WO2023177817A1

WO2023177817A1 - Air gun with integrated air compressor

Info

Publication number: WO2023177817A1
Application number: PCT/US2023/015410
Authority: WO
Inventors: Jeffrey Hanson; William Mathias
Original assignee: Crosman Corporation
Priority date: 2022-03-16
Filing date: 2023-03-16
Publication date: 2023-09-21

Abstract

An air gun includes a barrel through which a projectile is fired and a chamber fluidly connected to the barrel. The air gun also includes an onboard air compressor configured to charge the chamber with compressed air. The air compressor is coupled to a motor driving a crank that cycles a piston in the air compressor to generate the compressed air.

Description

AIR GUN WITH INTEGRATED AIR COMPRESSOR

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority of US Provisional Patent Application No. 63/320,514, filed March 16, 2022, and entitled “Air Gun with Integrated Air Compressor,” the entire disclosure of which is hereby incorporated by reference in its entirety.

BACKGROUND

[0002] Air guns are used for a variety of recreational purposes. Some types of air guns require manual interaction to ready the gun for firing. For instance, conventional break-barrel guns require a user to manually compress a spring by pivoting the barrel proximate the breech of the gun. Some pneumatic guns require a user to manually increase air pressure in a chamber, e.g., by pumping, or the like. These conventional designs can become fatiguing for some users and readying these guns for firing may be time consuming. Other conventional air guns include a tank or reservoir that is charged (e.g., pre-charged) to provide a number of shots before re-charging. However, these pre-charged pneumatics require downtime for charging, and may have variable air pressure over the life of a charge, e.g., because air pressure in the tank decreases as shots are fired. Thus, there is a need in the art for an improved air gun that does not require conventional manual interaction for charging and that does not suffer the drawbacks of pre-charged pneumatics.

BRIEF DESCRIPTION OF THE DRAWINGS

[0003] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit of a reference number identifies the figure in which the reference number first appears. The same reference numbers in different figures indicate similar or identical items.

[0004] FIG. 1 is side view of an example air gun according to example implementations of this disclosure.

[0005] FIG. 2 is a perspective view of the air gun of FIG. 1, according to example embodiments of the present disclosure.

[0006] FIG. 3 is a block diagram of an air gun, according to example embodiments of this disclosure.

[0007] FIG. 4 shows example user interfaces for an air gun, according to example embodiments of this disclosure.

[0008] FIG. 5 is a block diagram of an air gun, according to example implementations of this disclosure.

DETAILED DESCRIPTION

[0009] FIG. 1 illustrates an example self-pumping pneumatic air gun 100 according to aspects of this disclosure. More specifically, FIG. l is a side view of one implementation of the air gun 100, which includes features for self- or automatic-pneumatic charging via an on-board air compressing system. FIG. 1 illustrates the air gun 100 as generally including a barrel 102, a stock 104, and a trigger 106. The air gun 100 also includes a housing 108 extending generally between the barrel 102 and the stock 104, although portions of the housing 108 are shown in cross-section and/or omitted entirely for clarity in FIG. 1. The housing 108 may retain and/or conceal components of the air gun 100, including a compressor 110 for fdling a charge volume 112 with compressed air for firing a projectile from the barrel 102. The air gun 100 also includes a drive system 114 for actuating the air compressor 110 to generate the compressed air. Without limitation, aspects of this disclosure include components for self- or automatic-cocking of the air gun 100, which may be disposed in, attached to, or otherwise associated with the housing 108. In aspects of this disclosure, the housing 108 may be any portion of the air gun 100 that contains, retains, mounts, or otherwise couples to other aspects of the air gun. In some examples, the housing may be a portion of the air gun 100 that conceals, covers, and/or shrouds other aspects of the air gun. For example, the housing 108 can include some or all of the stock 104, the barrel 102, and/or a central body of the air gun between the stock 104 and/or the barrel.

[0010] The barrel 102 extends generally from a breech end to a muzzle end. Although not illustrated in FIG. 1, a bore extends through the barrel 102, from the breech end to the muzzle end. The bore provides a hollow interior space within the barrel 102 through which compressed air and a projectile, such as a pellet, can pass, as will be described in greater detail below. The barrel 102 is sufficiently strong to contain high pressure gasses introduced into the barrel 102 to fire the projectile. In implementations, the bore may be smooth, or the bore may be rifled, e.g., to impart a stabilizing spin on the projectile as it passes through the bore.

[0011] The stock 104 may be any conventional size or shape. In some instances, the stock 104 may be removably secured to the housing, e.g. to promote removal and/or replacement of the stock 104. Moreover, removal of the stock 104 may facilitate access to an interior of the housing 108, e.g., to service working components of the air gun 100, and may also house a battery or other power source, a control system adapted to receive inputs from sensors and/or to generate outputs that drive motors, actuators, lights, solenoids, motors, linear actuators and/or other electronic, mechanical, electromechanical, sonic, electrooptical, and/or other components. Without limitation, the stock 104 may comprise a portion of the housing 108. [0012] The trigger 106 may be any lever, button, or the like, configured for user interaction to fire the air gun 100. As detailed further herein, in some instances the trigger 106 is a part of a trigger assembly that, among other features, prevents unintended firing of the air gun 100. For example, and without limitation, a trigger assembly including the trigger 106 may prevent firing of the air gun 100 while the air gun 100 is compressing air after firing a projectile.

[0013] The housing 108 is generally provided to contain components of the air gun 100. For instance, and as detailed further below, the housing 108 may contain, support, and/or conceal aspects that facilitate automatic pumping and/or action of the air gun 100. The shape and size of the housing 108 in FIG. 1 is for illustration. Other shapes, sizes, and compositions are contemplated. Components of the housing may be made of any conventional materials, including but not limited to, metal, such as aluminum, or polymers.

[0014] The air compressor 110 is configured to compress air to a pressure sufficient to fire a projectile from the barrel 102 of the air gun 100. In examples, the air compressor 110 can be configured to compress air from about 1500 psi to about 2000 psi. In some instances, the air compressor 110 can be an axial piston compressor, e.g., that compresses air via axial movement of a piston in a cylinder. The air compressor 110 may be a multi-stage compressor, e.g., a two- stage axial piston compressor in some examples. Air compressed by the air compressor 110 is stored in a charge volume 112, e.g., until the trigger 106 is actuated causing the air gun 100 to fire. More specifically, an outlet of the charge volume 112 is fluidly connected to the barrel 102, with actuation of the trigger 106 causing the compressed air in the charge volume 1 12 to escape from the air gun 100 through the barrel 102.

[0015] The drive system 114 includes components configured to cause the air compressor 110 to generate the compressed air. In the illustrated example, the drive system 114 includes a motor 1 16, a gearbox 118, a gearset 120, and an eccentric crank 122. Tn this embodiment, the gearbox 118, gearset 120, and the eccentric crank 122 comprise power transmission components to transmit the rotational motion of a shaft of the motor 116 to drive a piston of the air compressor 110. In other embodiments, motor 116 can drive any known or yet to be developed form of air compression mechanism.

[0016] The motor 116 may be a DC motor, e.g., powered by one or more batteries, or any other form of electrically powered motor including but not limited to a brushed or brushless DC motor, an alternating current motor, an induction motor, any other known system for converting electrical energy into kinetic motion. In other embodiments, the motor 116 may be a fuel operated engine. Although not illustrated in FIG. 1, the motor 116 includes a shaft that selectively rotates at a predetermined rotational velocity and/or torque. In one non-limiting example the motor 116 may be a 12-18 volt DC motor. The motor 116 may have a size selected to fit within the housing 108. In one non-limiting example, the motor 116 may have a diameter of from about 25 mm to about 50 mm. For example, the motor 116 may have a diameter of about 38 mm.

[0017] The gearbox 118 is coupled to the shaft of the motor 116. For example, the gearbox 118 may include a gearing ratio that provides increased torque. In examples, the gearbox 118 may be a planetary gearbox. The gearbox 118 may have a ratio of 50: 1 or higher. In one example, the planetary gearbox may have a ratio of about 71: 1. The gearbox 118 may be a multiple stage gearbox, e.g., a two-stage gearbox.

[0018] The gearset 120 may be provided to couple the gearbox 118 to the eccentric crank 122.

In the example, an axis of the shaft of the motor 116 is substantially parallel to an axis of a piston of the air compressor 110. The gearset 120, together with the eccentric crank 122, transfer the rotation of the motor 116 to a linear motion, laterally displaced from the axis of the shaft of the motor 1 16. More specifically, in the illustrated example, the gearset 120 is a miter gearset including a first gear 124 and a second gear 126 configured to rotate about axes of rotation 90- degrees relative to each other. Thus, the gearset 120 transfers rotation by 90-degrees, e.g., from a rotation about a horizontal axis to a rotation about a vertical axis in the illustration of FIG. 1. In examples, the gears 124, 126 may have any ratio, e.g., depending on the preferred transmission. In some examples, the gears 124, 126 may have a ratio of 1 : 1, 2: 1, 1 :2 or something else.

[0019] The eccentric crank 122 generates linear motion from the rotational motion of the second gear 126. Specifically, and as better seen in FIG. 2, the eccentric crank 122 includes a sheave or disk 128 having a center of rotation offset from the rotational axis of the second gear 126. The eccentric crank 122 also includes an eccentric rod 130 coupled to the disk 128. An end of the rod 130 is coupled to the disk 128 to pivot in response to rotation of the disk 128. For instance, the end of the rod 130 may be coupled to a pivot about a rotational axis of the disk 128, which, as noted above, is parallel to, but not coaxial with, the rotational axis of the second gear 126. Accordingly, a distal end of the rod 130, e.g., an end of the rod opposite the end coupled to the disk 128, will move substantially along a linear dimension shown by the arrow 132. Although obscured in FIG. 1 by a housing of the air compressor 110, the distal end of the rod 130 is coupled to a piston shaft of the air compressor 110. The eccentric crank may be designed to stroke the air compressor 110 each revolution of eccentric disk 128. Without limitation, the diameter of the eccentric disk 128 may be configured to be about equal to the stroke of the piston in the air compressor 110.

[0020] According to the illustrated arrangement, the gearbox 118 increases a torque of a rotational output of the motor 116. The gearset 120 transmits the output of the gearbox 118 to the eccentric crank 122 to drive the piston of the air compressor 110. This arrangement is one example arrangement that may facilitate charging of the air compressor 1 10, e.g., via an onboard air compressor 110. For example, although the motor 116 is shown below, e.g., in a vertical direction in the orientation of FIG. 1, the air compressor 110, in still further examples the motor 116 may be generally aligned with the compressor. Other arrangements also are contemplated. Moreover, although the example utilizes the gearbox 118, gearset 120, and eccentric crank 122 to transmit the rotation of the motor 116 to the air compressor 110, in other examples different transmission setups may be used.

[0021] As also shown in FIG. 1, the air gun 100 can include a power source 134, e.g., one or more batteries and a control unit 136, e.g., embodied as a printed circuit board in FIG. 1. The power source 134 may be rechargeable batteries, e g., charged by removing a battery pack or by coupling a power supply thereto, e.g., during non-use of the air gun 100. In other examples, the batteries may be replaceable, e.g., disposable. In at least some instances, the power source 134 may provide power to the motor 116, as well as to other electronic components of the air gun 100, as detailed further herein.

[0022] The control unit 136 is embodied in FIG. 1 as a printed circuit board. The control unit 136 may be configured to control aspects of the air gun 100. Additional details of the control unit 136 are discussed below, in connection with FIG. 5, which is a block diagram of aspects of the control unit 136.

[0023] FIG. 1 also illustrates that the air gun 100 can include a user interface 138. The user interface 138 is illustrated as including a number of buttons, switches, or similar interface elements that may be used to control aspects of the air gun 100. An example of the user interface 138 is illustrated in FIG. 4, described in more detail below.

[0024] FIG. 2 is a perspective view of the air gun 100 of FIG. 1. The same reference numerals are used in FIG. 2 to illustrate the same features. FIG. 2 shows more clearly the eccentric rod 130 and the control unit 136 (embodied schematically as a printed circuit board) as well as the layout of some other components.

[0025] FIG. 3 is a schematic diagram 300 showing aspects of the air gun 100, e.g., showing aspects of an example of the air compressor 110 in more detail. In the example of FIG. 3, the motor 116 and the gearbox 118 are shown as combined in a single component connected or coupled to the gearset 120, which in turn, is connected or coupled to the eccentric crank 122. The eccentric crank 122 is connected or coupled to a piston 304 of the air compressor 110. The air compressor 110 is illustrated as a two-stage pump. More specifically, the air compressor 110 includes a first stage 306 configured to pressurize ambient air entering via an inlet, e.g., on a down stroke of the piston 304, and to convey this air pressurized by the first stage 306 to a second stage 308 that further compresses the air, e.g., on a return stroke of the piston 304, for storing in the charge volume 112. In examples, the charge volume 112 may be on the order of about 0.25 to about 2.5 cubic centimeters, and may store compressed air at a pressure of about 300 psi to about 10,000 psi, and more specifically at a pressure of from about 1500 psi to about 2000 psi. The example of FIG. 3 also shows three one-way valves, e.g., a first, inlet valve 310, through which ambient air enters the first stage 306, a second valve 312 through which air compressed by the first stage 306 is passed to the second stage 308, and a third valve 314 through which air passes from the second stage 308 to the charge volume 112. FIG. 3 also schematically illustrates conduits, e.g., tubing or piping, via which the air passes into, through, and out of the air compressor 110.

[0026] FIG. 3 also shows a firing valve 316. The firing valve 316 is a valve that may be selectively actuated to allow the pressurized air to exit the charge volume 112 and exit the air gun 100 through the barrel (shown in FIG. 1). As detailed further below, the firing valve 316 may be controlled in response to a user pulling the trigger 106. Mechanical, electro-mechanical, electro- optical, pneumatic and/or hydraulic systems can be used to control firing valve 316 in response to the pulling of trigger 106.

[0027] FIG. 4 shows examples of a first user interface 400 and a second user interface 402, which may be examples of the user interface 138. The user interfaces 400, 402 include features to enable similar or the same functionality of the air gun 100. Specifically, the user interfaces 400, 402 include a power control 404, a status indicator 406, a mode selector 408, and a manual cycling control 410.

[0028] The power control 404 may be a switch configured to selectively power on the air gun 100. In the first user interface 400, the power control 404 is a rocker switch, whereas in the second user interface 402, the power control 404 is a button. Other types of switches or user interface elements, e.g., knobs, switches, tactile interfaces, or the like, may be used in place of or in addition to the illustrated examples. As noted, user interaction with the power control 404 will cause the air gun 100 to be selectively powered on/off.

[0029] The status indicator 406 is embodied in the user interfaces 400, 402 as a light emitter. Specifically, the status indicator 406 may be an LED that is selectively colored to indicate a status of the air gun 100. Without limitation, the status indicator may emit a red light when the air gun 100 is ready for firing, e.g., to indicate that the air gun 100 is energized or armed, and may emit a green light when the air gun 100 is not ready for firing, e.g., because the air compressor is cycling, the charge volume 112 empty, no pellet or projectile is detected, the air gun 100 is jammed, or otherwise. Other colors may be used to indicate different statuses of the air gun 100. In still further embodiments, the status indicator 406 may output light patterns, e.g., intermittent flashing or blinking, to identify different statuses of the air gun 100. Although the example interfaces 400, 402, embody the status indicator 406 as a light, other examples can include a textual output, e g., via a display, an audible emitter, e.g., a speaker, and/or other arrangements configured to convey a status of the air gun 100 to the user.

[0030] The mode selector 408 is a switch that allows the user of the air gun 100 to select a firing configuration for the air gun 100. In the example of FIG. 4, the mode selector 408 allows a user to select between automatic pumping/charging of the charge volume 112 and manual pumping/charging of the charge volume 112 of the air gun 100. In the automatic mode, the air gun 100 may be configured to automatically cycle after the air gun 100 is fired, e.g., when the trigger is pulled, when a pressure drop in the charge volume 112 is detected, when sensor data, such as accelerometer data, indicates that the air gun 100 has been fired, or the like. In the manual mode, the user may have to take some affirmative action, e.g., interacting with the manual cycling control 410, to cycle the air gun 100, as described below. In other examples, additional and/or different modes may be selectable via the mode selector 408. For instance, other modes may include a mode that allows for a predetermined number of automatic cycles, e.g., two, three, or the like.

[0031] The manual cycle control 410 may be a button or other interface that facilitates cycling of the air compressor 110. For instance, with the air gun 100 in the manual mode, the user may have to press or otherwise interact with the manual cycle control 410 to cause the air compressor 110 to refill the charge volume 112.

[0032] The user interfaces 400, 402 may include additional and/or alternative features for controlling aspects of the air gun 100. Without limitation, the user interfaces 400, 402 may include a pressure adjustment control, e.g., that allows the user to select a pressure for charging the charge volume 112. [0033] FIG. 5 shows a block diagram 500 representing an example of the control unit 136. Specifically, the block diagram 500 shows that the control unit 136 receive inputs from the power control 404, the mode selector 408, and the manual cycle control 410, and power from the power source 134. The control unit 136 also provides outputs to the motor 116 and to the status indicator 406. The control unit is illustrated as including a firing sensor 502, a power charge sensor 504, a motor driver 506, and a CPU/controller 508.

[0034] The firing sensor 502 can include functionality to determine a status of the air gun 100. For example, the firing sensor 502 can include an accelerometer that detects movement of the air gun 100 consistent with firing of the air gun 100. In another example, the firing sensor 502 can include a pressure sensor or pressure transducer that generates data that can be used to determine that the pressure in the charge volume 112 has dropped in accordance with the firing of the air gun 100. For instance, information that the air gun 100 has been fired may be used to cause the air gun 100 to be cycled, e.g., when the air gun 100 is in an automatic firing mode.

[0035] The power charge sensor 504 can include functionality to determine an amount (or sufficiency) of power available to the air gun 100. For instance, the power charge sensor 504 can include functionality to determine a charge of batteries used as the power source 134. For example, a low battery state may be conveyed to the user via the status indicator 406.

[0036] The motor driver 506 includes functionality to drive the motor 116, e.g., to cycle the air compressor 110 to ready the air gun 100 for firing. In examples, the motor driver 506 can be a motor drive circuit that receives a signal to cause the motor to activate for a predetermined time and/or until the pressure in the charge volume 112 meets a target pressure to cycle the air compressor 110, as detailed herein.

[0037] The CPU/controller 508 includes the functionality to effectuate the processes detailed herein. Specifically, the CPU/controller 508 can include processors, circuitry, and/or the like for implementing logic and/or programming instructions, e.g., stored on memory, to control aspects of the air gun 100. For example, the CPU/controller 508 may receive the inputs, and based on the inputs, cause the status indicator 406 to indicate a status of the air gun, e.g., ready for firing, jammed, cycling, low battery, or the like. The CPU/controller 508 may also cause the motor driver 506 to drive the motor 116 to cycle the air compressor 110, e.g., based on receiving a signal corresponding to actuation of the manual cycle control 410, based on receiving information from the firing sensor 502 that the air gun 100 has been fired and the selected mode is an automatic firing mode, or the like. In embodiments, a current sensor can be used to sense current flowing to the motor 116 and generate an output signal from which CPU/controller 508 may determine current levels during pumping operations to detect current levels or patterns of change of current levels over time that indicate that a predetermined air compressed pressure level has been reached. [0038] The subject matter described above is provided by way of illustration only and should not be construed as limiting. Furthermore, the claimed subject matter is not limited to implementations that solve any or all disadvantages noted in any part of this disclosure. Various modifications and changes may be made to the subject matter described herein without following the examples and applications illustrated and described, and without departing from the spirit and scope of the present invention, which is set forth in the following claims.

Claims

We claim:

1. An air gun comprising: a housing; a barrel; a chamber disposed in the housing in fluid communication with the barrel, the chamber storing compressed air for firing the air gun; an air compressor disposed in the housing and in fluid communication with the chamber for generating the compressed air; and a drive system disposed in the housing and including a motor, the drive system being configured to cycle the air compressor to fill the chamber with the compressed air.

2. The air gun of claim 1, wherein the drive system comprises one or more power transmission components for transferring a rotational motion of a shaft of the motor to the air compressor.

3. The air gun of claim 2, wherein the power transmission components comprise one or more gears configured to increase a torque of an output of the motor.

4. The air gun of claim 3, wherein the one or more gears comprise a planetary gearbox.

5. The air gun of claim 2, wherein: the air compressor comprises a piston configured to move relative to at least one cylinder; the power transmission components comprise a crank coupled to the piston of the air compressor and to the shaft of the motor; and rotation of the shaft of the motor causes the crank to move the piston of the air compressor relative to the at least one cylinder of the air compressor.

6. The air gun of claim 5, wherein: the air compressor is a two-stage air compressor comprising a first cylinder and a second cylinder fluidly coupled to the first cylinder; the piston is configured to move relative to the first cylinder and relative to the second cylinder; and the first cylinder has a first volume and the second cylinder has a second volume different from the first volume.

7. The air gun of claim 5, wherein the crank is an eccentric crank.

8. The air gun of claim 1, wherein: the motor has a shaft configured to rotate about a first axis; the air compressor comprises a piston configured to move along a second axis; and the first axis and the second axis are other than coaxial.

9. The air gun of claim 8, wherein the first axis is substantially parallel to the second axis.

10. The air gun of any of claim 1 through claim 9, further comprising: a control unit configured to: receive a first signal associated with a command to cycle the air compressor to charge the chamber with compressed air; and transmit a second signal to the motor to cause the motor to cycle the air compressor.

11. The air gun of claim 10, further comprising: a firing sensor configured to determine when the air gun has been fired and generate the first signal based on determining that the air gun has been fired.

12. The air gun of claim 11, wherein the firing sensor comprises a pressure sensor configured to determine a pressure in the chamber.

13. The air gun of claim 11 , wherein the firing sensor comprises an accelerometer configured to determine a movement of the air gun consistent with firing of the air gun.

14. The air gun of claim 10, further comprising a user interface element configured for actuation by a user, the user interface element being configured to generate the first signal in response to actuation of the user interface element.

15. The air gun of claim 10, further comprising an indicator configured to indicate to a user whether the air gun is ready for firing, wherein the indicator is at least one of a visual indicator or an audible indicator.