EXTENDING AIRFRAME BEAM SPRING LOCK

Description

CLAIM OF PRIORITY

This patent application claims the benefit of priority to U.S. Provisional Application Serial No. 63/703,541, filed October 4, 2024, which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

Examples relate to an airframe for a projectile and more specifically to a locking mechanism that allows the projectile to have a retracted configuration and an expanded configuration.

BACKGROUND

A projectile is typically fired from a launching system with a propellant. In order to maximize a distance the projectile travels, the projectile needs to maximize the amount of propellant on board. In some instances, a portion of the propellant, such as liquid propellant, can be provided to the projectile from the launching system. Typically, the projectile is constrained by the dimensions of the launching system . More specifically, in order to be compatible with the launching system, the projectile cannot have dimensions that exceed those of the launching system. Therefore, the size constraints imposed by the launching system constrain the amount of propellant the projectile can have, which can impact a maximum distance the projectile can travel after launch.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates an environment in which examples may operate.

FIG. 2 illustrates a projectile in a retracted configuration.

FIG. 3 shows the projectile of FIG. 2 in an expanded configuration.

FIG. 4 illustrates a locking assembly of the projectile of FIG. 2.

FIG. 5 shows a groove of a piston of the projectile of FIG. 2.

FIG. 6 illustrates the locking assembly of FIG. 4 when the projectile is in an expanded configuration.

FIG. 7 details the locking assembly of FIG. 4 when the projectile is in an expanded configuration different from the expanded configuration of FIG. 6.

FIGS. 8A and 8B show a bottom spring of the projectile of FIG. 2.

FIG. 9 illustrates a cylinder of the projectile of FIG. 2.

FIGS. 10 and 11 show alternative examples of a cylinder and a piston that can be used with a projectile.

DETAILED DESCRIPTION

The following description and the drawings sufficiently illustrate teachings to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. Portions and features of some examples may be included in, or substituted for, those of other examples. Teachings set forth in the claims encompass all available equivalents of those claims.

Examples relate to a projectile that has a retracted configuration and expanded configurations. The projectile can include an airframe having a cylinder and a piston disposed within the cylinder. The piston can be movable with respect to the cylinder. The cylinder can include a locking assembly disposed at a distal end of the cylinder. The locking assembly can have a leaf spring that can bias the piston in a first expanded configuration. Moreover, the leaf spring can lock the cylinder in a second expanded configuration. A bottom spring can also be disposed at the cylinder distal end. The bottom spring can be configured to engage the piston when the piston is in each of the expanded configurations.

The piston can include a groove at a distal end of the piston. The groove can be configured to receive the leaf spring. The piston can move between the first expanded configuration and the second expanded configuration when a propellant, which can be a fluid, is provided to the piston. In the first expanded configuration, the fluid can be provided at a first pressure, which can cause the piston to move towards the cylinder distal end where the bottom spring can limit movement of the piston. The bottom spring can limit the movement of the piston such that the leaf spring can bias the piston distal end. Moreover, the leaf spring can be spaced apart from the piston groove and therefore be misaligned with the piston groove. When the piston is in the first expanded configuration, the fluid can be withdrawn from the piston such that the piston can move back to the retracted configuration.

In the second expanded configuration, the fluid can be provided to the piston at a second pressure greater than the first pressure. In the second expanded configuration, the piston groove can align with the leaf spring such that the piston groove can receive the leaf spring. When the piston groove receives the leaf spring, the projectile can be locked into the second configuration. Furthermore, when the piston groove receives the leaf spring, the piston can be rigidly fixed with respect to the cylinder.

Now referring to FIG. 1, a launching system 100 that can be used to launch a projectile 200 (FIGS. 2 and 3) is shown. The launching system 100 can be a mobile launching system or a fixed launching system. When the projectile 200 is loaded into the launching system 100, the launching system 100 can provide a propellent, such as a liquid fuel, to the projectile 200. The propellent can increase the distance that the projectile 200 can travel after launch from the launching system 100.

The projectile 200 can include an airframe comprising a cylinder 202, a piston 204 disposed within the cylinder 202, and a fuel area 206. The piston 204 can include a munitions section 208 in instances where the projectile is a missile. The fuel area 206 can include a solid fuel 210 for the projectile 200. The solid fuel 210 can include an oxidizer, a primary fuel, and a binder that holds the fuel and oxidizer together.

In FIG. 2, the projectile 200 is shown in a retracted configuration where the piston 204 is disposed within a housing 212 of the cylinder 202. The projectile 200 can be in the retracted position during transport and when the projectile 200 is disposed within the launching system 100 prior to launch. The piston 204 can slide relative to the cylinder 202 along directions X and Y. More specifically, the piston 204 is movable relative to the cylinder 202 and can slide within the cylinder housing 212 along the directions X and Y into first and second expanded configurations and into the retracted configuration shown with respect to FIG. 2.

The piston 204 can move relative to the cylinder 202 along the direction Y into the expanded configuration shown with reference to FIG. 3. As will be discussed further on, the projectile 200 can have a plurality of expanded configurations. In the expanded configuration of FIG. 3, the piston 204 can be locked relative to the cylinder 202 such that the projectile 200 can be launched from the launching system 100. In order to facilitate locking of the piston 204 relative to the cylinder 202, the projectile 200 can include a locking assembly 214 at a distal end 216 of the cylinder 202.

The locking assembly 214 can function to hold the projectile 200 in different expanded configurations. Now making reference to FIG. 4, the locking assembly 214 can define a housing 400 within which a leaf spring 402 can be disposed. The leaf spring 402 can be formed from spring steel that can be formed, annealed, rolled, and then heat treated. Examples of spring steel can include high carbon spring steels, alloy spring steels, and stainless spring steels. The leaf spring 402 can extend out of the locking assembly housing 400 though an opening 404. The leaf spring 402 can extend through locking assembly housing opening 404 as shown with reference to FIG. 4 when the leaf spring 402 locks the cylinder 202 with the piston 204, as will be discussed further on.

The locking assembly housing 400 can also include a post 406 at a proximal end 408 of the locking assembly housing 400. The leaf spring 402 can be wound about the post 406, thereby fixedly coupling the leaf spring 402 to the locking assembly housing 400. The locking assembly housing 400 can also include a spring limiter 410. The leaf spring 402 can be operatively coupled with the spring limiter 410 where the spring limiter 410 can be positioned at a sidewall 411 of the locking assembly housing 400 to adjust a spring rate of the leaf spring 402. To further illustrate, if the spring limiter 410 is moved closer to the locking assembly housing proximal end 408 and further away from a distal end 412 of the locking assembly housing 400, the spring rate of the leaf spring 402 can be lowered. If the spring limiter is moved closer to the locking assembly housing distal end 412 and further away from the locking assembly housing proximal end 408, the spring rate of the leaf spring 402 can be increased.

The locking assembly housing 400 can be formed with a metal stamping. Each of the post 406 and the spring limiter 410 can also be metal stamped within the locking assembly housing 400. The locking assembly housing 400 can also be formed through injection molding. Each of the post 406 and the spring limiter 410 can also be formed within the locking assembly housing 400 during injection molding of the locking assembly housing 400.

In addition to, or in conjunction with, adjusting a position of the post 406 within the locking assembly housing 400, a spring rate of the leaf spring 402 can be adjusted with a thickness 414 of the leaf spring 402. More specifically, the leaf spring thickness 414 can be adjusted, such as being increased, to minimize the possibility of buckling as the piston 204 provides a compressive force on the leaf spring 402 when the piston 204 is in an expanded configuration and locked with the cylinder 202. Increasing the leaf spring thickness 414 can also adjust the spring rate of the leaf spring 402. Moreover, the leaf spring thickness 414 can be decreased to adjust the spring rate of the leaf spring 402.

As mentioned above, the piston 204 can move between a retracted configuration within the cylinder 202 and multiple expanded configurations. In one expanded configuration, the piston 204 can be locked relative to the cylinder 202. In particular, the piston 204 can include a groove 500 at a distal end 502 of the piston 204. The piston groove 500 can be disposed around an entire periphery of the piston 500. Thus, if the cylinder 202 has multiple locking assemblies 214 each having leaf springs 402, the single piston groove 500 can be aligned with all of the leaf springs 402 and be configured to receive the leaf springs 402 in the locked position. The piston groove 500 can be configured to receive the leaf spring 402 when the piston 204 is in the expanded configuration where the piston 204 is locked relative to the cylinder 202, as shown with reference to FIG. 6.

When the launching system 100 provides a propellent, such as a fluid, into a piston housing 600, the propellent can be provided at a pressure suitable to move the piston 204 along the direction Y and into the expanded configuration shown with reference to FIG. 6. The pressure at which the propellant can be provided can be suitable to overcome a force imparted by a bottom spring 602 having spring elements 604 at the piston distal end 502, such as in a range of about 80 pounds per square inch (psi) to about 300 psi. In the expanded configuration of FIG. 6, the piston groove 500 can align with the leaf spring 402 such that the piston groove 500 can receive the leaf spring 402. When the piston groove 500 receives the leaf spring 402, the leaf spring 402 prevents movement of the piston 204 along the direction X. More specifically, the leaf spring 402 rests against a surface 606 of the piston groove 500, thereby preventing movement of the piston 204 along the direction X and locking the piston 204 in the expanded configuration shown with reference to FIG. 6.

In another expanded configuration, the piston 204 can move from the retracted configuration in FIG. 2 to the expanded configuration of FIG. 7. In the expanded configuration of FIG. 7, the piston 204 can move back into the retracted configuration of FIG. 2 from the expanded configuration of FIG. 7. More specifically, when the launching system 100 provides a propellent into the cylinder housing 600, the propellant can be provided to the cylinder housing 600 at a pressure that, while moving the piston 204 along the direction Y, cannot completely overcome a force imparted by the bottom spring 602. In particular, the pressure to achieve the configuration in FIG. 7 can be less than the pressure to achieve the configuration in FIG. 6. For example, the launch system 100 can provide the propellant in a range of about 8 psi to about 20 psi.

Since the force of the propellent provided by the launch system 100 does not completely overcome a force imparted by the bottom spring 602, the piston groove 500 does not align with the leaf spring 402 such that the piston groove 500 does not receive the leaf spring 402 in the example shown with reference to FIG. 7. Instead, the leaf spring 402 rests on a piston surface 504 and within a locking assembly housing window 416 where the piston groove 500 is misaligned with, and outside of, the leaf spring 402. A distal end 700 of the leaf spring 402 can be within the locking assembly housing window 416 in the expanded configuration of FIG. 7.

When the leaf spring 402 rests on the piston surface 504, the leaf spring 402 can bias the piston surface 504 along a direction Z, thereby minimizing movement of the piston 204. The leaf spring 402 is movable along the piston surface 504. As such, if the launch system 100 removes the propellant from the piston housing 600, the leaf spring 402 can move on the piston surface 504 along the direction Y as the piston 204 moves along the direction X such that the piston 204 can move into the retracted configuration shown with reference to FIG. 2 from the expanded configuration of FIG. 7. Thus, the piston 204 can move back and forth between the expanded configuration of FIG. 7 and the retracted configuration of FIG. 2.

As noted above, the bottom spring 602 can impart a force at the piston distal end 502 when the launch system 100 provides propellant into the piston housing 600. Now making reference to FIGS. 8A and 8B, the bottom spring 602 can have a configuration that can approximate the configuration of the cylinder 202. Thus, if the cylinder 202 has a circular configuration, the bottom spring 602 can have a circular configuration, as shown with reference to FIG. 8A. Furthermore, if the cylinder has a rectilinear configuration (FIG. 10), the bottom spring 602 can have a rectilinear configuration that can approximate the rectilinear configuration of the cylinder.

The spring elements 604 can resist compressive forces imparted by the piston distal end 502 when the piston 204 moves into the expanded configurations shown with reference to FIGS. 6 or FIG. 7. The spring elements can vary between a thickness 800 and a thickness 802, where the thickness 802 is less than the thickness 800. The thickness 800 can correlate to a thickness of the spring element 604 when the piston 204 is in a retracted configuration and the piston distal end 502 does not push against the bottom spring 602 and the spring elements 604. The thickness 802 can correlate to a thickness of the spring element 604 when the piston is in the expanded configuration of FIG. 7 and the piston distal end 502 pushes against the bottom spring 602 and the spring elements 604. The thickness 802 can also correlate to a thickness of the spring element 604 when the piston is in the expanded configuration of FIG. 6 and the piston distal end 502 pushes against the bottom spring 602 and the spring elements 604. The bottom spring 602 and the spring elements 604 can be formed of a metallic spring material similar to the materials used for the leaf spring 402 discussed above.

While only one locking assembly 214 is discussed above, the cylinder 202 can have a plurality of locking assemblies 214 each having the leaf spring 402. In particular, the cylinder 202 can have grooves 900 at a distal end 902 of the cylinder 202. The cylinder grooves 900 can have a plurality of locking assemblies 214. When the piston 204 is in an expanded configuration such that the piston groove 500 aligns with the plurality of the locking assemblies 214, the piston groove 500 can receive the plurality of leaf springs 402. In the example of the FIG. 9, the locking assemblies 214 can be symmetrically disposed about an inner surface 904 of the cylinder 202 at the cylinder distal end 902.

In addition to the circular configuration, each of the cylinder and the piston can have a rectilinear configuration, as shown with reference to FIGS. 10 and 11. A cylinder 1000 can have the cylinder grooves 900 at distal end 1002 of the cylinder 1000. Additionally, a piston 1100 can have a piston groove 1102 disposed about an entire outer surface of the piston such that the piston groove is configured to receive each of the plurality of leaf springs when the piston groove aligns with the plurality of leaf springs as the piston is in the second expanded configuration as described above. More specifically, when the piston 1100 is in an expanded configuration such that the piston groove 1102 aligns with the plurality of the locking assemblies 214 similar to the piston groove 500 described above, the piston groove 1102 can receive the plurality of leaf springs 402. In the example of the FIG. 10, the locking assemblies 214 can be disposed about an inner surface 1104 of the cylinder 1000 at the cylinder distal end 1102. Furthermore, the locking assemblies 214 can be disposed at a side 1106 of the cylinder 1000 at the cylinder distal end 1102.

Additional Examples

Example 1 is an airframe for a projectile comprising: a cylinder having: a locking assembly at a distal end of the cylinder, the locking assembly defining a housing, the locking assembly including: a leaf spring disposed within the locking assembly housing and fixedly coupled with a proximal end of the locking assembly housing; and limiter extending from a sidewall of the locking assembly housing, the leaf spring being operatively coupled with the limiter such that the limiter biases the leaf spring; a bottom spring at the cylinder distal end; and a piston disposed within the cylinder and moveable relative to the cylinder between a retracted configuration and first and second expanded configurations, the piston defining a housing, wherein the piston moves between each of the retracted configuration and the first and second expanded configurations when the piston housing receives a fluid, the piston including a groove configured to receive the leaf spring, the groove aligning with the leaf spring in the second expanded configuration where the piston groove receives the leaf spring in the second expanded configuration thereby locking the piston into the second expanded configuration and the leaf spring being outside of the piston groove in the first expanded configuration.

In Example 2, the subject matter of Example 1 includes, wherein the bottom spring biases the piston in the first expanded configuration such that the groove is misaligned with the leaf spring.

In Example 3, the subject matter of Example 2 includes, wherein the piston is configured to move to the retracted configuration from the first expanded configuration.

In Example 4, the subject matter of Examples 2–3 includes, wherein the leaf spring is configured to bias a surface of the piston when the piston is in the first expanded configuration.

In Example 5, the subject matter of Examples 1–4 includes, wherein the cylinder further includes a groove at the cylinder distal end and the locking assembly is disposed within the cylinder groove.

In Example 6, the subject matter of Example 5 includes, wherein: each of the cylinder and the piston have a circular configuration; and the cylinder includes a plurality of locking assemblies having a plurality of leaf springs, the plurality of locking assemblies being symmetrically disposed at the cylinder distal end, wherein the piston groove is disposed about an entire outer surface of the piston such that the piston groove is configured to receive each of the plurality of leaf springs when the piston groove aligns with the plurality of leaf springs as the piston is in the second expanded configuration.

In Example 7, the subject matter of Examples 5–6 includes, wherein: each of the cylinder and the piston have a rectilinear configuration; the cylinder includes a plurality of locking assemblies having a plurality of leaf springs, the plurality of locking assemblies being disposed at a side of the cylinder distal end, wherein the piston groove is disposed about an entire outer surface of the piston such that the piston groove is configured to receive each of the plurality of leaf springs when the piston groove aligns with the plurality of leaf springs as the piston is in the second expanded configuration.

In Example 8, the subject matter of Examples 1–7 includes, wherein the locking assembly housing has a post at the locking assembly proximal end and a portion of a proximal end of the leaf spring winds around the post thereby fixedly coupling the leaf spring to the locking assembly housing.

In Example 9, the subject matter of Examples 1–8 includes, wherein the locking assembly includes an opening at a distal end of the locking assembly, the locking assembly opening configured to a receive a proximal end of the leaf spring when the piston is in the first expanded configuration.

Example 10 is an airframe for a projectile comprising: a cylinder having: a locking assembly at a distal end of the cylinder, the locking assembly defining a housing, the locking assembly including: a leaf spring disposed within the locking assembly housing and fixedly coupled with a proximal end of the locking assembly housing; and limiter extending from a sidewall of the locking assembly housing, the leaf spring being operatively coupled with the limiter such that the limiter biases the leaf spring; a bottom spring at the cylinder distal end; and a piston disposed within the cylinder and moveable relative to the cylinder between a retracted configuration and first and second expanded configurations, the piston defining a housing, wherein the piston moves between each of the retracted configuration and the first and second expanded configurations when the piston housing receives a fluid, the piston including a groove configured to receive the leaf spring, the groove aligning with the leaf spring in the second expanded configuration where the piston groove receives the leaf spring in the second expanded configuration thereby locking the piston into the second expanded configuration and the leaf spring being outside of the piston groove in the first expanded configuration, wherein the bottom spring biases the piston in the first expanded configuration such that the groove is misaligned with the leaf spring.

In Example 11, the subject matter of Example 10 includes, wherein the piston is configured to move to the retracted configuration from the first expanded configuration and the leaf spring is configured to bias a surface of the piston when the piston is in the first expanded configuration.

In Example 12, the subject matter of Examples 10–11 includes, wherein the cylinder further includes a groove at the cylinder distal end and the locking assembly is disposed within the cylinder groove.

In Example 13, the subject matter of Example 12 includes, wherein: each of the cylinder and the piston have a circular configuration; and the cylinder includes a plurality of locking assemblies having a plurality of leaf springs, the plurality of locking assemblies being symmetrically disposed at the cylinder distal end, wherein the piston groove is disposed about an entire outer surface of the piston such that the piston groove is configured to receive each of the plurality of leaf springs when the piston groove aligns with the plurality of leaf springs as the piston is in the second expanded configuration.

In Example 14, the subject matter of Examples 12–13 includes, wherein: each of the cylinder and the piston have a rectilinear configuration; the cylinder includes a plurality of locking assemblies having a plurality of leaf springs, the plurality of locking assemblies being disposed at a side of the cylinder distal end, wherein the piston groove is disposed about an entire outer surface of the piston such that the piston groove is configured to receive each of the plurality of leaf springs when the piston groove aligns with the plurality of leaf springs as the piston is in the second expanded configuration.

In Example 15, the subject matter of Examples 10–14 includes, wherein the locking assembly housing has a post at the locking assembly proximal end and a portion of a proximal end of the leaf spring winds around the post thereby fixedly coupling the leaf spring to the locking assembly housing.

In Example 16, the subject matter of Examples 10–15 includes, wherein the locking assembly includes an opening at a distal end of the locking assembly, the locking assembly opening configured to a receive a proximal end of the leaf spring when the piston is in the first expanded configuration.

Example 17 is a locking assembly defining a housing, the locking assembly comprising: a leaf spring disposed within the locking assembly housing and fixedly coupled with a proximal end of the locking assembly housing; and limiter extending from a sidewall of the locking assembly housing, the leaf spring being operatively coupled with the limiter such that the limiter biases the leaf spring.

In Example 18, the subject matter of Example 17 includes, wherein the locking assembly housing has a post at the locking assembly proximal end and a portion of a proximal end of the leaf spring winds around the post thereby fixedly coupling the leaf spring to the locking assembly housing.

In Example 19, the subject matter of Examples 17–18 includes, wherein the limiter is adjustable within the locking assembly housing such that a spring rate of the locking assembly can be adjusted based on a position of the post within the locking assembly housing.

In Example 20, the subject matter of Examples 17–19 includes, wherein the locking assembly includes an opening at a distal end of the locking assembly, the locking assembly opening configured to a receive a proximal end of the leaf spring.

Example 21 is an apparatus comprising means to implement of any of Examples 1–20.

Example 22 is a system to implement of any of Examples 1–20.

Although teachings have been described with reference to specific example teachings, it will be evident that various modifications and changes may be made to these teachings without departing from the broader spirit and scope of the teachings. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. The accompanying drawings that form a part hereof, show by way of illustration, and not of limitation, specific teachings in which the subject matter may be practiced. The teachings illustrated are described in sufficient detail to enable those skilled in the art to practice the teachings disclosed herein. Other teachings may be utilized and derived therefrom, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. This Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various teachings is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled.