Patent Application
20200096287
Airguns of the break barrel type.
Conventional break barrel air guns provide a stock and receiver that are joined to a barrel by way of a hinge. The receiver houses a spring into which energy is stored, a trigger for releasing the stored energy of the spring to drive a piston into a compression tube having a transfer port that communicates pressure from the compression tube to a breach end of the barrel. In such air guns, the barrel is hingedly joined to the receiver. When the user wishes to use the break barrel airgun, the user rotates the barrel relative to the stock and receiver. This separates the breach end of the barrel from the transfer port allowing a pellet to be loaded therein. After loading the user rotates the barrel to a position where the breech end of the barrel is positioned proximate to the transfer port. The barrel is also connected to the spring in a manner that causes the energy to be stored in the spring as the break barrel is moved during the loading process.
While the acts of rotating the barrel to and from the loading position can be conducted rather quickly. The process of manually loading an individual pellet into the breach end of a barrel while holding an air rifle can be challenging and can extend the time between shots significantly.
What is needed is a break barrel airgun that can load pellets automatically during the cocking action.
Airguns are provided. In one aspect the airgun has a tube fork having front face with a port from which a compressed gas can flow; a barrel having a passageway through the barrel with an opening at a back barrel face, with the passageway sized to receive a projectile, a pivot joining the barrel to the tube fork such that the barrel can be moved between a firing position and a cocking position; a shuttle positioned between the port and the barrel the shuttle having a shuttle passageway with a front end of the shuttle passageway that is larger than at least one of the barrel passageway and the port; a shuttle drive system configured to allow the shuttle to move so that the shuttle passageway is moved between a firing position where a front end of the shuttle passageway overlaps the opening and where a back end of the shuttle passageway overlaps the port and a loading position where the shuttle passageway overlaps a loading opening of a projectile loading system; and, a breech bushing partially in the shuttle passageway and having a breech bushing channel a sized to receive the projectile. The barrel has a barrel guide surface at the back barrel face, the breech bushing has a shaped surface facing the barrel and the breech bushing shaped surface and the barrel guide surface are configured to interact as the barrel is moved from the cocked position to the firing position to urge the breach insert to move within the shuttle passageway in a manner that reduces the extent of any misalignment between the breech bushing channel and the opening.
In the embodiment of
Cocking and loading system 36 can comprise in this embodiment, a barrel 30, tube fork 42, a piston tube 44, a shuttle 54, a shuttle drive 55, a loading mechanism 78, and a bolt latch slider 80. Barrel 30 has a load longitudinal passageway 66 generally extending along a length of barrel 30 beginning at a barrel opening 100 in a barrel back face 102 of barrel 30. Longitudinal passageway 66 is sized to receive projectiles of predetermined length and width and may be of a smooth bore type or may have rifling along some or all of a length of barrel 30. Barrel 30 also has a pivot mount 68 arranged in this embodiment along an axis that is generally orthogonal to the longitudinal axis and sized so that a pivot bolt 60 can pass there through. Barrel 30 is shaped and sized so that a portion of barrel 30 proximate to barrel back face 102 can be positioned between a first fork 92 and a second fork 96 of tube fork 42.
First fork 92 has a first pivot bolt passageway 94 sized to receive pivot bolt 60 while a second pivot bolt passageway 98 is provided in second fork 96 and likewise sized to receive pivot bolt 60. Barrel 30 is assembled to tube fork 42 by aligning pivot mount 68 with first pivot bolt passageway 94 and second pivot bolt passageway 98 to provide a path through which pivot bolt 60 may be inserted. In this embodiment pivot bolt 60 has a screw cap 106 at a first end 108 and a second end 110 to which a pivot nut 48 can be joined. During assembly of barrel 30 and tube fork 42, a spacer 62 and left spur gear 64 are positioned between first end 108 and second end 110 of pivot bolt 60 and second end of pivot bolt 60 is then passed through first pivot bolt passageway 94, pivot mount 68 and second pivot bolt passageway 98. Right spur gear 50 and spacer 46 are then positioned on pivot bolt 60 between second pivot bolt passageway 98 and second end 110. Pivot nut 48 is then joined to second end 110 to provide a predetermined distance between pivot nut 48 and screw cap 106 or to provide a predetermined clamping force between pivot nut 48 and screw cap 106. This arrangement allows barrel 30 and tube fork 42 to pivot relative to each other between a firing position as shown in
A cocking lever 40 is joined to barrel 30 between a first pivot point 112 and an energy storage device such as a spring or gas piston (not shown) such that as barrel 30 is moved from firing position to the cocking position and back energy is stored in the energy storage device. When trigger system 20 is activated, this energy is released to drive a piston toward an inner face 114 of tube fork 42 so as to force compressed air into to a tube fork port 90 that provides a path through tube fork 42 from inner face 114 to outer face 116.
A shuttle 54 is positioned between barrel back face 102 and an outer face 116 of tube fork 42. Shuttle 54 has a shuttle front face 120 confronting barrel back face 102 and a shuttle back face 122 confronting outer face 116 of tube fork 42. Shuttle 54 has a shuttle passageway 124 between shuttle front face 120 and shuttle back face 122. Shuttle drive system 55 is connected to barrel 30 and to tube fork 42 or some other component of air gun 10 that generally remains stationary relative to tube fork 42 as barrel 30 when barrel 30 is moved between the cocked position and the firing position. When barrel 30 is in the firing position as is illustrated in
Shuttle drive system 55 includes a spring cap 58 that is mechanically associated with tube fork 42 for example by way of threading a threaded fastener 130 into a tapped hole 132. Spring cap 58 positions a center pin 56 and shuttle 54 has a center cavity 134 designed to permit sliding motion of shuttle 54 relative to center pin 56 and any structures assembled about center pin 56 such as for example spring type resilient member 138.
As is shown in
The use of such a shuttle 54 for loading provides a projectile that is positioned in shuttle passageway 124 during firing. This in turn requires that effective seals be established between front face of tube fork 42 and shuttle passageway back end 126 of shuttle passageway 124 as well as between shuttle front face 120 and barrel back face 102. Further this arrangement requires precise alignment of tube fork port 90 with the back end of shuttle passageway 124 to prevent turbulent air flows that might consume a portion of the energy in the compressed air supplied from tube fork port 90 during firing. Still further such a system requires that front end of shuttle passageway 124 be precisely aligned with barrel opening 100 of longitudinal passageway 66 of barrel 30. Misalignment at this point can cause turbulent air flow and energy loss as well. However such misalignment also presents the risk that a pellet or other projectile with be partially thrust against barrel back face 102 of barrel 30 which can cause damage to the projectile and causing inaccurate fire or can cause a pellet or other projectile to be jammed at the interface between barrel back face 102 and shuttle 54. Similarly, misalignment of shuttle passageway back end 126 with loading opening 136 can result in damage to a pellet or jamming incidents. Jamming between barrel 30 and loading opening 136 can also occur in the even that a user mistakenly loads more than one projectile into shuttle passageway 124.
It will be appreciated that such misalignment can happen in various ways, along a vertical axis, along a horizontal axis, or both as may occur in the event that shuttle 54 is allowed to slide vertically at a cant and that given the requirements for alignment, thermal and other environmental factors can also impact alignment.
Such concerns place a significant burden on the design of such a system in that a conventional manner of addressing such requirements is to impose exacting constraints on the design of such systems and the materials used such a system. One example of such a system is shown in U.S. Pat. No. 5,772,382, entitled “Loading Plate for a Repeat-Air Rifle for Pellets and Ammunition” issued Orozco, on Mar. 3, 1998. However, such approaches add cost, weight, and complexity which may not be useful in field environments. Alternatively, user adjustment controls can be provided as described in GB978,502 entitled Improvements in or relating to Air or Gas Pressure Guns issued to Vesely et a. and published on Dec. 23, 1964. However, this leads to the need for constant adjustments and creates usability problems.
In the embodiment of loading and cocking system 36 shown here, shuttle 54 is biased by a resilient member 138 that, in this embodiment, is shown as a coil spring that is positioned about pin 56 and that provides a centered thrust urging shuttle 54 away from the firing position toward the loading position. Shuttle 54 provides bilateral shoulders 140 and 142 that are arranged to interact with positioning beams 150 and 152 that project from barrel back face 102 such that as positioning beams 150 and 152 rotate with barrel 30 about pivot bolt 60 through a radius that brings positioning beams 150 and 152 into contact with shoulders 140 and 142 as barrel 30 is rotated from the cocking position to the firing position. The force provided against shoulders 140 and 142 positively drives shuttle 54 against the bias of spring type resilient member 138 to provide bilateral vertical position control over shuttle 54. This further constrains the extent to which canting of shuttle 54 can cause misalignment. Additionally, this provides for vertical positioning of shuttle 54 relative to barrel 30 using reference surfaces that are proximate to barrel 30 and to shuttle passageway 124. This has the effect of limiting the extent to which thermal effects can cause misalignment. It will also be noted that the use, in this embodiment, of beams 150 and 152 with a rounded shape provides tangential contacts with shoulders 140 and 142 such that in the event that foreign materials such as dust, dirt, or grime gets into this system the contact will urge materials away from contact points preserving alignment and positioning.
Even using such an approach, maintaining precise alignment and positioning of a movable slide relative to barrel opening 100 and tube fork port 90 remains challenging. In particular, it is challenging to provide such alignment while maintaining a lightweight and easy to use air gun. For example, if dissimilar materials are used for barrel 30, tube fork 42 and shuttle 54, differences in the rate of thermal expansion can cause differences in alignment that can be difficult to match. As barrel 30 and tube fork 42 are typically made of metal, this tends to require that shuttle 54 likewise be made of metal. Such a decision increases the cost and weight of the air gun 10.
The embodiments of
As shown, breech bushing 52 has a length between front end 160 and back end 170 that is greater than a length between shuttle front face 120 and shuttle back face 122. Further breech bushing 52 has a lateral extension 172 extending outwardly in a direction that is not parallel to a direction of breech bushing channel 164 which may for example take the form of a circumferential flange as shown here or which may take other forms.
In this embodiment, breech bushing 52 is not rigidly joined to shuttle passageway 124 but can move within shuttle passageway 124 within any space provided between breech bushing 52 and shuttle passageway 124. In embodiments, shuttle passageway 124 and breech bushing 52 may be designed so that movement of breech bushing 52 is constrained in certain manners. For example, in this embodiment, breech bushing 52 has a lateral extension 172 extending outwardly in a direction that is not parallel to a direction of breech bushing channel 164 which may for example take the form of a circumferential flange as shown here or which may take other forms and shuttle passageway 124 has a stop 174 positioned therein to interfere with lateral extension 172 to constrain the extent to which breech bushing 52 can move toward front shuttle face 120. This arrangement can be used for example, help retain breech bushing 52 within shuttle passageway 124. Other arrangements are possible.
Further, in this embodiment, where breech bushing 52 has a length between front end 160 and back end 170 that is greater than a length between shuttle front face 120 and shuttle back face 122. This arrangement can be used to help define the extent, if any, to which front end 160 and back end 170 project from shuttle front face 120 and from shuttle back face 122.
As can be seen in
It will be appreciated from this that, in embodiments, the use of this centering interaction between breech bushing shaped surface 162 and barrel guide surface 180 reduces the extent to which the flow of air from port 90 through opening 100 is dependent on the precision placement of shuttle passageway 124. This reduces the extent to which the proper functioning of airgun 10 is dependent on the use of precision cut high density materials heavy and strong materials to form shuttle 54 and on the extent to which shuttle drive 55 must be capable of precision alignment of shuttle channel 124 under all circumstances.
Similarly, the use of a breech bushing 52 that is separate from the shuttle 54 to hold a projectile can also eliminate any requirement that a shuttle 54 be formed from materials that can provide a shuttle passageway 124 that can be repeatedly clamped between opening 100 and port 90 to form effective seals and that can withstand the powerful bursts of pressurized air that must pass therethrough during discharge of airgun 10. For example, it is possible to define shuttle 54, barrel 30, and tube fork 42 in a manner that applies all or a significant proportion of the a clamping force used to make substantially air tight connections with breech bushing 52 without applying such forces to shuttle 54 or while applying a substantially lower amount of such clamping forces to shuttle 54. In one example, the use of the breech bushing 52 having a length between front end 160 and back end 170 that is greater than a length between shuttle front face 120 and shuttle back face 122 enables a longitudinal clamping force to be applied along breech bushing 52 without necessarily causing the same levels of longitudinal clamping force to be applied to shuttle 54. This permits a tight sealing arrangement to be established from port 90 through breech bushing channel 164 to barrel opening 100 without necessarily requiring that shuttle 54 be capable of repeatably experiencing such loads. Other arrangements for applying such force against breech bushing 54 are possible.
The use of breech bushing 52 can also eliminate the need for shuttle 54 to provide a shuttle passageway 124 that can contain the significant gas pressures that may be emitted by port 90.
Instead, only breech bushing 52 need be made of materials that can be relied upon to be repeatedly compressed between barrel 30 and tube fork 42 with the longitudinal force necessary to maintain an effective seal and in embodiments, and that that can survive high pressures. This provides much greater freedom in allowing shuttle 54 to be made using lightweight materials such as polymeric plastics. Additionally system improvements become possible the use of a shuttle drive system 55 that may be less complex or that may require less adjustment as the requirement for precise placement of a heavy object is eliminated and as wear and other factors associated with the challenges of controlling the movement of a heavy shuttle within a confined space may impose. Further, the broader range of materials that can be used to form shuttle 54 may enable other improvements such as where certain polymers are used to form shuttle 54 that may enable improved slip resistance as the shuttle 54 moves against surfaces, for example, and without limitation a surface of tube fork adjacent to port 90.
Loading of the pellet or projectile is accomplished by way of loading mechanism 78. In this embodiment, loading mechanism 78 comprises right spur gear 50 and left spur gear 64, right gear rack 72 and left gear rack 74, left housing 70, right housing 76, bolt latch slider 80 and bolt 86.
Right spur gear 50 is positioned on pivot bolt 60 on a left side of barrel 30 for rotation with barrel 30 about pivot bolt 60. Similarly, left spur gear 64 is positioned on pivot bolt 60 on a left side of barrel 30 for rotation with barrel 30 about pivot bolt 60.
Left housing 70 and right housing 76 are joined together and to tube fork 42 or other components of air gun 10 and provide mountings to which left gear rack 74 and right gear rack 76 can be mounted for slidable longitudinal movement relative thereto. When assembled, left housing 70 and right housing 76 further provide a slide path 188 on which bolt latch slider 80 can be moved longitudinally between a forward and a rear position.
As is shown in
In the embodiment of
In embodiments, the use of breech bushing 52 can allow a common shuttle to be used in airguns having either of a larger caliber barrel or a smaller caliber barrel. In one example of this, the shuttle passageway 124 can be sized larger than either of the larger caliber projectile and the smaller caliber projectile. Where a the common shuttle 54 is to be used with a barrel of the larger caliber, a breech bushing 52 having a breech bushing channel 164 of the larger caliber can be combined with the common shuttle 54. Similarly, where the common shuttle 54 is to be used with a barrel of the smaller caliber, a breech bushing 52 having a breech bushing channel 164 of the smaller caliber can be combined with the common shuttle 54.
In embodiments, breech bushing 52 may have a breech bushing channel 164 with an outer diameter that is larger than the anticipated caliber of projectile to be loaded in to breech bushing 52. Such a breech bushing channel 164 can then taper such that the size of breech bushing channel 164 is about the size of longitudinal passageway 66 at the interface there between.
In embodiments, breech bushing 52 may be adapted to more closely conform to the sizes, shapes or other characteristics of projectiles to be fired by airgun 10. Additionally, breech bushing 52 may be adapted to conform to the characteristics of particular batches or lots of projectiles to be used in airgun 10 and may be supplied by a manufacture with such batches or lots.
Although described as a bushing in the embodiments shown above, it will be appreciated that a breech bushing 52 can take other forms that that can be movably positioned within shuttle passageway to provide functions associated with breech bushing 54.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the scope of the invention.
This application claims the benefit of U.S. Provisional Patent Application No. 62/733,932, filed on Sep. 20, 2018.
| Number | Date | Country | |
|---|---|---|---|
| 62733932 | Sep 2018 | US |
