Latch warning device

Abstract

A latch warning device is used for indicating a locking state and an unlocking state of a fan cover of an aircraft, and comprises a plunger latch arranged on the fan cover of the aircraft; the base is provided with a limiting device and an indicating piece, and the limiting device is elastically connected to the base and connected with the plunger latch to move between an unlocking position and a locking position along with opening and closing of the plunger latch; the indicating piece is installed on the base through an elastic mechanism and can move between an indicating locking position and an indicating unlocking position relative to the base, when the limiting device is located at the unlocking position, the indicating piece is always biased in the indicating unlocking position by the elastic mechanism, and when the limiting device is located at the locking position, the indicating piece can be placed and abut against the limiting device. And the indication locking position is maintained. The latch warning device is simple in structure and clear in state indication.

Description

Technical Field

[0001] The present invention relates to the technical field of indication of locked and unlocked states of components of civil aircraft, and in particular to a latch warning device. Background Art

[0002] During aircraft operations, ground maintenance personnel are required to manually close the fan cover latch. However, in practice, the fan cover latch may not be closed, causing the fan cover to fall off during takeoff. Therefore, based on the traditional design of the fan cover latch, an additional warning prompt design is required.

[0003] In response to this, some fan cover latch alarm technology solutions have been developed.

[0004] One technical solution features an opening in the fan cover and a metal warning flag housed within it. When the latch is released, the metal warning flag extends and unfurls on the fan cover body to alert maintenance personnel. A mechanism, including a movable locking pin and a displacement amplification linkage, connects the warning flag and latch. Another technical solution requires opening the oil tank access door before opening the fan cover latch. A mechanical linkage inside the access door is manually pulled out, and the island-shaped skin on the outside of the latch is rotated to unlock the fan cover latch. Without the fan cover latch, the oil tank access door cannot be closed. This solution utilizes the fan cover's oil tank access door as a warning. Yet another technical solution features a latch with a warning handle at the 3 o'clock position on the fan cover body. When opening the fan cover, the handle is used to pull the latch out of the stopper. The handle then protrudes from the cover body, providing a warning.

[0005] However, all existing technical solutions have defects. The above-mentioned warning flag solution requires the use of a large number of matching movable locking pins and displacement amplification connecting rods, which brings about a weight impact. The above-mentioned warning solution of the oil tank maintenance cover sets a large number of mechanical structures at the oil tank maintenance cover, which brings additional operations when the maintenance cover needs to be opened to perform oil tank maintenance. In the above-mentioned warning handle solution, the warning pin is not linked to the original latch of the fan cover, and it is impossible to detect and confirm whether the latch is locked, so it cannot effectively achieve the purpose of warning the fan cover that the latch is not locked. In short, the existing mechanical devices for warning that the fan cover latch is not locked generally have problems such as heavy weight, complex structure, and poor maintainability.

[0006] Therefore, it is necessary to propose an improved latch warning device that can solve the problems and defects in the above-mentioned prior art. Summary of the Invention

[0007] The object of the present invention is to provide a latch warning device, which is provided with an indicator on the fan cover skin and uses a simple mechanism to link the latch of the fan cover with the indicator.

[0008] According to the present disclosure, a latch warning device is provided for indicating the locked and unlocked states of a fan cover of an aircraft. The device comprises: a latch disposed on the aircraft fan cover; a base on which a limiter and an indicator are mounted, wherein the limiter is elastically connected to the base and coupled to the latch so as to move between an unlocked position and a locked position as the latch opens and closes; the indicator is mounted to the base via an elastic mechanism and is movable relative to the base between a locked position and an unlocked position. When the limiter is in the unlocked position, the indicator is always biased by the elastic mechanism to the unlocked position, and when the limiter is in the locked position, the indicator rests against the limiter and remains in the locked position. The limiter is positioned in the unlocked position by coupling with the latch and in the locked position by coupling with the base; the limiter utilizes its own positioning state to simply link with the indicator, causing the indicator to indicate the latched state of the latch.

[0009] According to another aspect of the present disclosure, the limiting device includes a displacement device and a stop device, wherein the displacement device is connected to the latch via a coupling and to the base via an elastic portion, wherein the stop device includes an elastic member and a slider, wherein the elastic member is fixed to the base at one end and the slider is fixed at the opposite end, wherein the displacement device includes a groove extending coaxially with the stop device, the stop device rests in the groove so that the slider can slide in the groove, and wherein the slider of the stop device is biased against the blind end of the groove by the elastic member. In this way, the slider of the stop device can change its position as the displacement device moves between the locked position and the unlocked position.

[0010] According to another aspect of the present disclosure, the latch warning device further includes a displacement guide fixed to the base, wherein the displacement device is disposed in the displacement guide and slides along the length of the base. The displacement guide serves to limit the movement direction of the displacement device and can be provided as a guide rail device surrounding the displacement device.

[0011] According to another aspect of the present disclosure, the elastic portion and the coupling member are arranged on either side of the displacement device along the length of the base. Thus, the pulling force caused by closing the latch and the retracting force of the elastic portion are both in the longitudinal direction, without generating force components in other directions that could affect the movement path of the displacement device.

[0012] According to another aspect of the present disclosure, the coupling member is a flexible shaft or a rigid shaft. If a flexible shaft is used, when the latch is opened, the latch also pushes the flexible shaft upward, but the flexible shaft does not transmit this thrust to the displacement device, or transmits this thrust to the displacement device to a lesser extent. Therefore, the displacement device is mainly pulled to the unlocked position by the retracting force of the elastic portion. If a rigid shaft is used, the rigid shaft transmits the upward thrust from the latch to the displacement device, and can move the displacement device to the unlocked position together with the elastic portion.

[0013] According to another aspect of the present disclosure, when the latch is closed, the latch drives the connecting member to pull the displacement device to move in a first direction, the limit device moves to a locked position, and the elastic member is stretched; when the latch is opened, the elastic part retracts, pulling the displacement device to move in a second direction opposite to the first direction, and the limit device moves to an unlocked position.

[0014] According to another aspect of the present disclosure, the indicator member pivotally moves about a resilient mechanism between an indicating unlocked position and an indicating locked position, wherein the resilient mechanism tends to bias the indicator member in the indicating unlocked position.

[0015] According to another aspect of the present disclosure, the indicator member includes a protrusion, wherein, when the limit device is in the unlocked position, the protrusion is misaligned with the slider of the stop device; when the limit device is in the locked position, the protrusion and the slider of the stop device can abut against each other, and the protrusion prevents the elastic mechanism from biasing the indicator member toward indicating the unlocked position.

[0016] According to another aspect of the present disclosure, the elastic mechanism includes a torsion spring.

[0017] According to another aspect of the present disclosure, the base includes an elongated opening through which the indicator member pivotally moves between an indicated unlocked position and an indicated locked position.

[0018] The latch warning device according to the present invention primarily uses an elastic limiting device to limit the position of the indicator. When the latch is closed, the latch pulls the limiting device to the locked position via a coupling. When the indicator pivots from the unlocked position to the locked position, it engages with the slider of the limiting device's stopper and is restrained by the slider in the locked position. When the latch is opened, the elastic member connected to the limiting device pulls the limiting device to the unlocked position due to its own rebound force. This displaces the slider of the limiting device's stopper, preventing the indicator from engaging with the slider. Consequently, the elastic mechanism connected to the indicator biases the indicator to the unlocked position. If the latch is not closed, the slider remains misaligned with the indicator, preventing the indicator from being restrained in the locked position and remaining biased by the elastic mechanism in the unlocked position. Therefore, the operator cannot rotate the indicator back to the locked position, indicating that the latch is not latched. The latch warning device of the present invention has a simple structure, convenient operation, and clear indication.

[0019] This summary is provided to introduce the concepts in a simplified form, which are further described in the detailed description below. This summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to limit the scope of the claimed subject matter. Other aspects and advantages of the present invention will become apparent from the following detailed description of the embodiments and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] For a more complete understanding of the present disclosure, reference may be made to the following description of exemplary embodiments considered in conjunction with the accompanying drawings. The accompanying drawings are not intended to limit the present disclosure to the specific embodiments depicted therein and are not necessarily to scale. In the drawings:

[0021] Figure 1 is a rear perspective view of a latch warning device according to a preferred embodiment of the present invention, wherein the latch is closed and the indicator is in an indicating locked position;

[0022] Figure 2 is a rear perspective view of a latch warning device according to a preferred embodiment of the present invention, wherein the latch is open and the indicator is in an unlocked position;

[0023] Figure 3 yes Figure 1 and Figure 2 A front perspective view of the warning portion of the latch warning device, wherein the stop device and the indicator are not shown;

[0024] Figure 4 yes Figure 1 and Figure 2 A front perspective view of the warning portion of the latch warning device, showing the stop device and not showing the indicator;

[0025] Figure 5 yes Figure 1 and Figure 2 A rear view of the warning portion of the latch warning device, wherein the indicator is in the indicating locked position; and

[0026] Figure 6 yes Figure 1 and Figure 2 A rear perspective view of the warning portion of the latch warning device, wherein the indicator is in an unlocked position.

[0027] Reference Signs List

[0028] 100 Latch warning device

[0029] 200 latch

[0030] 201 Locking pin

[0031] 300 Warning Department

[0032] 1 base

[0033] 11 Narrow opening

[0034] 2 Limiting device

[0035] 21 Elastic part

[0036] 3 indicators

[0037] 31 Elastic mechanism

[0038] 32 bumps

[0039] 4 Displacement device

[0040] 41 grooves

[0041] 42 Blind End

[0042] 5 Stop device

[0043] 51 elastic parts

[0044] 52 Sliders

[0045] 6 Connectors

[0046] 7 Displacement guide

[0047] 71 longitudinal side

[0048] 72 front wing

[0049] 73 rear wing DETAILED DESCRIPTION

[0050] The following description of the present invention with reference to the accompanying drawings shows specific embodiments in which the present invention may be practiced. The embodiments are intended to fully describe the various aspects of the present invention in detail so that those skilled in the art can implement the present invention. Other embodiments may be utilized and may be changed without departing from the scope of the present invention. Therefore, the following description of the specific embodiments should not be considered restrictive. The scope of the present invention is limited only by the appended claims and the full range of equivalents encompassed by the claims. The same reference numerals are used throughout the drawings and the specific embodiments to refer to the same or similar components.

[0051] The "upper" and "lower" herein refer to the working positions relative to the latch warning device 100, especially the warning portion 300 (e.g., Figure 3 and Figure 4"Front" and "rear" are relative terms used to describe other components of the warning unit 300 relative to the indicator 3. For example, components located at the rear are closer to the indicator 3 than components located at the front. In the operating position of the warning unit 300, the length of the base 1 extends vertically up and down. Therefore, "longitudinal" is defined as a direction parallel to the length of the base 1, i.e., upward or downward; and "transverse" is defined as a horizontal direction perpendicular to the longitudinal direction.

[0052] Figure 1 and Figure 2 The latch warning device 100 is shown with the latch 200 closed and with the latch 200 open. The latch warning device 100 generally comprises a latch 200 having a locking pin 201, a warning portion 300, and a coupling member 6 coupling the latch 200 to the warning portion 300. As the latch 200 is closed, its locking pin 201 pulls the coupling member 6 in a first, generally downward direction. As the latch 200 is opened, its locking pin 201 moves in a second, generally upward direction opposite to the first direction, weakening or releasing the pulling force applied to the coupling member 6 in the first direction, thereby allowing the displacement device 4 of the warning portion 300 to pull the coupling member 6 in the second direction.

[0053] Please note that Figure 1 and Figure 2 The length of the coupling member 6 shown is not its actual length, but is shortened for clarity. The coupling member 6 can be of any length, depending on the distance between the latch 200 and the warning portion 300, and is not limited to the length shown relative to the latch 200 and the warning portion 300 in the drawings.

[0054] Figures 3 to 6 The warning part 300 of the latch warning device 100 is shown in detail. As shown in the drawings, the warning part 300 comprises a base 1, a limiting device 2 mounted on the base 1 and an indicator 3.

[0055] The limiting device 2 is elastically connected to the base 1 through the elastic portion 21 and is connected to the latch 200 through the coupling 6 so that it can move between the unlocked position and the locked position as the latch 200 is opened and closed. Figure 4 The illustrated device includes a displacement device 4 and a stopper 5. The displacement device 4 is connected to the base 1 via elastic portions 21 and to the latch 200 (preferably, to the end of the latch pin 201 of the latch 200) via connectors 6 on either side of the base 1 along its length (longitudinal direction). The latch warning device 100 also has a displacement guide 7 fixed to the base 1. This guide 7 encloses the displacement device 4, restricting it to sliding up and down only along the length of the base 1.

[0056] In this preferred embodiment, the displacement guide 7 is as follows Figure 2 and Figure 4 The shape shown is similar to the shape of "η" rotated 90 degrees, specifically, it has a longitudinal side 71 extending longitudinally parallel to the length of the base 1, and a front wing 72 and a rear wing 73 extending parallel to each other from the longitudinal side 71 toward the base 1. The longitudinal side 71 abuts against the displacement device 4, sandwiching the displacement device 4 between the longitudinal side 71 of the displacement guide 7 and the base 1; the front wing 72 is as shown in FIG. Figure 2 The rear wing 73 does not extend to the base 1 but leaves space for installing the stop device 5.

[0057] Thus, when the latch 200 is closed, it drives the coupling member 6 via the locking pin 201, pulling the displacement device 4 in a first, downward direction to the locked position, causing the elastic portion 21 to be stretched by the tension. When the latch 200 is opened, the locking pin 201 moves in a second, upward direction opposite to the first direction, in turn pushing the coupling member 6 in the second direction. At this time, the elastic portion 21, due to its rebound force, pulls the displacement device 4 back in the second direction to the unlocked position.

[0058] The elastic portion 21 may be a spring, while the coupling 6 may be a flexible shaft or a rigid shaft. In this preferred embodiment, the coupling 6 is a flexible shaft. Therefore, when the locking pin 201 moves upward, the upward thrust applied to the coupling 6 is not transmitted to the displacement device 4, or is transmitted to a lesser extent. Therefore, the elastic force of the elastic portion 21 is primarily used to pull the displacement device 4 to the unlocked position. Alternatively, the coupling 6 may be a rigid shaft. In this case, when the locking pin 201 pushes on the coupling 6, the coupling 6 can also transmit force, thereby enabling the coupling 6 to move the displacement device 4 in the second direction together with the elastic portion 21.

[0059] like Figure 3 As shown, the displacement device 4 includes a groove 41, which extends downward from the upper end of the displacement device 4 but does not reach the lower end of the displacement device 4, that is, it has a blind end 42 located below. Figure 4 The illustrated embodiment includes a resilient member 51 and a slider 52. The resilient member 51 is secured to the base 1 at one end and the slider 52 is secured to the opposite end. The resilient member 51 extends coaxially with the groove 41, enabling the slider 52 to slide within the groove 41. The resilient member 51 is positioned to bias the slider 52 against the blind end 42 of the groove 41 at all times, regardless of whether the displacement device 4 is in the unlocked or locked position. Thus, the slider 52 remains stationary relative to the displacement device 4 and changes its position relative to the base 1 as the displacement device 4 moves between the unlocked and locked positions. Preferably, the resilient member 51 comprises a spring.

[0060] The latch warning device 100 further includes an indicator 3. The indicator 3 is mounted to the base 1 by means of an elastic mechanism 31 and can move relative to the base 1 between an indicating locked position and an indicating unlocked position. The elastic mechanism 31 is located near the upper side of the base 1 and preferably comprises a torsion spring. The base 1 further includes a longitudinally extending slit 11 to allow the indicator 3 to pass through the slit 11. Figure 5 The unlocked position shown is the same as Figure 6 The pivotal movement between the indicated locked positions is achieved by means of a resilient mechanism 31. The resilient mechanism 31 tends to bias the indicator member 3 to the indicated unlocked position, so that if no external force holds the indicator member 3 in the indicated locked position, the indicator member 3 will always be in the indicated unlocked position.

[0061] like Figure 2 As shown, the indicator 3 has a projection 32 with two parallel inclined surfaces.

[0062] When the latch 200 is closed and the stopper 2 is in the locked position, while the operator is pivoting the indicator member 3 from the unlocked position to the locked position, the projection 32 of the indicator member 3 may contact the slider 52 of the stopper 5, and then one of its inclined surfaces may push the slider 52 upward until the projection 32 pivots away from the slider 52. At this point, the elastic member 51 of the stopper 5, due to its rebound force, pushes the slider 52 downward again, causing it to abut against the blind end 42 of the groove 41 of the displacement device 4. After the indicator member 3 reaches the locked position, the pivoting force applied to the indicator member 3 is withdrawn, and the indicator member 3 pivots toward the unlocked position due to the biasing force of the elastic member 31. This allows the slider 52 to re-engage and abut against the projection 32 of the indicator member 3 with its other inclined surface. The projection 32 of the indicator member 3 pivoted toward the unlocked position tends to push the slider 52 of the stop device 5 downward, but the slider 52 cannot continue to move downward because it has abutted against the blind end 42 of the groove 41 of the displacement device 4. Therefore, the projection 32 resists the biasing force of the elastic mechanism 31 and maintains the indicator member 3 in the locked position.

[0063] As the latch 200 opens, the limiting device 2 moves toward the unlocked position. As described above, the slider 52 of the stopper 5 moves upward along with the displacement device 4 toward the unlocked position. Consequently, the slider 52 moves upward relative to the protrusion 32 of the indicator member 3. When the slider 52 is misaligned with the protrusion 32 of the indicator member 3 and no longer exerts abutting force against it, the biasing force of the elastic mechanism 31 pivots the indicator member 3 to the indicated unlocked position.

[0064] With the latch 200 open, the operator pivots the indicator member 3 to the indicated locked position. Because the slider 52 of the stopper 5 has already reached the unlocked position along with the displacement device 4 and is misaligned with the projection 32 of the indicator member 3, it can no longer contact and abut against the projection 32 of the indicator member 3. Consequently, the indicator member 3 cannot be prevented from pivoting to the indicated unlocked position due to the biasing force of the elastic mechanism 31. Therefore, if the latch 200 is not closed, the indicator member 3 cannot remain in the indicated locked position, and the operator will naturally be aware that the latch 200 is not latched into place.

[0065] Preferably, the warning portion 300 is disposed within the aircraft's fan cover. When the indicator member 3 is in the unlocked position, the warning portion protrudes from the cover. When the indicator member 3 is in the locked position, the warning portion is flush with the cover. Of course, the warning portion 300 may be disposed in any suitable location, as long as the indicator member 3 is clearly noticeable when in the unlocked position and does not affect the aircraft's aerodynamic shape when in the locked position.

[0066] The latch warning device 100 of the present invention mainly uses an elastic device to link the latch and the indicator, ensuring that it can accurately indicate whether the latch is latched in place while having a simple structure and convenient operation, solving the technical problems of the latch warning solution in the prior art, such as heavy weight, complex structure and poor maintainability.

[0067] As used herein, the terms "comprises," "comprising," "including," "having," or any further variations thereof, are intended to cover a non-exclusive inclusion. For example, a method, article, or apparatus that comprises a list of elements is not necessarily limited to only those elements but may include other elements not expressly listed or inherent to such method, article, or apparatus.

[0068] The present invention is not limited to the above-described embodiments, which are merely illustrative and non-restrictive. Those skilled in the art, guided by the present invention, may make any possible changes and modifications without departing from the spirit of the present invention and the scope of protection of the claims. Therefore, any modifications, equivalent variations, and modifications made to the above-described embodiments in accordance with the technical essence of the present invention, without departing from the content of the technical solution of the present invention, shall fall within the scope of protection defined by the claims of the present invention.

Claims

1. A latch warning device for indicating the locked and unlocked states of a fan cover of an aircraft, comprising: a latch disposed on a fan cover of the aircraft; A base is provided with a limit device and an indicator, wherein: The limiting device is elastically connected to the base and coupled to the latch to move between an unlocked position and a locked position as the latch is opened and closed; The indicator is mounted on the base by means of an elastic mechanism and can move relative to the base between an indicating locked position and an indicating unlocked position. Wherein, when the limiting device is in the unlocking position, the indicator is always biased in the indicating unlocking position by the elastic mechanism. When the stop device is in the locked position, the indicator member can rest against the stop device and be maintained in the indicated locked position.

2. The latch warning device according to claim 1, characterized in that: The limiting device includes a displacement device and a stop device, wherein the displacement device is connected to the latch by a coupling member and is connected to the base by an elastic portion. The stop device includes an elastic member and a slider, wherein one end of the elastic member is fixed to the base, and the other end thereof is fixed to the slider. The displacement device includes a groove extending coaxially with the stop device, and the stop device is placed in the groove so that the slider can slide in the groove. And wherein, the slider of the stop device is biased by the elastic member against the blind end of the groove.

3. The latch warning device according to claim 2, characterized in that: The latch warning device further includes a displacement guide fixed to the base, wherein the displacement device is disposed in the displacement guide and slides along the length direction of the base.

4. The latch warning device according to claim 3, characterized in that: The elastic portion and the coupling member are arranged on both sides of the displacement device along the length direction of the base.

5. The latch warning device according to any one of claims 2 to 4, characterized in that: The coupling is a flexible shaft or a rigid shaft.

6. The latch warning device according to claim 4, characterized in that: When the latch is closed, the latch drives the coupling member to pull the displacement device to move in the first direction, the limiting device moves to the locking position, and the elastic part stretches; When the latch is opened, the elastic portion retracts, pulling the displacement device to move in a second direction opposite to the first direction, and the limiting device moves to the unlocking position.

7. The latch warning device according to claim 1 or 2, characterized in that: The indicator member is pivotally movable about the resilient mechanism between the indication unlocked position and the indication locked position, wherein the resilient mechanism tends to bias the indicator member in the indication unlocked position.

8. The latch warning device according to claim 7, wherein: The indicator comprises a convex block, wherein: When the limiting device is in the unlocking position, the protrusion is misaligned with the slider of the stopping device; When the limiting device is in the locking position, the protrusion and the slider of the stopping device can abut against each other, and the protrusion prevents the elastic mechanism from biasing the indicator member toward the unlocking indication position.

9. The latch warning device according to claim 7, wherein: The elastic mechanism includes a torsion spring.

10. The latch warning device according to claim 7, wherein: The base includes an elongated opening through which the indicator member pivotally moves between the indicated unlocked position and the indicated locked position.

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