Patent Description:
Many aircraft have at least one cargo bay designed to receive cargo. Such cargo bays include cargo loading systems that include rollers located on a floor of the cargo bay to provide conveyance for moving a unit load device (ULD) or other cargo through the cargo bay. After cargo has been loaded into the cargo bay, it may be desirable to restrain the cargo. Some ULDs, for example, military pallets, have pockets along the sides of the pallets. Restraints may be located in the pockets to provide longitudinal and/or lateral restraint. Such restraint reduces the likelihood of cargo shifting relative to the cargo bay during taxi, takeoff, flight, and landing. Current restraint actuation systems are generally configured to deploy and to stow all the restraints simultaneously. Such actuating scheme tends to limit the number of available cargo load configurations. <CIT> relates to a cargo restraint system.

In various embodiments, a restraint assembly actuation system for use with a cargo restraint system is provided comprising a drive shaft assembly comprising a first outer tube and an inner shaft, wherein the first outer tube and the inner shaft are disposed coaxially about an axis and a first restraint coupled to the first outer tube, wherein the first outer tube is configured to rotate the first restraint about the axis to a raised position to restrain a cargo load.

The first restraint comprises a head configured to engage with the cargo load.

The first restraint comprises a shroud coupled to the outside of the first outer tube, and a plunger rod coupled to the shroud and the head.

In various embodiments, the shroud comprises a notch opening configured to receive a notch coupled to the inner shaft and the shroud at a first opening of the first outer tube.

In various embodiments, the first restraint further comprises the head defining a plunger channel, a plunger including the plunger rod and a plunger lever, the plunger rod being located, at least, partially in the plunger channel, a plunger torsion spring configured to apply a first biasing load to the plunger lever, and a compression spring configured to bias a first end of the plunger away from an upper surface of the head. In various embodiments, a drive cap located around the first end of the plunger rod. In various embodiments, a drive cap located around the first end of the plunger rod. In various embodiments, the shroud defines a plunger opening configured to receive the first end of the plunger rod. In various embodiments, the shroud includes a protrusion extending radially outward from an outer circumferential surface of the shroud. In various embodiments, a second outer tube is coupled to the inner shaft and configured to rotate with the inner shaft. In various embodiments, a second restraint is coupled to the second outer tube, wherein the second outer tube is configured to rotate the second restraint about the axis to a raised position to restrain the cargo load. In various embodiments, the second outer tube is located aft of the first outer tube.

In various embodiments, a coaxial actuator assembly is provided comprising a drive shaft assembly comprising a first outer tube and an inner shaft, wherein the first outer tube and the inner shaft are disposed coaxially about an axis, a first outer tube actuator assembly coupled to the drive shaft assembly, a first actuator tube disposed within the first outer tube actuator assembly and coupled to the first outer tube, wherein the first actuator tube comprises a first actuator opening and a second actuator opening, each disposed in the first actuator tube, a first spring loaded plunger configured to be disposed in at least one of the first actuator opening or the second actuator opening, and a first actuator lever coupled to the first spring loaded plunger, the first actuator lever configured to translate the first spring loaded plunger at least one of in and out the first actuator opening and the second actuator opening, and a first geometric gripping surface coupled to the first outer tube actuator assembly configured to drive rotation of the first outer tube. In various embodiments, the first outer tube rotates coaxially about the axis in response to the first geometric gripping surface driving rotation of the first outer tube. In various embodiments, an inner shaft actuator assembly is coupled to the drive shaft assembly, a second actuator tube disposed within the inner shaft actuator assembly and coupled to the inner shaft, wherein the second actuator tube comprises a first actuator opening and a second actuator opening each disposed in the second actuator tube, a second spring loaded plunger configured to be disposed in the first actuator opening or the second actuator opening, and a second actuator lever coupled to the second plunger, configured to translate the second plunger at least one of in and out the first actuator opening and the second actuator opening, and a second geometric gripping surface coupled to the inner shaft actuator assembly and configured to drive rotation of the inner shaft. In various embodiments, the inner shaft rotates in response to the second geometric gripping surface driving rotation of the inner shaft.

In various embodiments, a restraint assembly actuation system is provided comprising a drive shaft assembly comprising a first outer tube and an inner shaft, wherein the first outer tube and the inner shaft are disposed coaxially about an axis, a coaxial actuator assembly comprising a first outer tube actuator assembly coupled to the drive shaft assembly, a first actuator tube disposed within the first outer tube actuator assembly and coupled to the first outer tube, wherein the first actuator tube comprises a first actuator opening and a second actuator opening each disposed in the first actuator tube, a first spring loaded plunger configured to be disposed in at least one of the first actuator opening or the second actuator opening, a first actuator lever coupled to the first spring loaded plunger, configured to translate the first spring loaded plunger at least one of in and out the first actuator opening and the second actuator opening, and a first geometric gripping surface coupled to the first outer tube actuator assembly and configured to drive rotation of the first outer tube, a second outer tube coupled to the inner shaft, and a first restraint assembly actuation system comprising a first restraint coupled to the first outer tube, wherein the first outer tube is configured to rotate the first restraint about the axis to a raised position to restrain a cargo load. In various embodiments, a second restraint is coupled to the second outer tube. In various embodiments, the second outer tube is configured to rotate the second restraint about the axis to the raised position to restrain the cargo load. In various embodiments, an inner shaft actuator assembly is coupled to the drive shaft assembly, a second actuator tube disposed within the inner shaft actuator assembly and coupled to the inner shaft, wherein the second actuator tube comprises a first actuator opening and a second actuator opening each disposed in the second actuator tube, a second spring loaded plunger configured to be disposed within at least one of the first actuator opening or the second actuator opening, and a second actuator lever coupled to the second plunger, configured to translate the second plunger at least one of in and out the first actuator opening and the second actuator opening, and a second geometric gripping surface coupled to the inner shaft actuator assembly configured to drive rotation of the inner shaft. In various embodiments, a plurality of forward restraints is coupled to the first outer tube and configured to be actuated by the first outer tube, and a plurality of aft restraints coupled to the second outer tube and configured to rotate coaxially with the second outer tube.

The detailed description of exemplary embodiments herein makes reference to the accompanying drawings, which show exemplary embodiments by way of illustration and their best mode. While these exemplary embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, it should be understood that other embodiments may be realized and that logical, chemical, and mechanical changes may be made without departing from the scope of the disclosure. For example, the steps recited in any of the method or process descriptions may be executed in any order and are not necessarily limited to the order presented. Also, any reference to attached, fixed, connected or the like may include permanent, removable, temporary, partial, full and/or any other possible attachment option.

The present disclosure provides a restraint assembly actuation system for aircraft cargo that, in various embodiments, utilizes a coaxial actuator assembly to actuate (e.g., using any appropriate motion or combination of motions) one or more restraints from a raised (or deployed) position to a stowed position. In accordance with various embodiments, the restraint assembly actuation system includes a drive shaft assembly comprising a first outer tube and an inner shaft disposed coaxially about an axis. In various embodiments, the inner shaft can be another tube and not a solid shaft. Multiple tubes may be disposed in the system coaxially about the axis without a solid inner shaft. In various embodiments, a first restraint or a plurality of first restraints may be coupled to a first outer tube. The cargo restraint system, in various embodiments, also comprises one or more coaxial actuator assemblies. A coaxial actuator assembly, in various embodiments, comprises a first outer tube actuator assembly coupled to the drive shaft assembly. The first outer tube actuator assembly, in various embodiments, controls rotation of the first outer tube located about the axis. Translation of the first restraint or a plurality of first restraints may be controlled by rotation of the first outer tube.

In accordance with various embodiments, a coaxial actuation assembly may comprise an inner shaft actuator assembly configured to control rotation of the inner shaft. At or near an aft end of the inner shaft, in various embodiments, an extender tube may be coupled to the inner shaft. A second outer tube may be coupled to the inner shaft at the extender tube, such that rotation of the inner shaft is translated to the second outer tube. Translation of a second restraint or a plurality of second restraints may be controlled by rotation (e.g., actuation) of the second outer tube. Allowing the restraints to be actuated as in at least two groups allows for more flexible control options than a single actuation system that actuates all restraints at once, while increasing the number of available restraining configurations throughout the cargo deck.

<FIG> illustrates an aircraft <NUM> with cargo <NUM> being loadable through a loading door <NUM> of the aircraft <NUM>. Cargo <NUM> may be loaded through loading door <NUM> and onto a cargo deck <NUM>. <FIG> illustrates cargo deck <NUM>. An X-Y-Z axis is shown in various drawings to illustrate various orientations of components. Cargo deck <NUM> includes a cargo deck floor <NUM>, which may be formed by one or more panels <NUM> that are coupled to various structural components of aircraft <NUM> (e.g., to beams, floors, etc.).

In accordance with various embodiments, <FIG> illustrates cargo deck <NUM> includes a restraint assembly actuation system <NUM>. Stated differently, restraint assembly actuation system <NUM> may be installed along cargo deck <NUM>. Cargo deck <NUM> may also include a cargo loading system <NUM> comprising a plurality of freely rotating conveyance rollers and/or powder drive units (PDUs) mounted in the cargo deck <NUM> to define the conveyance plane. Cargo loaded onto the aircraft cargo deck <NUM> can be moved throughout the cargo deck <NUM> using the cargo loading system <NUM>.

Restraint assembly actuation system <NUM> may be used to restrain cargo (e.g., unit load devices (ULDs)) within/relative to the cargo deck <NUM>. The restraint assembly actuation system <NUM> may include a plurality of first restraints 102a, one or more second restraints <NUM>, and a plurality of third restraints <NUM>. In various embodiments, the first restraints <NUM> may be referred to as X-restraints as they may restrict cargo from translating in the X (or longitudinal) direction. The second restraints <NUM> may be referred to as Z-restraints as they may restrict cargo from translating in the Z (e.g., vertical) direction. The third restraints <NUM> may be referred to as YZ-restraints as they may restrict translation of cargo in the Z (e.g., vertical) direction and the Y (e.g., lateral) direction. However, one skilled in the art will realize that the restraints <NUM>, <NUM>, <NUM> may be used to restrain cargo in any other directions (e.g., the first restraints <NUM> may restrain cargo in the Y direction). The restraint assembly actuation system <NUM> may include a coaxial actuator assembly <NUM>. A control region <NUM> of coaxial actuator assembly <NUM> may be located, for example, proximate loading door <NUM>, a forward end of the aircraft, and/or at any other location that may be readily accessible to crew responsible for loading cargo into cargo deck <NUM>. As described in further detail below, various components of coaxial actuator assembly <NUM> may be located under panels <NUM>. Coaxial actuator assembly <NUM> is configured to control the actuation of the first restraints <NUM>. In this regard, coaxial actuator assembly <NUM> may be employed to translate first restraints <NUM> between a raised position and a stowed position. In various embodiments, coaxial actuator assembly <NUM> may also control actuation of the second restraints <NUM> and/or the third restraints <NUM>.

<FIG> illustrates how the various restraints of restraint assembly actuation system <NUM> may restrain a ULD <NUM>. As shown, the first restraint <NUM> may rest between tabs <NUM>, <NUM> of the ULD <NUM>, restricting movement of the ULD <NUM> in the X direction. The second restraint <NUM> may rest above tabs <NUM>, <NUM> of the ULD <NUM>, thus restricting movement of the ULD <NUM> in the Z direction. The third restraint <NUM> may rest adjacent and above the tab <NUM> of the ULD <NUM>, thus restricting movement of the ULD <NUM> in the Y and Z directions.

Referring now to <FIG>, additional details of a first restraint <NUM> are shown. As shown, first restraint <NUM> may be actuated between a raised position (as shown in <FIG>) and a stowed position (as shown in <FIG>). First restraint <NUM> may include a head <NUM> (also referred to herein as a restraint body) which may be both raised and stowed. In the raised position, the head <NUM> may extend above the cargo deck floor <NUM>. In the stowed position, the head <NUM> may fit within an orifice <NUM> formed in the cargo deck floor <NUM>. For example, panel <NUM> may define an orifice <NUM> configured to receive a head <NUM>. In the stowed position, a first surface <NUM> of head <NUM> may be relatively/substantially flush and/or planar with an upper surface <NUM> the panel <NUM>.

With momentary reference to <FIG>, restraint assembly actuation system <NUM> is further illustrated. Restraint assembly actuation system <NUM> comprises first group <NUM> of restraints 102a and second group <NUM> of restraints 102b. Restraint assembly actuation system <NUM> further comprises drive shaft assembly <NUM>. Drive shaft assembly <NUM> comprises inner shaft <NUM> and first outer tube <NUM>, which are coaxially disposed as described herein along axis A-A', with A representing the forward terminus of drive shaft assembly <NUM> and A' representing the aft terminus of drive shaft assembly <NUM>. Coaxial actuator assembly <NUM> is illustrated comprising inner shaft actuator assembly <NUM> and first outer tube actuator assembly <NUM>. Inner shaft <NUM> is coupled to inner shaft actuator assembly <NUM>, where inner shaft actuator assembly <NUM> is configured to rotate inner shaft <NUM> about axis A-A'. First outer tube <NUM> is coupled to first outer tube actuator assembly <NUM>, where first outer tube actuator assembly <NUM> is configured to rotate first outer tube <NUM> about axis A-A'.

First outer tube <NUM> is configured, as shown and described herein, to actuate restraints 102a. In that regard, rotation of first outer tube <NUM> imparted by first outer tube actuator assembly <NUM> causes actuation of restraints 102a. Restraints 102b, however, remain stationary and are thus not activated by rotation of first outer tube <NUM> imparted by first outer tube actuator assembly <NUM>. Rotation of inner shaft <NUM> imparted by inner shaft actuator assembly <NUM> causes actuation of restraints 102b. In that manner, first group <NUM> are separately actuated from second group <NUM>. Stated another way, restraint assembly actuation system <NUM> allows one group of restraints to be actuated independently of a second group of restraints.

In various embodiments, first outer tube <NUM> terminates along axis A-A'. Inner shaft <NUM> may be coupled to second outer tube <NUM>. Second outer tube <NUM> may be fixedly attached to inner shaft <NUM> such that rotation of inner shaft <NUM> rotates second outer tube <NUM>. In that regard, in various embodiments, inner shaft <NUM> rotates an extender tube such that second outer tube <NUM> rotates one revolution for every one revolution rotated by inner shaft <NUM>. Second outer tube <NUM> may be fixedly attached to inner shaft <NUM> by any suitable means, for example, by press fit, interference fit, fasteners, threaded engagement, radially disposed pins, and/or welding, brazing, or other metallurgical joinery. Second outer tube <NUM> may be coupled to inner shaft <NUM> via intermediary components, such as a collar or cylindrical clamp.

With reference to <FIG> and <FIG>, first restraint <NUM> is illustrated in the raised position. In <FIG>, panel <NUM> is removed to illustrate components of restraint assembly actuation system <NUM> that may be located under upper surface <NUM> of panel <NUM>. In various embodiments, first restraint <NUM> may include one or more roller(s). Rollers may protrude from side surfaces <NUM> of head <NUM>. Rollers may be spring loaded such that rollers retract into head <NUM>, against the bias of a spring, in response to a load (represented by arrow L1) being transmitted from ULD <NUM> into the roller and consequently first restraint <NUM>. First restraint <NUM> may be raised into (e.g., located within) a pocket <NUM> of ULD <NUM>. Pocket <NUM> may be defined by a flange <NUM> located about a perimeter of ULD <NUM>. In embodiments, load L1 may be transmitted from ULD <NUM> into first restraint <NUM>. The rollers may reduce friction between ULD <NUM> and first restraint <NUM> when first restraint <NUM> translates between the raised position (as shown in <FIG> and <FIG>) and the stowed position (as shown in <FIG>). In this manner, first restraint <NUM> may allow for lower release forces when moving from the raised position to the stowed position to release ULD <NUM>. Stated differently, forces reacting between ULD <NUM> and first restraint <NUM> are attenuated by the rollers to increase ease of movement of first restraint <NUM> (relative to ULD <NUM>) when moving between the raised position and the stowed position.

A mount <NUM> (<FIG>) may be coupled to panel <NUM> via fasteners <NUM>. Fasteners <NUM> can be washers and a bolt head, or any other suitable fastener. In accordance with various embodiments, a drive shaft assembly <NUM> may be located through, and may extend through, mount <NUM> and head <NUM>. Stated differently, mount <NUM> and head <NUM> may be located on, and/or mounted on, drive shaft assembly <NUM>. Mount <NUM> may be a stationary structure. Head <NUM> and drive shaft assembly <NUM> may rotate relative to mount <NUM>. Drive shaft assembly <NUM> includes a first outer tube <NUM> and an inner shaft <NUM>. First outer tube <NUM> is located about inner shaft <NUM> (e.g., first outer tube <NUM> and inner shaft <NUM> are coaxially disposed). In accordance with various embodiments, first outer tube <NUM> and inner shaft <NUM> may both coaxially rotate about an axis A-A'. However, first outer tube <NUM> rotates independently of inner shaft <NUM>. In this regard, rotation of inner shaft <NUM> may be performed independently from first outer tube <NUM> (i.e., rotation of inner shaft <NUM> does not cause or impart rotation/movement of first outer tube <NUM>) and rotation of first outer tube <NUM> may be performed independently from inner shaft <NUM> (i.e., rotation of first outer tube <NUM> does not cause or impart rotation/movement of inner shaft <NUM>).

In various embodiments, a lubricant may be applied to the outside of the inner shaft to reduce friction between the first outer tube and the inner shaft. The lubricant may comprise oil or grease. In various embodiments, the outside of the inner shaft or the inside of the first outer tube may be coated in polytetrafluoroethylene to reduce friction between the first outer tube and the inner shaft. In various embodiments, the inner shaft and/or the first outer tube may comprise a wear coating disposed on one or more surfaces to provide corrosion resistance and/or mitigation of friction or abrasion.

First restraint <NUM> may include one or more head torsion spring(s) <NUM>. Head torsion spring <NUM> is configured to bias head <NUM> toward the raised position or the stowed position. Stated differently, head torsion spring <NUM> is configured to bias head <NUM> in a first circumferential direction about axis A-A'. As described in further detail below, first restraint <NUM> includes a plunger <NUM> (<FIG>), which may engage first outer tube <NUM>, such that rotation of first outer tube <NUM> is transferred to head <NUM>. Stated differently, when the plunger <NUM> is in an engaged state, head <NUM> rotates with first outer tube <NUM>.

With reference to <FIG>, a cross-section view of first restraint <NUM>, taken along line <NUM>-<NUM> in <FIG>, is illustrated. In accordance with various embodiments, first restraint 102a includes a plunger <NUM>. In <FIG>, first restraint <NUM> is in the raised position and plunger <NUM> is in an engaged state. Plunger <NUM> includes a plunger rod <NUM> and a plunger lever <NUM>. Plunger rod <NUM> is configured to translate radially (i.e., perpendicular to axis A-A'). In this regard, plunger rod <NUM> translates toward and away from first outer tube <NUM>. In various embodiments, plunger rod <NUM> may located in a plunger channel <NUM> defined by head <NUM>. A compression spring <NUM> may be located about plunger rod <NUM>. Compression spring <NUM> may be compressed between a spring interference surface <NUM> of plunger rod <NUM> and a bushing <NUM> located about plunger rod <NUM>. In various embodiments, bushing <NUM> may be eliminated and compression spring <NUM> may be compressed between spring interference surface <NUM> of plunger rod <NUM> and a second spring interference formed by head <NUM>. Compression spring <NUM> biases a first end <NUM> of plunger rod in the radially inward direction (i.e., toward first outer tube <NUM> and axis A-A).

A pin <NUM> may be located through plunger rod <NUM> and plunger lever <NUM>. Pin <NUM> may be located proximate a second end <NUM> of plunger rod <NUM>. Second end <NUM> is opposite first end <NUM>. Plunger lever <NUM> may rotate about pin <NUM>. A plunger torsion spring <NUM> may be located about pin <NUM> and may apply a biasing load to plunger lever <NUM>. Plunger torsion spring <NUM> may bias plunger lever <NUM> in the first circumferential direction about pin <NUM>.

In accordance with various embodiments, a shroud <NUM> may be located about first outer tube <NUM>. Stated differently, an inner circumferential surface <NUM> of shroud <NUM> may define a tube channel configured to receive first outer tube <NUM>. In accordance with various embodiments, a plunger opening <NUM> is formed in the outer circumferential surface <NUM> of shroud <NUM>. Stated differently, shroud <NUM> defines plunger opening <NUM>. Plunger opening <NUM> is configured to receive first end <NUM> of plunger rod <NUM>. Locating plunger rod <NUM> in plunger opening <NUM> creates an interference between plunger rod <NUM> and shroud <NUM>, such that plunger rod <NUM> is prevented from translating relative to shroud <NUM>. In accordance with various embodiments, shroud <NUM> defines a notch opening (e.g., a bore) <NUM> configured to receive a notch <NUM>. First outer tube <NUM> may define a notch channel <NUM>. Notch <NUM> may be located through notch opening <NUM> and in notch channel <NUM>, in response to radially aligning notch opening <NUM> and notch channel <NUM>. Locating notch <NUM> in notch opening <NUM> and notch channel <NUM> rotationally couples shroud <NUM> and first outer tube <NUM>, such that rotation of first outer tube <NUM> about axis A-A' causes shroud <NUM> to rotate about axis A-A'. Inner shaft <NUM> is shown extending through axis A-A', axis A-A' being the common axis for both first outer tube <NUM> and inner shaft <NUM>.

Shroud <NUM> includes a protrusion <NUM>. Protrusion <NUM> extends radially outward from outer circumferential surface <NUM> of shroud <NUM>. A drive cap <NUM> may be located around first end <NUM> of plunger rod <NUM>, and between plunger rod <NUM> and head <NUM>. When plunger <NUM> is an engaged state (i.e., when plunger rod <NUM> is in plunger opening <NUM>), protrusion <NUM> may be located proximate and/or may abut drive cap <NUM>. When plunger <NUM> is the engaged state, rotation of first outer tube <NUM> about axis A-A' causes shroud <NUM> to rotate in the same direction about axis A-A' as first outer tube <NUM> due to the contact between notch <NUM> and first outer tube <NUM> and the contact between notch <NUM> and shroud <NUM>. The rotation of shroud <NUM> causes head <NUM> to rotate in the same direction about axis A-A' as first outer tube <NUM> due to the contact between protrusion <NUM> and drive cap <NUM>. In this regard, a rotational force is transferred from shroud <NUM> to head <NUM> via contact between protrusion <NUM> and drive cap <NUM>.

When plunger rod <NUM> is radially aligned with plunger opening <NUM>, compression spring <NUM> forces first end <NUM> of plunger rod <NUM> into plunger opening <NUM> (i.e., plunger is forced into the engaged state). When plunger rod <NUM> is located in plunger opening <NUM>, the location of second end <NUM> and pin <NUM> generate an interference between a first lever surface <NUM> of plunger lever <NUM> and a first lever interference surface <NUM> of head <NUM>. In accordance with various embodiments, plunger torsion spring <NUM> is configured to bias first lever surface <NUM> toward first lever interference surface <NUM>. The interference (e.g., contact) between first lever surface <NUM> and first lever interference surface <NUM> blocks, or prevents, further rotation of plunger lever <NUM> in the first circumferential direction about <NUM> (i.e., the inference overcomes the biasing load being applied by plunger torsion spring <NUM>). In the engaged state, plunger lever <NUM> may be located radially inward of an upper surface <NUM> of head <NUM>. In this regard, a distance plunger lever <NUM> and axis A-A' may be less than a distance between upper surface <NUM> and axis A-A'. Upper surface <NUM> may be approximately perpendicular to first surface <NUM> and side surfaces <NUM> (<FIG>). As used in the previous context only, "approximately" means ± <NUM>° from perpendicular. In accordance with various embodiments, the spring constant of compression spring <NUM> is great enough to overcome the biasing load applied by plunger torsion spring <NUM>.

With reference to <FIG>, a cross-section view of first restraint <NUM>, taken along line <NUM>-<NUM> in <FIG>, is illustrated, with first restraint <NUM> in the raised position and plunger <NUM> in a disengaged state. To translate plunger <NUM> from the engaged state (<FIG>) to the disengaged state (<FIG>), a load L2 is applied in a second circumferential about pin <NUM> (e.g., in a direction opposite the biasing force applied by plunger torsion spring <NUM>). The load L2, along with an interference between a first end <NUM> of plunger lever <NUM> and a second lever interference surface <NUM> of head <NUM>, force pin <NUM>, second end <NUM> of plunger rod <NUM>, and first lever surface <NUM> away from first lever interference surface <NUM> of head <NUM>. The translation of plunger rod <NUM> away from axis A-A' causes first end <NUM> of plunger rod <NUM> to translate out of plunger opening <NUM>. The translation of plunger rod <NUM> away from axis A-A' also compresses compression spring <NUM> between spring interference surface <NUM> and bushing <NUM>.

With reference to <FIG>, a cross-section view of first restraint <NUM>, taken along line <NUM>-<NUM> in <FIG>, is illustrated, with plunger <NUM> in the disengaged state and first restraint <NUM> beginning to translate toward the stowed position. In response to first end <NUM> of plunger rod <NUM> being located outside of plunger opening <NUM>, head <NUM> can rotate about shroud <NUM>. Stated differently, locating first end <NUM> of plunger rod <NUM> radially outward of outer circumferential surface <NUM> removes the interference between shroud <NUM> and plunger rod <NUM>, thereby allowing first end <NUM> of plunger rod <NUM> to translate circumferentially about axis A-A' and along the outer circumferential surface <NUM> of shroud <NUM>. Shroud <NUM> does not rotate due to the contact between notch <NUM> and first outer tube <NUM>. With plunger <NUM> in the disengaged state, head <NUM> can be rotated in a second circumferential direction about shroud <NUM>, first outer tube <NUM>, and axis A-A' (e.g., toward the stowed position) in response to a load L3 greater than the biasing force of head torsion spring <NUM> being applied to head <NUM>.

As head <NUM> is rotated in the second circumferential direction, outer circumferential surface <NUM> blocks first end <NUM> of plunger rod <NUM> from translating radially inward (i.e., toward axis A-A'), thereby maintaining the distance between pin <NUM> and first lever interference surface <NUM> of head <NUM> and between second end <NUM> of plunger rod <NUM> and first lever interference surface <NUM>. The increased distance from first lever interference surface <NUM>, along with the biasing force applied by plunger torsion spring <NUM>, forces plunger lever <NUM> to rotate in the first circumferential direction about pin <NUM>. Plunger lever <NUM> may rotate until first lever surface <NUM> contacts head <NUM> (e.g., until plunger lever <NUM> contacts first lever interference surface <NUM>). In the disengaged state, first end <NUM> of plunger lever <NUM> may be located above upper surface <NUM> of head <NUM>. Stated differently, a distance between first end <NUM> of plunger lever <NUM> and axis A-A' may be greater than the distance between upper surface <NUM> of head <NUM> and axis A-A', when plunger <NUM> is in the disengaged state.

With reference to <FIG> and <FIG>, as head <NUM> is rotated toward panel <NUM>, contact is generated between a vertical surface <NUM> of panel <NUM> and plunger lever <NUM>. Vertical surface <NUM> may be approximately perpendicular to upper surface <NUM> of panel <NUM> (<FIG>). As used in the previous context only, "approximately" means ± <NUM>° from perpendicular. The contact between vertical surface <NUM> and plunger lever <NUM> overcomes the biasing force applied by plunger torsion spring <NUM>, thereby forcing plunger lever <NUM> to rotate about pin <NUM> in the second circumferential direction about <NUM> (i.e., in a direction opposite the direction of the biasing load applied by plunger torsion spring <NUM>). Stated differently, the contact between vertical surface <NUM> and plunger lever <NUM> translates first end <NUM> of plunger lever <NUM> toward second lever interference surface <NUM>, thereby decreasing the distance between first end <NUM> of plunger lever <NUM> and axis A-A'.

With reference to <FIG>, a cross-section view of first restraint <NUM>, taken along line <NUM>-<NUM> in <FIG>, is illustrated, with plunger <NUM> in the disengaged state and first restraint <NUM> in the stowed position. In response to first end <NUM> of plunger lever <NUM> translating past the edge of vertical surface <NUM>, plunger torsion spring <NUM> forces plunger lever <NUM> toward rotate in the first circumferential direction about pin <NUM>, thereby forcing first end <NUM> to translate past (e.g., above) upper surface <NUM> of head <NUM>. Load L3 (<FIG>) may be removed from, and/or no longer applied to, head <NUM> in response to first end <NUM> of plunger lever <NUM> translating past the edge of vertical surface <NUM>. In response to the load L3 being removed from head <NUM>, head torsion spring <NUM> may bias head <NUM> in the first circumferential direction about axis A-A'. The biasing force of head torsion spring <NUM> forces first end <NUM> of plunger lever <NUM> toward a lower surface <NUM> of panel <NUM>. Lower surface <NUM> of panel is oriented away from upper surface <NUM> of panel. The contact between first end <NUM> of plunger lever <NUM> and lower surface <NUM> of panel <NUM> maintains head <NUM> in the stowed position. Stated differently, the interference between plunger lever <NUM> and lower surface <NUM> prevents first restraint <NUM> from translating to the raised position.

With reference to <FIG>, a cross-section view of second restraint 102b, taken along line <NUM>-<NUM> in <FIG>, is illustrated, with the plunger in the disengaged state and prior to second restraint 102b being translated from the stowed state toward the raised state. second restraint 102b is substantially similar to first restraint 102a, though second restraint 102b is actuated by second outer tube <NUM>. In accordance with various embodiments, to translate second restraint 102b from the stowed position to the raised position, plunger <NUM> is translated to the engaged position, thereby rotationally coupling head <NUM> to shroud <NUM> and first outer tube <NUM>. In this regard, second outer tube <NUM> is rotated about axis A-A', thereby causing shroud <NUM> to rotate about axis A-A'. The rotation of shroud <NUM> brings protrusion <NUM> of shroud <NUM> into contact with drive cap <NUM>. Protrusion <NUM> and drive cap <NUM> are configured such that plunger opening <NUM> is radially aligned with the first end <NUM> of plunger rod <NUM> when protrusion <NUM> contacts drive cap <NUM>, however, the frictional force between lower surface <NUM> and plunger lever <NUM> be prevent plunger rod <NUM> from translating into plunger opening <NUM>. In this regard, the contact between protrusion <NUM> and drive cap <NUM> may force head <NUM> to rotate in the second circumferential direction about axis A-A' (i.e., away from the raised position and in the direction opposite the direction of the biasing load applied by head torsion spring <NUM>). The rotation of head <NUM> in the second circumferential direction about axis A-A' forces first end <NUM> of plunger lever <NUM> away from lower surface <NUM> of panel <NUM>.

With additional reference to <FIG>, inner shaft <NUM> drives rotation of second outer tube <NUM>. In that regard, inner shaft actuator assembly <NUM> may be used to rotate inner shaft <NUM> to cause actuation of second restrain 102b.

With reference to <FIG>, coaxial actuator assembly <NUM> is illustrated, in accordance with various embodiments is illustrated. Coaxial actuator assembly <NUM> may couple with drive shaft assembly <NUM>, wherein the first outer tube <NUM> and the inner shaft <NUM> are disposed coaxially about the A-A' axis. Coaxial actuator assembly <NUM> comprises inner shaft actuator assembly <NUM> and first outer tube actuator assembly <NUM>. First outer tube actuator assembly <NUM> includes a first spring loaded plunger lever <NUM>. Additionally, coaxial actuator assembly <NUM> includes inner shaft actuator assembly <NUM> coupled to the drive shaft assembly <NUM>. Second spring loaded plunger lever <NUM> may be coupled to the inner shaft actuator assembly <NUM>.

First outer tube actuator assembly <NUM> further includes a first geometric gripping surface <NUM>. Inner shaft actuator assembly <NUM> includes a second geometric gripping surface <NUM>. A tool may be used to grip on and rotate the first geometric gripping surface <NUM> or the second geometric gripping surface <NUM>. The tool may be a wrench, channel lock pliers, pliers or any other suitable tool which can grip on to a geometric surface and impart rotation around the axis. The tool may also be a motorized system, such as an electromechanical actuator and/or electric motor such as a brushless DC motor, which may receive a command to rotate the first geometric gripping surface <NUM> or second geometric gripping surface <NUM> in response to a rotational command by a controller. The rotational command may be transmitted by the controller to the motorized system in response to a switch being activated.

With reference to <FIG> and <FIG>, a cross-section view of first outer tube actuator assembly <NUM> of the coaxial actuator assembly <NUM> in <FIG> is illustrated. The first outer tube actuator assembly <NUM> may comprise a first actuator tube <NUM> disposed within the first outer tube actuator assembly <NUM>. The first actuator tube <NUM> is coupled to the first outer tube <NUM> at a first notch <NUM> and a second notch <NUM>. The first notch <NUM> and the second notch <NUM> may be extensions of the first outer tube <NUM> which are configured to rotate the first outer tube <NUM> in response to rotation of the first actuator tube <NUM>. The first notch <NUM> and the second notch <NUM> may be disposed on opposite sides of the first outer tube <NUM>. Rotation of the first actuator tube <NUM> about axis A-A' causes first outer tube <NUM> to rotate in the same direction about axis A-A' as first actuator tube <NUM> due to the contact between first notch <NUM> and first actuator tube <NUM> and the contact between second notch <NUM> and first actuator tube <NUM>.

A first spring loaded plunger <NUM> is disposed within the first outer tube actuator assembly <NUM>, and the first spring loaded plunger <NUM> includes a first spring loaded plunger rod <NUM> and the first spring loaded plunger lever <NUM>. First spring loaded plunger rod <NUM> is configured to translate radially (i.e., perpendicular to axis A-A'). In this regard, first spring loaded plunger rod <NUM> translates toward and away from first outer tube <NUM>. In various embodiments, first spring loaded plunger rod <NUM> may be located in a first spring loaded plunger channel <NUM>. A compression spring <NUM> may be located about first spring loaded plunger rod <NUM>. Compression spring <NUM> may be compressed between a first spring interference surface <NUM> and a second spring interference <NUM> formed by the first spring loaded plunger rod <NUM>. Compression spring <NUM> biases a first end of plunger rod in the radially inward direction (i.e., toward first outer tube <NUM> and axis A-A). Compression spring <NUM> comprises any suitable spring, such as a coil spring, leaf spring, Belleville spring, or the like.

A first actuator lever pin <NUM> may be located through first spring loaded plunger rod <NUM> and first spring loaded plunger lever <NUM>. First actuator lever pin <NUM> may be located proximate a second end of first spring loaded plunger rod <NUM>. The second end of first spring loaded plunger rod <NUM> is opposite the first end. First spring loaded plunger lever <NUM> may rotate about first actuator lever pin <NUM>. A first plunger torsion spring may be located about first actuator lever pin <NUM> and may apply a biasing load to first spring loaded plunger lever <NUM>. First plunger torsion spring may bias first spring loaded plunger lever <NUM> in the first circumferential direction about first actuator lever pin <NUM>.

The first actuator tube <NUM> also comprises a first actuator tube opening <NUM> and a second actuator tube opening <NUM>. The first spring loaded plunger <NUM> is configured to fit into the first actuator tube opening <NUM> and the second actuator tube opening <NUM>. When the first spring loaded plunger <NUM> is in the first actuator tube opening <NUM> or the second actuator tube opening <NUM>, then the first actuator tube <NUM> and the first outer tube <NUM> are prevented from rotating about the A-A' axis. In response to a force exerted on the first spring loaded plunger lever <NUM> in the direction towards the drive shaft assembly <NUM>, the first spring loaded plunger rod <NUM> translates in the direction opposite the first outer tube <NUM> and perpendicular to the A-A' axis. This allows both the first actuator tube <NUM> and the first outer tube <NUM> to rotate about the A-A' axis. The first outer tube <NUM> and the first actuator tube <NUM> coaxially rotate about the A-A' axis in response to the first spring loaded plunger lever <NUM> translating the first spring loaded plunger <NUM> out of the first actuator tube opening <NUM> or the second actuator tube opening <NUM>, and in response to the first geometric gripping surface <NUM> driving rotation of the first outer tube <NUM>.

With reference to <FIG> and <FIG>, a cross-section view of the comprises inner shaft actuator assembly <NUM> of the coaxial actuator assembly <NUM> in <FIG> is illustrated. The inner shaft actuator assembly <NUM> comprises a second actuator tube <NUM>. Second actuator tube <NUM> is coupled to the inner shaft <NUM> at a first notch <NUM> and a second notch <NUM>. The first notch <NUM> and the second notch <NUM> may be extensions of the inner shaft <NUM> which are configured to rotate the inner shaft <NUM> in response to rotation of the second actuator tube <NUM>. The first notch <NUM> and the second notch <NUM> may be disposed on opposite sides of the inner shaft <NUM>. Rotation of the second actuator tube <NUM> about axis A-A' causes inner shaft <NUM> to rotate in the same direction about axis A-A' second actuator tube <NUM> due to the contact between first notch <NUM> and second actuator tube <NUM> and the contact between second notch <NUM> and second actuator tube <NUM>.

A first spring loaded plunger <NUM> is disposed within inner shaft actuator assembly <NUM>, and the first spring loaded plunger <NUM> includes a second spring loaded plunger rod <NUM> and the second spring loaded plunger lever <NUM>. Second spring loaded plunger rod <NUM> is configured to translate radially (i.e., perpendicular to axis A-A'). In this regard, second spring loaded plunger rod <NUM> translates toward and away from inner shaft <NUM>. In various embodiments, second spring loaded plunger rod <NUM> may be located in a second spring loaded plunger channel <NUM>. Compression spring <NUM> may be located about second spring loaded plunger rod <NUM>. Compression spring <NUM> may be compressed between first spring interference surface <NUM> and a second spring interference <NUM> formed by the second spring loaded plunger rod <NUM>. Compression spring <NUM> biases a first end of second spring loaded plunger rod <NUM> in the radially inward direction (i.e., toward inner shaft <NUM> and axis A-A). Compression spring <NUM> comprises any suitable spring, such as a coil spring, leaf spring, Belleville spring, or the like.

A first actuator lever pin <NUM> may be located through second spring loaded plunger rod <NUM> and second spring loaded plunger lever <NUM>. First actuator lever pin <NUM> may be located proximate a second end of second spring loaded plunger rod <NUM>. The second end of second spring loaded plunger rod <NUM> is opposite the first end. Second spring loaded plunger lever <NUM> may rotate about first actuator lever pin <NUM>. A first plunger torsion spring may be located about first actuator lever pin <NUM> and may apply a biasing load to second spring loaded plunger lever <NUM>. First plunger torsion spring may bias first spring loaded plunger lever <NUM> second spring loaded plunger lever <NUM> in the first circumferential direction about first actuator lever pin <NUM>.

Second actuator tube <NUM> also comprises a first actuator tube opening <NUM> and a second actuator tube opening <NUM>. The spring loaded plunger <NUM> is configured to fit into the first actuator tube opening <NUM> and the second actuator tube opening <NUM>. When the spring loaded plunger <NUM> is in the first actuator tube opening <NUM> or the second actuator tube opening <NUM>, then the second actuator tube <NUM> and the inner shaft <NUM> are prevented from rotating about the A-A' axis. In response to a force exerted in the direction towards the drive shaft assembly <NUM> to the second spring loaded plunger lever <NUM>, then the second spring loaded plunger rod <NUM> translates in the direction opposite the inner shaft <NUM> and perpendicular to the A-A' axis and allows both the first actuator tube <NUM> and the first outer tube <NUM> to rotate about the A-A' axis. The inner shaft <NUM> and the second actuator tube <NUM> rotate about the A-A' axis in response to the second spring loaded plunger lever <NUM> translating the second spring loaded plunger rod <NUM> out the first actuator tube opening <NUM> or the second actuator tube opening <NUM>, and in response to the second geometric gripping surface <NUM> driving rotation of the inner shaft <NUM>.

Systems, methods, and apparatus are provided herein. In the detailed description herein, references to "one embodiment", "an embodiment", "an example embodiment", etc., indicate that the embodiment described may include a particular feature, structure, or characteristic, but every embodiment may not necessarily include the particular feature, structure, or characteristic.

Claim 1:
A restraint assembly actuation system for use with a cargo restraint system, comprising:
a drive shaft assembly (<NUM>) comprising a first outer tube (<NUM>) and an inner shaft (<NUM>), wherein the first outer tube and the inner shaft are disposed coaxially about an axis; and
a first restraint (102a) coupled to the first outer tube, wherein the first outer tube is configured to rotate the first restraint about the axis to a raised position to restrain a cargo load, wherein the first restraint comprises a head (<NUM>) configured to engage with the cargo load and characterised in that the first restraint comprises a shroud (<NUM>) coupled to the outside of the first outer tube, and a plunger rod (<NUM>) coupled to the shroud and the head.