Device and method for restricting a moving part
The device uses an inertia-based mechanism with a pivoting member to restrain moving parts during high accelerations, addressing mass and response time issues in aerospace components.
Patent Information
- Application Number
- FR2023000461
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2023-01-18
- Publication Date
- 2025-10-31
- Estimated Expiration
- 2043-01-18
AI Technical Summary
Existing systems in aerospace applications, such as drones, missiles, rockets, and satellites, face issues with components like actuators and sensors due to significant accelerations, which can be detrimental and require non-reversible mechanisms like ball screws, increasing mass and response time.
A device using a mass that moves by inertia to restrain a moving part through a pivoting member, triggered by acceleration thresholds, minimizing mass and response time impact, with optional springs for preload and return mechanisms.
Effectively protects sensitive mechanisms from accelerations without significantly increasing mass or response time, ensuring reliable operation during high accelerations.
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Abstract
Description
Title of the invention: Device and method for restricting a moving part technical field
[0001] This disclosure relates to the protection of moving parts against shocks and accelerations and more particularly to a device and method of restraining a moving part during an acceleration along a first direction. Previous technique
[0002] Certain systems, particularly in the aerospace field, such as drones, missiles, rockets, satellites, or projectiles, can be subjected to significant temporary accelerations, especially during launches and catapult launches. These accelerations can be detrimental to components such as actuators or sensors, which include moving parts, and in particular moving parts arranged to move linearly along a travel path substantially aligned with the direction of actuation. Therefore, in such systems, it is generally preferable to use non-reversible mechanisms, such as ball screws, for linear actuators or cylinders. However, these mechanisms have the disadvantages of increasing mass and response time compared to electromagnetic actuators with direct linear actuation, for example. Description of the invention
[0003] The present disclosure aims to propose a device for restricting a moving part during acceleration intended to provide protection against accelerations or shocks to sensitive mechanisms such as actuators or sensors, without excessively increasing their mass and without affecting their response time under normal conditions.
[0004] According to a first aspect, this device may comprise a mass capable of moving by inertia between a first position and a second position, and a member capable of moving between a release position of the moving part when the mass is in said first position and a restrained position of the moving part when the mass is in said second position, said member being notably configured to contact a shoulder of the moving part in the restrained position. Thus, the simple inertia of the mass during acceleration can trigger the member used to restrain the moving part. The device may in particular be calibrated to restrain the moving part when the acceleration reaches a predetermined threshold, said predetermined threshold being, for example, 490.5 m / s² (50 G) or 981 m / s² (100 G).
[0005] This component may, in particular, be a lever capable of pivoting between the release position and the restricted position. Such a pivoting configuration has the advantage of limiting friction and therefore reaction time and the risk of jamming. However, alternative configurations, such as a sliding component between the release and restricted positions, are also conceivable.
[0006] The device may also include a first spring arranged to exert a preload on said component. In particular, in a first embodiment, the first spring may be arranged to exert the preload on said component towards the release position of the moving part. Thus, the component can be held by the first spring in the release position of the moving part as long as the mass is in its initial position before acceleration, and returned to this position as soon as the mass leaves its second position after acceleration. However, other configurations are also possible.Thus, in a second embodiment, the device may further include a second spring arranged to exert a preload on the mass, and in particular towards the initial position of the mass. The first spring may then be arranged to exert the preload on the component towards the restricted position of the moving part. The component can thus be held by the second spring, through the mass, in the position where the moving part is released before acceleration, be moved by the first spring towards the restricted position when the mass leaves its initial position under the effect of acceleration, and be returned by the second spring, through the mass, to the position where the moving part is released after acceleration. As an alternative to each of the first and second springs, other devices may be considered for exerting similar preloads, such as permanent magnets.
[0007] In order to limit the contact surfaces and therefore friction, the mass may have a round cross-section in at least one plane aligned with a direction of mass movement between the first and second positions, and in particular be cylindrical or even spherical. For the same reason, said component may include a convex contact surface with the mass. Other shapes, notably wedge-shaped, are however conceivable for the mass and / or the component.
[0008] A second aspect of this disclosure relates to a mechanism that may include a moving part and the restraining device described in the first aspect for restricting the moving part. The mechanism may, in particular, be an actuator configured to actuate a movement through the moving part, and specifically a linear actuator configured to actuate a translational movement through the moving part and / or an electromagnetic actuator. However, it is also conceivable that the mechanism may be of another type, for example, a sensor.
[0009] A third aspect of this disclosure relates to a method for restraining a moving part during acceleration along a first direction, which may include the inertial displacement of a mass from a first position to a second position and the displacement of a component from a release position of the moving part when the mass is in said first position to a restrained position of the moving part when the mass is in said second position. Brief description of the drawings
[0010] [Fig.1A] Fig.1A illustrates a linear electromagnetic actuator with a restraint device according to a first embodiment, at rest.
[0011] [Fig.1B] Fig.1B illustrates the actuator of Fig.1A, subjected to acceleration.
[0012] [Fig. 1C] [Fig. 1C] illustrates the actuator of Figures IA and IB in operation after acceleration.
[0013] [Fig.2A] Fig.2A illustrates a restricted device according to a second embodiment, at rest.
[0014] [Fig.2B] Fig.2B illustrates the restricted device according to the second embodiment, subjected to an acceleration. Description of the implementation methods
[0015] A linear electromagnetic actuator 10 with a restrictor device 100 according to a first embodiment is illustrated in Figures IA to IC. As illustrated, the actuator 10 may include a housing 11. This housing 11 may contain a fixed electromagnet 12. This electromagnet 12 may be annular and receive, in its central orifice, a movable part 13. This movable part 13 may include a ferromagnetic core 13a, such that the activation of the electromagnet 12 can actuate a movement along the direction of the central axis X of the electromagnet 12 through the movable part 13. The movable part 13 may also include a bushing 13b, integral with the ferromagnetic core 13a and having one or more shoulders 13c substantially perpendicular to the direction of the central axis X of the electromagnet 12.A spring 14 can be interposed between the housing 11 and the moving part 13 in order to return it to a basic position when the electromagnet 12 is inactive.
[0016] As illustrated, the restricting device 100 can be integral with the housing 11 of the actuator 10. This restricting device 100 can in particular include a mass 110, a member 120 for restricting the movement of the moving part 13 according to the position of the mass 110, and a return spring 130.
[0017] The restrictor device 100 may also include a gutter 140, in which the mass 110 can be received, to guide the latter between a first position illustrated in Figures IA and IC and a second position illustrated in [Fig. 1B], the mass 110 can move between these first and second positions by inertia as a function of an acceleration to which the actuator 10 would be subjected in the direction of an axis of the gutter 140 which can be, as illustrated, substantially parallel to the central axis X of the electromagnet 12 and therefore to the direction of actuation by the actuator 10. The mass 110 can in particular be spherical, as illustrated, in order to minimize the contact surface with this gutter 140, and therefore the friction in its movement between the said first and second positions.
[0018] As illustrated, the member 120 can, in particular, be a lever capable of pivoting, around a pivot 121 fixed to the housing 11, between a release position of the moving part 13, as illustrated in Figures IA and IC, and a restricted position of the moving part 13, as illustrated in [Fig. 1B]. The member 120 can have, at one end, a convex surface 122 for contact with the mass 110, in order to transmit an inertial force from the mass 110 to the member 120. At the opposite end, the member 120 can have a finger 123 arranged so as to contact a shoulder 13c of the moving part 13 in order to restrict its movement in the direction of the central axis X when the member 120 is in its restricted position of the moving part 13 illustrated in [Fig. 1B].In this restricted position, the lever arm L0 between the point of contact of the member 120 with the moving part 13 and the pivot 121 can be substantially greater than the lever arm L2 between the point of contact of the member 120 with the mass 110 and the pivot 121, in such a way that a mass 110 substantially less in mass than the moving part 13 can balance the opposing tilting torque exerted by the moving part 13, even after subtracting the restoring torque exerted by the spring 130.
[0019] The return spring 130 can be arranged to return the member 120 to its release position of the moving part 13 and, with it, the mass 110 to its initial position. The elasticity and preload of the spring 130, its lever arm L1 relative to the pivot 121, the mass 110, and the distance L2 from the pivot 121 to the point of contact of the mass 110 with the surface 122 can be calibrated so that the member 120 reaches its constraint position of the moving part 13 when the acceleration reaches a predetermined threshold, said predetermined threshold being, for example, 490.5 m / s² (50 G) or 981 m / s² (100 G).
[0020] Thus, during operation, an acceleration along the direction of the central axis X that exceeds the predetermined threshold can displace the mass 110 by inertia from its first position, illustrated in [Fig. 1A], to its second position, illustrated in [Fig. 1B]. During this displacement, the mass 110 can tilt the member 120, thus simultaneously displacing it from its position of release from the moving part 13, illustrated in [Fig. 1A], to its position of restricted movement of the moving part 13, illustrated in [Fig. 1B], against the restoring force exerted by the spring 130. In this restricted position, The component 120 can contact the moving part 13, thus restricting its inertial movement in the direction of acceleration. This prevents the moving part 13 from detaching from the electromagnet 12 during this acceleration.
[0021] When the acceleration ceases or decreases below the predetermined threshold, the spring 130 can return the member 120 to its position of release of the moving part 13, and with it the mass 110 to its first position, thus releasing the moving part 13 in translation along the direction of the central axis X. In this way, the moving part 13 can again move along the central axis X in response to the activation of the electromagnet 12, as illustrated in [Fig.1C].
[0022] Although, in this first embodiment, the movement of the member 120 towards its restricted position of the moving part 13 is directly actuated by the inertia of the mass 110, other embodiments are also conceivable, in which the movement of the member 120 towards its restricted position of the moving part 13 is not actuated, but only triggered by the movement of the mass 110 from its first position to its second position under acceleration.
[0023] Thus, in a second embodiment, illustrated in Figures 2A and 2B, in which the analogous elements are given the same reference numerals as in Figures IA to IC, the device 100 can comprise, in addition to a first spring 130 exerting a preload on the member 120, a second spring 150 exerting a preload on the mass 110 towards its first position in the groove 140. Unlike the first embodiment, in this second embodiment the preload exerted by the first spring 130 on the member 120 is exerted towards its restricted position of the moving part 13. The mass 110 can be arranged so as to lock, in its first position, the member 120 in its release position of the moving part 13, as illustrated in [Fig. 2A].The preload and elasticity of the second spring 150 and the mass 110 can be calibrated so that the mass 110 moves from its first position to its second position, as illustrated in [Fig. 2B], when the acceleration reaches a predetermined threshold, said predetermined threshold being, for example, 490.5 m / s² (50 G) or 981 m / s² (100 G). The first spring 130 can then actuate the displacement of the member 120 to its restricted position of the moving part 13, in which a finger 123 of the member is arranged to contact a shoulder 13c of the moving part 13 to restrict its movement in the direction of the acceleration.The lever arm L0 between the point of contact of the member 120 with the moving part 13 and the pivot 121 and the lever arm L1 of the first spring 130 with respect to the pivot 121 as well as the elasticity and preload of the spring 130 can be calibrated so as to ensure that the displacement of the moving part 13 in the direction of acceleration remains restricted by the member 120 even at the most. High accelerations are possible. Unlike the first embodiment, the member 120 may not automatically return to its release position from the moving part 13 when the acceleration ceases or decreases below the predetermined threshold. Means (not shown) for resetting the device 100 by returning the member 120 to its release position from the moving part 13 may, however, be incorporated into the device 100 according to this second embodiment.
[0024] Although the present invention has been described with reference to specific embodiments, it is evident that various modifications and changes can be made to these examples without departing from the general scope of the invention as defined by the claims. Furthermore, individual features of the various embodiments mentioned can be combined in additional embodiments. Therefore, the description and drawings should be considered in an illustrative rather than restrictive sense.
Claims
Demands
1. A device (100) for restricting a moving part (13) during acceleration, characterized in that it comprises: a mass (110) capable of moving by inertia from a first position to a second position, and a member (120) capable of moving from a release position of the moving part (13) when the mass (110) is in said first position to a restricted position of the moving part (13) when the mass (110) is in said second position.
2. Restricted device (100) according to claim 1, wherein said member (120) is a lever capable of pivoting between the release position and the restricted position.
3. A restraining device (100) according to any one of the preceding claims, further comprising a first spring (130) arranged to exert a preload on said member (120).
4. A restraint device (100) according to claim 3, wherein the first spring (130) is arranged to exert preload on said member (120) towards the release position of the moving part (13).
5. A restraining device (100) according to claim 3, further comprising a second spring (150) arranged to exert a preload on the mass (110).
6. Restriction device (100) according to claim 5, wherein the second spring (150) is arranged to exert preload on the mass (110) towards the first position of the mass (110) and the first spring (130) is arranged to exert preload on said member (120) towards the restricted position of the moving part (13).
7. A restraint device (100) according to any one of the preceding claims, wherein the mass (110) has a round cross-section in at least one plane aligned with a direction of movement of the mass (110) between the first and second positions.
8. Restricted device (100) according to claim 7, wherein the mass (110) is spherical.
9. A restraining device (100) according to any one of the preceding claims, wherein said member (120) comprises a convex surface (122) in contact with the mass (110).
10. A restricted device (100) according to any one of the preceding claims, wherein said member (120) is configured to contact a shoulder (13c) of the movable part (13) in the restricted position.
11. A restraining device (100) according to any one of the preceding claims, calibrated to restrain the moving part (13) when the acceleration reaches a predetermined threshold, said predetermined threshold being for example 490.5 m / s2 (50 G) or 981 m / s2 (100 G).
12. Mechanism comprising a moving part (13) and the restraining device (100) according to any one of claims 1 to 11 for restraining the moving part (13).
13. Mechanism according to claim 12, characterized in that the mechanism is an actuator (10) configured to actuate a movement through the moving part (13).
14. Mechanism according to claim 13, characterized in that the actuator (10) is a linear actuator configured to actuate a translational movement through the moving part (13).
15. A method for restraining a moving part (13) during acceleration along a first direction, comprising the following steps: displacement of a mass (110) by inertia from a first position to a second position; and displacement of a member (120) from a release position of the moving part (13) when the mass (110) is in said first position to a restrained position of the moving part (13) when the mass (110) is in said second position.