Patent Description:
According to its abstract, <CIT> discloses a quadrotor unmanned aerial vehicle. The quadrotor unmanned aerial vehicle comprises a rotor mechanism, a central control shell, a fixing ring, a servo motor, a second rotary cylinder, a spring, an adjusting rod, and a guiding key; swing frames can swing in up and down movement of adjusting rings, and in the process of the swing frames swinging to the horizontal state, the spring does not participate in mechanical transmission, that is, the spring is not continued to stretch, the swing angle of the swing frames is proportional to the number of rotating turns of the servo motor, and thus the swing frames can be faster to achieve the smooth flight state.

According to its abstract, <CIT> provides a but folding frame, include: main frame, horn, support link and limiting locking mechanism, the horn with the main frame rotates to be connected, support link's both ends respectively with the horn with limiting locking mechanism rotates the connection, limiting locking mechanism sets up on the main frame, be used for driving the support link motion, thus realize opening with folding of horn, and can make the horn remains stable with fold condition opening.

According to its abstract, <CIT> provides a kind of collapsible frame, comprise: main frame, horn, support link and limitation locking mechanism, described horn and described main frame are rotationally connected, and the two ends of described support link are rotationally connected with described horn and described limitation locking mechanism respectively.

The present disclosure provides a deployment mechanism for arms of a drone. This mechanism is particularly of relevance to a drone that is housed in a container and is configured to be launched therefrom, and therefore is required to have an efficient deployment mechanism for its arms to be deployed immediately after the launch. The deployment mechanism is biased to its deployed state and is retained in its non-deployed state by external forces, such as the normal forces that are applied by the walls of the container on the arms while the drone is housed within the container. After the launch from the container, the above-mentioned forces are no longer applied to the arms of the drone and the deployment mechanism, causing a transition of the arms from their non-deployed state to their deployed state, in which they are in a position suitable for flying, i.e. activation of the rotors mounted on the arms.

The deployment mechanism comprises a biasing assembly that includes a biasing element, typically a spring, that prior to the launch is in its first, non-biased state, namely tensioned, and thus causing a biasing force of the biasing assembly against the arms. The biasing force may be applied on the arms by other elements/members of the biasing assembly that are displaceable with the biasing element. Thus, the biasing element causes members/elements of the biasing assembly to displace therewith, and interfacing elements of the biasing assembly interface with the arms and urge them into their deployed state while there is no balancing force such as the normal forces applied by the walls of the container prior to the launch of the drone therefrom. During the displacement of the biasing element, it is transitioned from its first state to its second, biased, state that is defined at the end of the range of its displacement from the initial first state. During the transition, the biasing element constantly applies force that causes the biasing assembly to displace. It is to be noted that the biasing element, also in its biased state, may still be tensioned to some degree, which applies some biasing force, but less than the non-biased state. When the arms reach the deployed sate, the biasing assembly is configured to lock the arms in this position and maintain them deployed, e.g. by applying a locking force on a portion of the arms.

Thus, the present disclosure provides a drone according to appended claim <NUM>.

The first state is characterized by being less biased than the second state, namely the biasing force that is applied by the biasing element in the first state is greater than the second state, thus the first state is defined throughout the application as a non-biased state and the second state is defined throughout the application as a biased state. The drone and its biasing assembly are configured such that (i) during the displacement of the at least one interfacing element, namely while transitioning between the non-biased state to the biased state, , each interfacing element is configured to engage the proximal end portion of each respective arm so as to apply a biasing force sufficient to cause the transition of the arm between the non-deployed state and the deployed state, namely said pivotal transition and (ii) when the biasing assembly is in the biased state, each interfacing element restricts the pivotal movement of the arm and restrains it in the deployed state. It is to be noted, as mentioned above, that the non-biased state is defined along a range of positions of the biasing assembly. These positions are typically defined by a range of continuous angular positions about the pivoting element. The interfacing element interfaces with a portion of the arm at least at some of this range, but not necessarily the entire range. Namely, in some range of positions of the non-biased state of the biasing assembly the interfacing element may not interface with the arm, e.g. at an extreme position of the non-biased state, and after a certain extent of movement of the biasing assembly, the interfacing element interfaces with the arm and begins to cause its movement.

It is to be noted that any combination of the described embodiments with respect to any aspect of this present disclosure is applicable. In other words, any aspect of the present disclosure can be defined by any combination of the described embodiments, as far as said aspect falls within the scope of the appended claims.

In some embodiments of the drone, each arm has its own respective interfacing element. Namely, the drone comprises equal number of interfacing elements and arms.

In some embodiments of the drone, the two or more arms are generally axial-symmetric, namely each arm behaves similar to the other arms with respect to the central axis, though each in a different radial direction with respect to the central axis.

In some embodiments of the drone, the interfacing element is a bearing that bears on an integral lever portion of the arm. The lever portion is a part of the proximal portion of the arm.

In some embodiments of the drone, the arm is pivoted to the body by a pivot in between a main arm portion and the lever portion.

In some embodiments of the drone, the lever portion has an interfacing rim portion, and the interfacing element interfaces with said rim portion during said transition.

In some embodiments of the drone, each of the interfacing elements slides on said interfacing rim portion during said transition.

In some embodiments of the drone, the rim portion is substantially planar.

In some embodiments of the drone, the rim portion comprises a planar segment and a curved segment, wherein during the displacement of the biasing element from the non-biased state to the biased state, the bearing slides on both planar and curved segments.

In some embodiments of the drone, in the non-biased state, the rim portion is located axially to the interfacing element, namely along the central axis direction, below the interfacing element, where the upward direction is defined as the direction towards the body; and in the biased state, the rim portion located radially to the interfacing element, namely the interfacing element is disposed in the biased state along the radial axis between the lever portion and the biasing element/the displaceable member.

In some embodiments of the drone, the lever portion comprises a hollowed portion for reducing weight of the arm, while maintaining its dimensions and shape for allowing the interfacing element to apply the desired torque.

In some embodiments of the drone, in the non-biased state, the hollowed portion is located axially to the rim portion, and in the biased state the hollowed portion located radially to the rim portion.

In some embodiments of the drone, the lever portion is generally angled with respect to the main arm portion.

In some embodiments of the drone, the biasing element is a spring.

In some embodiments of the drone, the transition between the biased state and a non-biased state causes the simultaneous transition between the non-deployed state and the deployed state.

According to the presently claimed invention, the biasing assembly comprises an axially displaceable member that is biased, by the biasing element, to displace between a retracted state to an extended state. The displaceable member is coupled to the interfacing element and causes displacement of the interfacing element between respective non-biased and biased states.

In some embodiments of the drone, the displaceable member is an annular piston displaceable along a central shaft that guides displacement of said member. The biasing element is a helical spring fitted around said shaft and received in a spring seat within the piston.

In some embodiments of the drone, the displaceable member is displaced along a rigid guiding element.

In some embodiments of the drone, the displaceable member displaces along the central axis.

In some embodiments of the drone, the displaceable member comprises radial projections holding said interfacing element(s).

In some embodiments of the drone, the radial projections have tangential pins, and the interfacing element is a bearing mounted on said pins. The bearing may revolve about said pins.

According to the presently claimed invention, the biasing assembly is coupled to the body such that it is capable of moving on a plane defined normal to the central axis.

According to the presently claimed invention, the displaceable member is rotatable about at least two axes in said plane.

In some embodiments of the drone, said displaceable member comprise a lumen and the biasing assembly comprises a shaft being received within said lumen to allow the displacement of the displaceable member, wherein the transversal cross section of the lumen is larger than the transversal cross section of the shaft, allowing the displaceable said moving on said plane and the rotation about at least two axes in said plane. Namely, there is a gap between the shaft and the inner walls of the lumen that provide tolerance in the movement of the displaceable member. This is important to allow the displaceable member the required tolerance to firmly lock at least three arms of the drone.

In some embodiments of the drone, the at least one interfacing element is constituted by a projection, wherein the projection is coupled to or integrally formed with the displaceable member.

In some embodiments of the drone, the projections are the interfacing elements are configured to engage with an integral lever portion of the arm.

In some embodiments of the drone, said projection projects normal to the central axis.

In some embodiments of the drone, said projection is fitted with an adjustable extension for adjusting the effective length of the projection. The adjustable extension is provided to compensate inaccuracies in the manufacturing process, allowing to adjust the effective lengths of the projections, i.e. the interfacing elements, to ensure that the locking of the arms is sufficient and not allowing any movement thereof.

In some embodiments of the drone, the adjustable extension is a screwing element fitted within a screwing space of the projection, e.g. an internal thread formed within a lumen of the projection.

In some embodiments of the drone, each arm comprises a limiting edge formed at the proximal end to limit the axial displacement of the biasing assembly and in particular to limit the axial displacement of the displacement member.

In some embodiments of the drone, the limiting edge is configured to engage one or more of the at least one interfacing element while the arms are in the deployed state, therefore, restricting the movement of the biasing assembly.

In some embodiments of the drone, when the biasing assembly is in the non-biased state the proximal portion of each arm is located between each of the respective at least one interfacing element and the rotor along axes defined parallel to the central axis such that a displacement directionality along the central axis of the at least one interfacing element causes the engagement of it with the proximal portion of the arm. Namely, the order of the elements of the drone in the non-biased state along such axes is: the drone's body, the interfacing elements, the proximal portion of the arm, the distal portion of the arm with the rotor on its edge.

Another aspect of the present disclosure provides a container that includes the drone of any one of the above-described embodiments.

In some embodiments of the container, the drone is housed within the container with its arms in a non-deployed state.

An example not covered by the presently claimed invention provides a method for deploying arms of a drone following its launch from a container. The example drone comprises a body defining central axis and each arm (i) comprises a rotor disposed at a distal end portion, and (ii) being pivotally coupled to the body at a proximal end portion to allow a pivotal transition between a first, non-deployed state in which the arms extend substantially in the axial direction, and a second, deployed state in which the arms extend from the body substantially in the radial direction. The method comprising applying a single biasing force causing simultaneous transition of all the arms between the non-deployed state to the deployed state. The biasing force is constantly applied during the housing of the drone in the container and the arms retained in their non-deployed state due to a balancing force applied by the walls of the container. Once the drone is launched from the container, the single biasing force causes the four arms to simultaneously transition to the deployed state.

With respect to the example method, the biasing force results in displacement of interfacing elements, each interfaces a respective proximal end portion and causing said transition.

With respect to the example method, the method further comprising locking the arms in their deployed state. The locking is performed by a geometrical locking, thus not allowing the arms to return to their non-deployed state.

With respect to the example method, the drone is any one of the above-described embodiments relating to the drone aspect.

The following figures are provided to exemplify embodiments and realization of the invention of the present disclosure.

Reference is first being made to <FIG>, which are illustrations of a non-limiting example of an embodiment of the drone and/or its deployment and locking mechanism according to an aspect of the present disclosure. <FIG><FIG>show the drone in its non-deployed state, <FIG>, <FIG>show the drone in its deployed state and <FIG> show the drone during transition between the non-deployed state and the deployed state.

The drone <NUM> includes a body <NUM> defining a central axis CA along the longitude of the drone <NUM>. The drone <NUM> further includes arms <NUM> each pivotally coupled to the body <NUM> at its proximal end portion <NUM> and is having a rotor <NUM> on its distal end portion <NUM>. The proximal end portion is defined by the half portion of the arm that is proximal to the body and the distal portion is defined by the half portion of the arm that is distal from the body. The arms are pivoted to the body by a pivoting element <NUM> to allow a pivotal movement of the arm for transition from a non-deployed state to a deployed state of the arms. In the non-deployed state, the arms are generally extending parallel to the central axis CA and in the deployed state, the arms are extending radially with respect to the central axis CA.

A biasing assembly <NUM> of the drone <NUM> includes a biasing element <NUM> in the form of a spring that is capable of transitioning between a non-biased state, i.e. a state where the spring is tensioned, and a non-biased state, i.e. a state where the spring is released. The biasing assembly <NUM> further includes a displaceable member <NUM> and interfacing elements <NUM> integral with the displaceable member <NUM>, both movable with the biasing element, each interfacing element <NUM> interfaces with a respective arm <NUM>. Each interfacing element <NUM> is held by a pin <NUM> formed on a respective projection <NUM> that is radially projecting from the displaceable member <NUM>, the pin is oriented tangentially with respect to the radial direction defined by the arms <NUM>. The movement of the biasing element <NUM>, the displaceable member <NUM> and the interfacing elements <NUM> resulting in the transition of the arms from the non-deployed state to the deployed state by application of force of the interfacing elements <NUM> on a lever portion <NUM> of the arms <NUM>. While the drone is housed within a drone container <NUM>, e.g. prior to its launch therefrom, the walls <NUM> of container <NUM> apply a balancing torque to the torque applied by the interfacing elements <NUM> on the arms <NUM>, as can be seen in <FIG>, and the arms <NUM> retain in their non-deployed state. Once the drone <NUM> is ejected from the container <NUM>, the biasing element <NUM> is displaced to its biased state, namely to its released, non-tensioned state, and each interfacing element <NUM> urges against the respective lever portion <NUM> and causes the arm <NUM> to pivot from the non-deployed state to the deployed state, as can be seen in <FIG>.

The displaceable member <NUM> axially displaces along an axial guiding element <NUM> that extends along the central axis CA. The biasing element <NUM> is accommodated within a volume confined by the displaceable member <NUM>, and displacement of the biasing element <NUM> causes a corresponding displacement of the displaceable member <NUM> such that the displacement of the two is simultaneous.

Each interfacing element <NUM> engages an interface rim portion <NUM> at the lever portion <NUM> of the arm <NUM>. The rim portion is a part of the peripheral rim defining the arm. In the non-deployed state, the interface rim portion <NUM> and the interfacing elements <NUM> are axially aligned with respect to one another, as can be best seen in <FIG>, and in the deployed state, the interface rim portion <NUM> and the interfacing elements <NUM> are radially aligned with respect to one another, as can be best seen in <FIG>. The interface rim portion <NUM> that is part of the arms of the drone includes a first section <NUM> and a second, planar, section <NUM>. The interfacing elements <NUM> engage the first and the second sections <NUM> and <NUM> intermittently during the transition from the non-deployed state to the deployed state. <FIG> shows the engagement pattern of the engaging elements <NUM> of the biasing assembly <NUM> with the interface rim portion <NUM>, namely with the first and the second sections <NUM> and <NUM> during the transition from the non-deployed state to the deployed state. At the beginning of the transition, as shown in <FIG>, the engaging elements <NUM> engage the second section <NUM> at a most distal position to the first section <NUM>. <FIG> shows a more progressed phase of the transition, in which the engaging elements <NUM> still engage the second section <NUM> and getting more proximal to the first section <NUM>. In <FIG> it is shown that the engaging elements <NUM> engage the first section <NUM>, and at the end of the transitioning, as shown in <FIG>, the engaging elements <NUM> engage again the second section <NUM> to provide a geometrical lock. The interface rim portion <NUM> includes a geometrical discontinuity profile in the transition between the first and the second sections, resulting in a disengagement between the engaging elements <NUM> and the interface rim portion <NUM> when the engagement of the engaging elements <NUM> transitioning between the first and the section sections <NUM> and <NUM> and vice versa. It is to be noted that the engagement with the first section <NUM> can be only with the transition portion between the first and second sections <NUM> and <NUM>, namely with the geometrical discontinuity profile. The first section <NUM> may be curved or planar that defines a plane angled to the plane defined by the second, planar, section <NUM>. This structure ensures that the transition is carried out completely and does not stop in an intermediate position. At the end of the transition, the biasing element reaches its most extended range and this results in that the interfacing elements <NUM> engaging the second, planar, section <NUM> such that the force that may be applied on the interfacing element by the arms cannot result in the compression of the biasing element and any force applied by the interfacing element on the arm cannot result in a torque that causes the transition of the arm back to the folded state, thereby causing a geometrical locking. In order to permit the reverse transition of the arms back to the folded state, an axial force on the biasing element needs to be applied in the direction causing the compression of the biasing element, followed by application of torque on the arms that causes the arms to pivot into the folded state. Each arm <NUM> is formed by a proximal segment <NUM> that comprises the lever portion <NUM> and a distal segment <NUM> on which the rotor <NUM> is mounted. The proximal segment <NUM> is coupled to the body <NUM> via the pivoting element <NUM> at the lever portion <NUM> and is coupled to the distal segment <NUM> at an opposite side. The proximal segment <NUM> is constituted by the lever portion <NUM> and an elongated part <NUM>. The lever portion <NUM> projects from the elongated part <NUM> and thus angled thereto. <FIG> are different exploded views of the drone in its deployed state, not showing the distal segment. As can be seen in these figures, the proximal segment <NUM> includes a receiving arrangement <NUM> for receiving the distal segment <NUM>.

Furthermore, the lever portion <NUM> of each arm includes a hollowed portion <NUM> for reducing the weight of the arm while maintaining its peripheral dimensions, namely its contour.

<FIG> are schematic illustrations of cross-sectional views of another embodiment of a non-limiting example of the biasing assembly and the arms of the drone of the present disclosure. In this example, the interfacing elements <NUM> are in the form of projections projecting normal to the central axis. In the non-biased state, as shown in <FIG>, the interfacing elements <NUM> are not in contact with the proximal end portions <NUM> of the arms. The proximal end portions <NUM> of the arms are located in the displacement path of the interfacing elements <NUM> such that during the displacement of the displaceable member <NUM> the projections engages with the proximal end portions <NUM> of the arms, or in particular a lever portion <NUM> in the proximal end portion of each arm, and applying on them force causing the transition between a first, non-deployed state in which the arms extend substantially in the axial direction, and a second, deployed state in which the arms extend from the body substantially in the radial direction (<FIG> shows the transition state and <FIG> shows the deployed state of the arms).

The interfacing <NUM> elements comprises adjustable extensions <NUM> configured to allow to effectively extend the length of the interfacing element along an axis normal to the central axis. The extensions may then be adjusted separately for each arm, preventing an incomplete transition to the deployed state where one or more arms does not contact the interfacing element due to manufacturing tolerances or other factors. In this non-limiting example the adjustable extensions are in the form of screws that fit within an internal thread of the interfacing elements <NUM>, though it is to be noted that other solutions are optional as well.

Furthermore, in this example, the proximal end portions <NUM> of the arms comprises a limiting edge <NUM> that is configured to limit the displacement movement of the interfacing elements <NUM> and the displaceable member <NUM> at the end of the transition to the deployed state. The arms are restricted in movement beyond the <NUM>° rotation that they perform in the transition from the non-deployed state to the deployed state, and in the end of this transition the interfacing elements <NUM> may reach a stopping condition where they engage the limiting edge that protrudes, in the deployed state, in a direction normal to the central axis towards the displaceable member <NUM> such that a portion of each interfacing element <NUM> engages with the respective limiting edge <NUM> and is prevented to continue in the movement of the displacement caused by the biasing element. Alternatively, one or more interfacing elements <NUM> may contact its corresponding arm so that friction and reaction forces from the arm create a jamming condition that prevents the displaceable member from advancing to the point where the interfacing element <NUM> contacts the limiting edge <NUM>.

In the example shown in <FIG> and also in the example shown in <FIG>the displaceable member <NUM>/<NUM> mainly displaces along a shaft <NUM>/<NUM>. Namely, the displaceable member <NUM>/<NUM> comprises a lumen surrounding the shaft <NUM>/<NUM>. The shaft <NUM>/<NUM> according to examples not forming part of the presently claimed invention can be (i) tightly surrounded by the displaceable member <NUM>/<NUM> therefore the displacement of the displaceable member <NUM>/<NUM> is limited mainly along the central axis. However, according to the presently claimed invention, the shaft <NUM>/<NUM> is (ii) loosely surrounded by the displaceable member <NUM>/<NUM>, namely such that there is a gap between the shaft and the internal walls of the lumen, allowing the displaceable member <NUM>/<NUM> to have several degrees of freedom in its movement, e.g. displacement along the central axis, displacement on a plane defined normal to the central axis and/or rotation about two or more axes defined on said plane defined normal to the central axis.

Claim 1:
A drone (<NUM>) comprising:
a body (<NUM>) defining a central axis (CA);
two or more arms (<NUM>), each arm (<NUM>) (i) comprising a rotor (<NUM>) disposed at a distal end portion (<NUM>), and (ii) being pivotally coupled to the body (<NUM>) at a proximal end portion (<NUM>, <NUM>) to allow a pivotal transition between a first, non-deployed state in which the arms (<NUM>) extend substantially in a direction of the central axis (CA), and a second, deployed state in which the arms (<NUM>) extend from the body (<NUM>) substantially in a radial direction with respect to the central axis (CA);
a biasing assembly (<NUM>) that comprises (i) at least one biasing element, and (ii) at least one interfacing element (<NUM>, <NUM>) being configured to be displaced by the biasing element, between a non-biased state and a biased state; wherein
(i) during said displacement of the at least one interfacing element (<NUM>, <NUM>), each of the at least one interfacing elements (<NUM>, <NUM>) is configured to engage the proximal end portion (<NUM>, <NUM>) of each respective arm (<NUM>) so as to apply a biasing force sufficient to cause said pivotal transition, and wherein (ii) when the biasing assembly (<NUM>) is in the biased state, each interfacing element (<NUM>, <NUM>) restricts the pivotal transition of the arm (<NUM>) and restrains it in the deployed state;
wherein the biasing assembly (<NUM>) comprises an axially displaceable member (<NUM>, <NUM>) that is biased, by the biasing element, to displace between a retracted state and an extended state, said axially displaceable member (<NUM>, <NUM>) being coupled to or integral with the interfacing element (<NUM>, <NUM>), whereby the axially displaceable member (<NUM>, <NUM>) causes displacement of the interfacing element (<NUM>, <NUM>) between respective non-biased and biased states;
characterized in that
the axially displaceable member (<NUM>, <NUM>) is capable of moving on a plane defined normal to the central axis (CA); and
in that the axially displaceable member (<NUM>, <NUM>) is rotatable about at least two axes in said plane.