward from the inner side of the pedestal 2 toward the inside of the body. The side brace 4 includes an upper link 41, a lower link 42, and a lock link 43. One end portion of the upper link 41 constitutes a coupling portion 411 on one end side that is pivotally fixed to an aircraft body (not shown). The other end portion of the upper link 41 constitutes a coupling portion 412 on the other end side that is pivotally connected to the lower link 42. One end portion of the lower link 42 constitutes a coupling portion 421 on one end side that is pivotally connected to the other end portion of the upper link 41. The other end portion of the lower link 42 constitutes a coupling portion 422 on the other end side that is pivotally attached to the attachment portion 24 provided in the intermediate portion of the strut cylinder 21.

  The lock link 43 includes a pair of first and second link members 431 and 432 that are pivotally coupled to each other. The first link member 431 is connected to the pivotal coupling portion between the upper link 41 and the lower link 42. It is connected so that it can rotate. The second link member 432 is attached to the second attachment portion 25 provided at the upper end portion of the strut cylinder 21. The lock link 43 is a link that locks the landing gear 1 in the expanded state by fixing the side brace 4 in the expanded state, and the lock link 43 is locked between the lower link 42 and the lock link 43. A down-lock release actuator 44 is provided that enables the side brace 4 to be folded and thus retracted by the landing gear 1. As will be described later, the down lock release actuator 44 is driven by hydraulic pressure. Details of the characteristic configuration of the side brace 4 will also be described later.

  In this landing gear 1, various configurations are employed that suppress or prevent air noise by suppressing or preventing air flow disturbance. Each configuration described below is particularly characterized in that a rectifying member such as a fairing is not required. Hereinafter, those configurations will be described in detail in order.

(Blocking configuration to prevent air flow through the torque link)
As shown in FIGS. 3 and 4, the torque link 3 includes webs 314 and 324 that close between the pair of flanges 313 and 323 in each of the upper arm 31 and the lower arm 32. The webs 314 and 324 contribute to the reduction of air noise, as will be described later. That is, as is apparent from FIG. 3, the webs 314 and 324 are not formed with through holes such as a hollow hole, and completely close between the pair of flanges 313 and 323. Air flow is prevented from passing between the flanges 313 and 323. The torque link 3 of the landing gear 1 of this configuration includes a pair of intermediate arms that connect the coupling portions 311 and 321 on one end side and the coupling portions 312 and 322 on the other end side in each of the upper arm 31 and the lower arm 32. It can be said that the gaps between the side edges of the intermediate part constituted by the edges of the flanges 313 and 323 are closed by the flanges 313 and 323 and the webs 314 and 324.

  Although details will be described later, this configuration suppresses or prevents the formation of shear turbulence immediately behind the torque link 3. As a result, aerodynamic noise caused by this disturbance is suppressed or prevented.

  In contrast to this configuration, in the conventional landing gear 10 shown in FIGS. 6 and 7, the upper arm 310 and the lower arm 320 constituting the torque link 30 are generally not closed between the pair of flanges 3130 and 3230. It is. In the torque link 30 shown in the figure, no web is provided between the pair of flanges 3130 and 3230. In addition, in the landing gear 10 of the conventional configuration shown in FIGS. 6 and 7, the same reference numerals are given to the same components as the landing gear 1 of the main configuration shown in FIG. 1 and the like, and 0 is added to the end of the corresponding configuration. doing.

  7, in the conventional landing gear 10, webs 3140 and 3240 are disposed between a pair of flanges 3130 and 3130 in the torque link 30, and through holes are formed in the webs 3140 and 3240. In some cases, 3150 and 3250 (that is, a lightening hole) are provided.

  In any configuration, in the torque link 30 of the conventional configuration, air passes between the pair of flanges 3130 and 3230 of the upper arm 310 and the lower arm 320. The air flow passing between the flanges 3130 and 3230 generates a turbulent field of the air flow immediately behind the torque link 30 and increases air noise.

  Next, the analysis performed regarding the effect of reducing the air noise by closing between the flanges in the torque link will be described. FIG. 8 shows the shape of the torque link to be analyzed. The shape of the torque link is slightly different from the shape of the torque link shown in FIG. 1 and the like, but the upper arm and the lower arm are respectively connected to one end side coupling portion, the other end side coupling portion, and the one end side coupling. The basic configuration having a pair of flanges that connect the portion and the coupling portion on the other end side is the same. Therefore, although the shapes are different, the same components are denoted by the same reference numerals.

  In the torque link 30 shown in FIG. 8A, through holes 3150 and 3250 are formed in webs 3140 and 3240 arranged between a pair of flanges 3130 and 3230 in each of the upper arm 310 and the lower arm 320. On the other hand, in the torque link 3 shown in FIG. 8B, in each of the upper arm 31 and the lower arm 32, through holes are not formed in the webs 314 and 324 disposed between the pair of flanges 313 and 323, The webs 314 and 324 completely block between the pair of flanges 313 and 323. Here, in order to simulate the landing of an aircraft, the flow around the torque link when each of these two torque links 3 and 30 are placed in a uniform flow in the positive direction of the X axis is described as LES (Large Eddy Simulation).

  The fluid analysis solver STAR-CCM + (V8.04.007) from CD-adapco was used for the calculation. STAR-CCM + analyzes the Navier-Stokes equation system using the cell-centered finite volume method with second-order accuracy. The calculation area is set sufficiently wide so as not to affect the flow field around the torque link. The fluid was assumed to be incompressible viscous air. The boundary condition was an adhesion condition on the torque link surface. The distant inlet has a uniform flow velocity, and the flow velocity is 68 m / s as the aircraft speed at the time of landing. The outlet was set at a reference static pressure (103235 Pa), and the side of the calculation area was traction free.

  FIG. 9 shows the analysis result. This figure is an isosurface of the Y-direction vorticity at a certain moment. The dark and light area is a vortex in the −Y direction, and the light and light area is a vortex area in the + Y direction. FIG. 9A shows a flow around the torque link 30 in which the through holes 3150 and 3250 are provided in the webs 3140 and 3240 shown in FIG. 8A. According to this, when the through holes 3150 and 3250 are provided in the webs 3140 and 3240, the through holes 3150 and 3250 are arranged so as to be opposed to the air flow in the positive direction of the X axis. It passes through the through hole. The airflow that has passed through the through hole forms a shear layer with the low speed region behind the torque link. This shear layer entrains the surrounding air, so that a turbulent flow is formed and maintained immediately after the torque link 30. This shear turbulence causes a pressure fluctuation on the back surface of the torque link and becomes a noise source.

  On the other hand, FIG. 9B shows a flow around the torque link 3 in which the through holes are not provided in the webs 314 and 324 shown in FIG. 8B. According to this, when the through holes are not provided in the webs 314 and 324, the gap between the pair of flanges 313 and 323 is completely closed, so that it can be seen in FIG. Such shear turbulence is not formed. Although a turbulence field is formed at a position slightly away from the torque link 3 by the air flow flowing to the side of the torque link 3, the turbulence is small compared to (a). As a result, it can be seen that the torque link 3 with the flanges closed has an effect of suppressing noise emission.

  In this way, in the upper arm 31 and the lower arm 32 constituting the torque link 3, an air flow turbulence field is formed immediately behind the torque link 3 by preventing an air flow that passes through the intermediate portion of the arm. Is suppressed or prevented, and air noise can be suppressed or prevented.

  The torque link 3 is also disposed between the pair of wheels 51 and 51 on the front side of the pedestal 2 in the illustrated example. In this arrangement, to prevent the air flow passing through the torque link 3, the air flow that bypasses the torque link 3 on the front side of the pedestal 2 flows in the space between the torque link 3 and the pedestal 2. Suppresses inflow. As a result, the air flow passes between the pillar 2 and the wheel 51 and reaches the rear of the landing gear 1. This also has an advantage in suppressing or preventing air noise by suppressing or preventing air flow disturbance.

  Unlike the illustrated example, the torque link 3 may be disposed on the rear side of the pedestal 2. In the arrangement configuration, preventing air flow through the torque link 3 relatively increases the static pressure in the space between the pedestal 2 and the torque link 3, and air flows around the pedestal 2. Is suppressed from flowing into the space between the pedestal 2 and the torque link 3, and the air flow passes between the torque link 3 and the wheels 51 and reaches the rear of the landing gear 1. . Even in this configuration, the disturbance of the air flow is suppressed or prevented, which is advantageous for suppressing or preventing air noise.

  In the upper arm 31 and the lower arm 32, the webs 314 and 324 that close the gap between the pair of flanges 313 and 323 function as a rigid member that connects the pair of flanges 313 and 323 to each other. In particular, if the webs 314 and 324 are not provided with through holes, stress concentration is avoided and the rigidity of the upper arm 31 and the lower arm 32 is improved. This is advantageous in reducing the weight of the upper arm 31 and the lower arm 32 while ensuring the necessary strength.

  In addition, as a structure which prevents the air flow which passes the torque link 3, it is not limited to the structure mentioned above, especially the shape of the torque link 3 mentioned above. In other words, in the above-described configuration, the cross-sections of the upper arm 31 and the lower arm 32 are substantially H-shaped by the pair of flanges 313 and 323 and the relatively thin webs 314 and 324 that close between the flanges 313 and 323. The upper arm 31 and the lower arm 32 are each provided with a dent (see, for example, FIG. 4) so as to form an I shape or an I shape. However, the shapes of the upper arm 31 and the lower arm 32 are not limited to this shape. For example, the surfaces of the upper arm 31 and the lower arm 32 may be flattened by increasing the thickness of the webs 314 and 324. Further, in the above-described configuration, the webs 314 and 324 are arranged in the center with respect to the thickness direction of the flanges 313 and 323, so that recesses having the same depth are provided on the front and back surfaces of the upper arm 31 and the lower arm 32, respectively. However, by changing the arrangement of the webs 314 and 324 with respect to the thickness direction of the flanges 313 and 323, the depth of the recesses on the surface of the upper arm 31 and the lower arm 32 and the depth of the recesses on the back surface can be made different. Good. Alternatively, the upper arm 31 and the lower arm 32 may be flattened and a recess may be provided only on the back surface, or conversely, the upper arm 31 and the lower arm 32 may be flattened and a recess may be provided only on the front surface. You may do it.

  Furthermore, each of the upper arm 31 and the lower arm 32 of the torque link 3 may be formed in a hollow shape, and various shapes such as a rectangular shape can be adopted as the cross-sectional shape in that case.

(Configuration to reduce or eliminate unevenness of torque link surface by incorporating hydraulic piping)
As shown in FIG. 3, a hydraulic pressure supply path that supplies the brake device 52 is provided inside the torque link 3. As shown in FIG. 4, the supply paths 315 and 325 provided in the upper arm 31 and the lower arm 32 are provided in a pair of relatively thick flanges 313, respectively. 3 indicates a gradually changing portion where the wall thickness gradually changes between the flange 313 and the web 314. Here, the gradually changing portion is regarded as a part of the flange 313. .

  The supply paths 315 and 325 in the upper arm 31 and the lower arm 32 open to the inner peripheral surfaces of the holes 311a and 321a in which the first mounting shaft 33 and the second mounting shaft 35 are inserted in the pair of mounting portions 311 and 321, respectively. ing. The openings constitute supply / discharge ports 315a and 325a. Similarly to the attachment portions 311 and 321, in the pivot support portions 312 and 322, the supply paths 315 and 325 are opened on the inner peripheral surfaces of the holes 312a and 322a into which the pivot shaft 34 is inserted. The openings constitute supply / discharge ports 315b and 325b. The supply paths 315 and 325 in the upper arm 31 and the lower arm 32 are independently configured between the two attachment portions 311 and 321 and the one pivotal portion 312 and 322. Therefore, two supply / exhaust ports 315b and 325b are provided in the pivot portions 312 and 322, respectively. The layout of the supply paths 315 and 325 in the upper arm 31 and the lower arm 32 is not limited to the illustrated example.

  The upper arm 31 and the lower arm 32 in which the supply paths 315 and 325 are formed may be created by casting, for example, or may be created using so-called 3D modeling. In addition, depending on the layout of the supply path, the supply path may be formed inside the upper arm 31 and the lower arm 32 by molding, for example, by drilling.

  The hydraulic pressure supply path in the torque link 3 is also provided in a pivot shaft 34 that pivotally couples the upper arm 31 and the lower arm 32. As shown in FIGS. 3 and 5, two supply paths 341 and 341 extending in the Y direction are provided in the pivot shaft 34. The two supply paths 341 and 341 are parallel and displaced in the Y direction. The pivot shaft 34 is also formed with a communication hole 342 that extends in the radial direction from each supply passage 341 and opens on the outer peripheral surface of the pivot shaft 34. The communication hole 342 is provided at each of a position corresponding to the supply / discharge port 315b of the upper arm 31 and a position corresponding to the supply / discharge port 325b of the lower arm 32, and the pivot shaft 34 has a total of four communication holes. A hole 342 is provided. The communication hole 342 communicates with the supply / discharge ports 315b and 325b. As shown in FIG. 5, each communication hole 342 opens over a predetermined angular width on the outer peripheral surface of the pivot shaft 34. The opening angle of the communication hole 342 corresponds to the movable angle of the torque link 3.

  In addition, the code | symbol 344 shown in FIG. 5 is a groove | channel where sealing members, such as an O-ring, are arrange | positioned, for example (in the figure example, illustration of an O-ring is abbreviate | omitted). The groove 344 is annularly provided on both sides of the opening of the two communication holes 342 on the outer peripheral surface of the pivot shaft 34 in the axial direction. Thus, the space between the pivot portions 312 and 322 of the upper arm 31 and the lower arm 32 and the pivot shaft 34 is sealed.

  The hydraulic pressure supply passage in the torque link 3 is also provided in the first attachment shaft 33 for pivotally attaching the upper arm 31 to the strut cylinder 21. The two supply paths 331 and 331 provided in the first mounting shaft 33 extend along the axial center so as to open to both end surfaces. The opening of each supply path 331 is closed by a bolt 333. The first mounting shaft 33 is also formed with a communication hole 332 that extends in the radial direction from each supply passage 331 and opens on the outer peripheral surface of the first mounting shaft 33. The communication hole 332 is provided at a position corresponding to the supply / exhaust port 315a provided in each attachment portion 311 of the upper arm 31 and communicates with the supply / exhaust port 315a. Although not shown in the drawings, the communication hole 332 opens over a predetermined angular width on the outer peripheral surface of the first mounting shaft 33, similarly to the communication hole 342 of the pivot shaft 34. The first mounting shaft 33 is further provided with second communication holes 334 communicating with the supply passages 331 on the center side in the axial direction. The second communication holes 334 are respectively shown in FIGS. As shown, the hydraulic piping 521 extending from the machine body side and disposed along the pedestal 2 is connected.

  The seal structure of the first mounting shaft 33 is configured in the same manner as the seal structure of the pivot shaft 34. In the illustrated example, seals are disposed on both sides of the opening of the communication hole 332 at a position where the hole 311a of the mounting portion 311 of the upper arm 31 contacts the inner peripheral surface. Further, in the first mounting shaft 33, seals are also provided around the opening of the supply path 331 on both side end surfaces to seal between the bolts 333.

  The hydraulic pressure supply path in the torque link 3 is also provided in the second mounting shaft 35 for pivotally mounting the lower arm 32 to the strut piston 22. The two supply paths 351 provided on the second mounting shaft 35 are open on both side end surfaces of the second mounting shaft 35, similarly to the supply path 331 of the first mounting shaft 33. A bolt 353 is attached to the opening of each supply passage 351, but a through hole is formed in the bolt 353, and the supply passage 351 of the second attachment shaft 35 communicates with the outside through the through hole. doing. As shown in FIGS. 1 and 2, an external pipe 522 connected to each of the pair of brake devices 52 is connected to the through hole of the bolt 353. The second mounting shaft 35 is also formed with a communication hole 352 that extends in the radial direction from each supply passage 351 and opens on the outer peripheral surface of the second mounting shaft 35. The communication hole 352 is provided at a position corresponding to the supply / exhaust port 325a provided in each attachment portion 321 of the lower arm 32, and the communication hole 352 communicates with the supply / exhaust port 325a. Although not shown in the drawings, the communication hole 352 opens over a predetermined angular width on the outer peripheral surface of the second mounting shaft 35, similarly to the communication hole 342 of the pivot shaft 34.

  The seal structure on the second mounting shaft 35 is substantially the same as the seal structure on the first mounting shaft 33. In the illustrated example, on both side end surfaces of the second mounting shaft 35, both sides sandwiching the opening of the communication hole 352 around the opening of the supply path 351 and the position contacting the inner peripheral surface of the hole 321 a of the mounting portion 321 of the lower arm 32. Each is provided with a seal.

  In this way, the hydraulic pressure supplied from the machine body through the hydraulic pipe 521 passes through two independent supply paths provided inside the first mounting shaft 33, the upper arm 31, the pivot shaft 34, the lower arm 32, and the second mounting shaft 35. The brake device 52 is supplied.

  In addition, the structure of the supply path in an upper arm, a lower arm, a pivot shaft, and a fixed shaft is not limited to the structure shown in the figure. An appropriate configuration can be adopted so as to correspond to the shapes of the upper arm and the lower arm.

  In the landing gear 10 having the conventional configuration shown in FIGS. 6 and 7, no hydraulic pressure supply path is provided in the torque link 30. A hydraulic pipe 521 for supplying hydraulic pressure to the brake device 52 is disposed outside the torque link 30 along the torque link 30, and the hydraulic pipe 521 is intermediately disposed via a clamp 523. The torque link 30 is fixed. Such hydraulic piping 521 and the clamp 523 are equivalent to forming irregularities on the surface of the torque link 30, and the irregularities on the surface disturb the air flow and generate and increase air noise.

  On the other hand, in the landing gear 1 shown in FIGS. 1 and 2, since the hydraulic pressure supply paths 315, 325, 331, 341, and 351 are provided in the torque link 3, hydraulic piping and clamps outside the torque link 3 are connected. It can be omitted. As a result, it is possible to prevent the disturbance of the air flow due to the unevenness formed by the hydraulic piping or the clamp, which is advantageous for reducing the air noise. In particular, this configuration has an advantage that a fairing that covers the hydraulic piping and the clamp is unnecessary.

  In addition, you may replace a part of supply path provided in the torque link 3 with external piping as needed. For example, in the illustrated example, the supply path 341 is provided in the pivot shaft 34, but the supply path 341 in the pivot shaft 34 is omitted and the supply path 315 in the upper arm 31 and the supply path in the lower arm 32 are omitted. An external pipe connecting to 325 may be separately provided so as to bypass the pivot shaft 34. Even in this configuration, since the number of pipes and clamps exposed to the outside of the torque link 3 can be reduced, an effect of reducing air noise can be obtained accordingly. Similarly, instead of providing the supply paths 331 and 351 in the first mounting shaft 33 and / or the second mounting shaft 35, external piping that bypasses the first mounting shaft 33 and / or the second mounting shaft 35 is provided. May be. The hydraulic external piping is not limited to being provided at the shaft portion such as the pivot shaft 34 and the first and / or second mounting shafts 33 and 35, but may be provided at other locations.

  In the above configuration, the hydraulic pressure supply path provided in the torque link 3 and the brake device 52 are connected to each other by the external pipe 522. Instead of providing the external pipe 522, the torque link 3 The hydraulic pressure supply path provided inside and the brake device 52 may be connected to each other by an internal flow path provided in the structural member of the landing gear 1. That is, all the hydraulic pressure supply paths may be built in between the torque link 3 and the brake device 52. This configuration is advantageous in further reducing air noise because the external piping 522 can be omitted.

(Configuration to reduce or eliminate unevenness of torque link surface by incorporating signal lines, etc.)
In the above-described configuration, the hydraulic pressure supply path to the brake device 52 is provided inside the torque link 3. However, differently, various signal lines are provided inside the torque link 3, thereby the torque link 3. The number of signal lines arranged around 3 may be reduced or eliminated.

  As shown in FIG. 6, in the conventional configuration, for example, a signal line connected to a brake temperature sensor that detects the temperature of the brake device 52, a signal line connected to a WOW (Weight On Wheel) sensor, and a tire pressure sensor Various signal lines 524 such as a signal line to be connected are arranged around the torque link 30 along the torque link 30 as in the case of the hydraulic piping 521, and appropriate portions are provided via the clamps 523. It is fixed to the torque link 30. Therefore, similar to the hydraulic piping 521, these signal lines 524 (including the harness) and the clamp 523 also disturb the air flow flowing around the torque link 30 to generate and increase air noise.

  Therefore, these signal lines may be arranged inside the torque link. Specifically, a path for laying a signal line, which is equivalent to the above-described hydraulic pressure supply paths 315 and 325, may be provided inside the upper arm 31 and the lower arm 32 of the torque link 3 (see FIG. 3). A slip ring or the like is employed at a movable portion such as between the upper arm 31 and the first mounting shaft 33 and / or the pivot shaft 34 and between the lower arm 32 and the second mounting shaft 35 and / or the pivot shaft 34. May be. A part of the signal line may be external wiring instead of being provided inside the torque link 3 so as to bypass such a movable portion.

  The torque link 3 is not limited to such a signal line, and at least a part of a power line for supplying driving power to an actuator (for example, an electrohydraulic actuator: EHA) may be disposed. You may arrange | position at least one part of the cable for connecting between them mechanically.

  Furthermore, you may arrange | position in the torque link 3 combining two or more linear members arbitrarily selected from the signal line, the power line, and the cable. In addition, a hydraulic pressure supply path may be provided in the torque link 3, and at least one of the signal line, the power line, and the cable may be disposed in the torque link 3. The hydraulic pressure supply path and the linear member such as a signal line can be disposed in the torque link 3 so as to be parallel to each other, for example.

  Thus, by arranging various linear members in the torque link 3, it is possible to reduce or eliminate unevenness on the surface of the torque link 3, and to suppress disturbance of the air flow around the torque link 3. Alternatively, it is possible to suppress or prevent air noise.

(Configuration for reducing air noise in side braces)
In the landing gear 1, not only the configuration for reducing air noise is adopted for the torque link 3, but also the configuration for reducing air noise is adopted for the side brace 4. Hereinafter, a configuration for reducing air noise in the side brace 4 will be described.

  In the conventional landing gear 10, as shown in FIGS. 6 and 7, the upper link 410 of the side brace 40 has an intermediate portion 4130 between one end portion 4110 and the other end portion 4120 as a pair of flanges and a web between them. The web had a cross-sectional H-shape or I-shape, and a through-hole was formed in the web. In FIG. 6, the through hole is not visible. On the other hand, as shown in FIGS. 1 and 2, the upper link 41 of the side brace 4 in the landing gear 1 disclosed herein is an intermediate between the coupling portion 411 on one end side and the coupling portion 412 on the other end side. The part 413 has a circular cross section. That is, the intermediate portion 413 having a circular cross section that connects the connecting portion 411 on one end side and the connecting portion 412 on the other end side of the upper link 41 of the side brace 4 is configured by closing between both side edges. Has been. The upper link 41 having a circular cross section may be hollow, for example.

  The side brace is arranged so as to cross the air flow. The upper link 410 of the conventional configuration having a H-shaped or I-shaped cross section has a strong disturbance of the air flow that flows around it, and noise is likely to increase. It is effective for reducing air noise by suppressing the disturbance of the flowing air flow.

  As is clear from a comparison between FIG. 1 and FIG. 6, the lower link 420 in the side brace 40 of the conventional configuration is an intermediate portion 4230 between the coupling portion 4210 on one end side and the coupling portion 4220 on the other end side. In the web disposed between the pair of flanges, the through-hole 4231 is formed. The lower link 42 of this configuration is similar to the lower link 420 of the conventional configuration in that the coupling portion 421 on one end side and the other are connected. Although the intermediate portion 423 between the end-side coupling portion 422 has a pair of flanges and a web disposed therebetween, no through-hole is formed in the web. Similarly to the upper link 41, the lower link 42 is also configured such that an intermediate portion 423 that connects the coupling portion 421 on one end side and the coupling portion 422 on the other end side is closed between both side edge portions. It can be said that. By not forming the through hole in the web in this way, it is possible to suppress the disturbance of the flow of air flowing around the lower link 42, which is advantageous in suppressing or preventing air noise.

  Further, as shown in FIG. 6, the lock link 430 in the side brace 40 having the conventional configuration has a plurality of through holes 4330 formed in the second link member 4320, and thus the second link in the lock link 43 having the present configuration. As shown in FIG. 1, the member 432 is not formed with a through hole. Similarly to the upper link 41 and the lower link 42, the second link member 432 also has an intermediate portion that connects the coupling portion on the one end side and the coupling portion on the other end side to block between both side edge portions. It can be said that it is configured. Therefore, the air flow around the second link member 432 is prevented from being disturbed, which is advantageous in suppressing or preventing air noise.

  In addition, the shape of the intermediate part 413 in the upper link 41 of the side brace 4 is not limited to a circular cross section as shown in FIG. Various shapes can be employed. Specific examples of the cross-sectional shape of the intermediate portion 413 include an elliptical shape, a blade shape, and a streamline shape in addition to a circular shape. The upper link 41 having a shape capable of suppressing the disturbance of the air flow can also be referred to as an upper link integrated with a fairing. Further, the upper link 41 is not limited to a hollow shape.

  Further, the intermediate portion 413 in the upper link 41 of the side brace 4 is not limited to the above-described circular cross section, ellipse, wing shape, or streamline shape. For example, as in the conventional configuration shown in FIG. 6, the intermediate portion is configured in a H-shaped or I-shaped cross section having a pair of flanges and a web disposed between the flanges. It is good also as a structure which obstruct | occludes between a pair of flanges completely, without providing a through-hole. Even in such a configuration, it is possible to suppress or prevent the air noise by suppressing or preventing the disturbance of the air flow flowing around the upper link as compared with the conventional configuration.

  As shown in FIG. 1, in the upper link 41 of the side brace 4, a hydraulic supply / discharge path (that is, a hydraulic pipe 441) is disposed in the same manner as the torque link 3 described above (refer to FIG. 2). The hydraulic piping is not shown in FIG. The hollow upper link 41 is advantageous in incorporating the hydraulic piping 441. The hydraulic pipe 441 is for supplying and discharging hydraulic pressure to the down lock release actuator 44. Specifically, in the example of FIG. 1, the hydraulic piping 441 is introduced into the intermediate portion from two locations opposite to each other in the radial direction with respect to the circumferential surface of the circular intermediate portion of the upper link 41. ing. The place where the hydraulic pipe 441 is introduced is not limited to this position, and may be set to an appropriate place. Each of the two hydraulic pipes 441 extends along the axis of the upper link 41, and is led out from both side end surfaces of the pivot shaft that connects the upper link 41 and the lower link 42. The lead-out position of the hydraulic pipe 441 is not limited to this position, and can be set at an appropriate location. For example, the hydraulic pipe 441 may be extended to the inside of the lower link 42 from the inside of the upper link 41 and then led out to the outside at an appropriate position in the lower link 42. The configuration of the hydraulic piping between the upper link 41 and the pivot shaft, that is, the movable portion can be configured in accordance with the configuration of the hydraulic supply path of the movable portion of the torque link 3 described above. The hydraulic piping 441 led out from the side brace 4 is connected to the down lock release actuator 44.

  In the landing gear 10 of the conventional configuration, as shown in FIG. 6, the hydraulic pipe 4410 for supplying and discharging hydraulic pressure to the down lock release actuator 44 is disposed along the outer surface of the upper link 410, and a predetermined portion thereof is provided. It was fixed to the upper link 410 via a clamp. The hydraulic piping 4410 and the clamp exposed to the outside increase the unevenness of the surface of the side brace 40, thereby disturbing the air flow around the side brace 40 and generating and increasing air noise.

  On the other hand, disposing at least a part of the hydraulic piping 441 in the side brace 4 eliminates or reduces the unevenness of the surface of the side brace 4, so that the air flow around the side brace 4 is disturbed. It is possible to suppress or prevent air noise from being suppressed or prevented.

  In addition to providing the hydraulic piping 441 in the side brace 4, a linear member such as a wire including a signal line and a power line and a wire may be provided in the side brace 4. Further, both the hydraulic piping and the linear member may be disposed in the side brace 4.

  Further, the various configurations for reducing the air noise described above can be applied not only to the side brace but also to a drag brace that supports the pedestal in the direction of the axis.

1 landing gear 2 pedestal 3 torque link 31 upper arm (first arm member, link member)
311 Mounting part (joint part at one end)
312 Pivot (joint part on the other end)
313 Flange 314 Web 315 Supply path 32 Lower arm (second arm member, link member)
321 Mounting part (joint part at one end)
322 Pivot (joint part on the other end)
323 Flange 324 Web 325 Supply path 331 Supply path 341 Supply path 351 Supply path 4 Side brace (brace)
41 Upper link (link member)
411 Connecting portion 412 on one end side Connecting portion 413 on the other end side Intermediate portion 42 Lower link (link member)
421 Connecting portion 422 at one end side Connecting portion 423 at the other end side Intermediate portion 432 Second link member (link member)
44 Down-lock release actuator (hydraulic actuator)
441 Hydraulic piping (supply / discharge passage)
51 Wheel 52 Brake device

Claims (8)

Pedestals configured to support the wheels;
A link member attached to the pedestal,
The link member has a coupling portion on one end side, a coupling portion on the other end side, and an intermediate portion that couples the coupling portion on the one end side and the coupling portion on the other end side,
The intermediate part is an aircraft landing gear that is configured such that a gap between both side edges is closed. The aircraft landing gear according to claim 1,
The link member is a first and second arm member that is arranged on the front side or the rear side of the pedestal and that is pivotally coupled to each other to form a torque link,
The intermediate portions of the first and second arm members are respectively
A pair of flanges for connecting the coupling portion on the one end side and the coupling portion on the other end side; and
An aircraft landing gear arranged between the pair of flanges and including a web that closes between the flanges. The aircraft landing gear according to claim 2,
The brake device provided on the wheel further includes a supply path for supplying hydraulic pressure,
At least a part of the supply path is an aircraft landing gear provided inside the torque link. The aircraft landing gear according to claim 2 or 3,
An aircraft landing gear in which a linear member is disposed inside the torque link. The aircraft landing gear according to any one of claims 1 to 4,
The link member is a member that constitutes a brace whose base end portion is coupled to the pedestal, extends from the pedestal toward the body side, and whose distal end portion is coupled to the body.
The middle part of the link member constituting the brace is
A pair of flanges for connecting the coupling portion on the one end side and the coupling portion on the other end side; and
An aircraft landing gear arranged between the pair of flanges and including a web that closes between the flanges. The aircraft landing gear according to any one of claims 1 to 4,
The link member is a member that constitutes a brace whose base end portion is coupled to the pedestal, extends from the pedestal toward the body side, and whose distal end portion is coupled to the body.
The intermediate part of the link member constituting the brace is an aircraft landing gear whose cross-sectional shape is a circle, an ellipse, a wing, or a streamline shape. The aircraft landing gear according to claim 5 or 6,
A hydraulic actuator attached to the brace and for releasing the locked state of the leg column by the brace; and a supply / discharge path for supplying and discharging hydraulic pressure to the hydraulic actuator,
An aircraft landing gear, wherein at least part of the supply / discharge path is provided inside a link member constituting the brace. The aircraft landing gear according to any one of claims 5 to 7,
An aircraft landing gear in which a linear member is disposed inside a link member constituting the brace.