GB2167538A - Air guns - Google Patents

Abstract

A piston air gun has a safe element, e.g. a slide 16, movable between an "on" position at which a pivoted stop 27 is brought into locking abutment with the camming surface 26 of an element 25 of the trigger mechanism 21 to prevent discharge when the gun is cocked and an "off" position at which the stop 27 is shifted out of said locking abutment. The safe element 16 can be moved manually but is also actuated automatically so that it is shifted from the "off" to the "on" position during cocking action of the gun, e.g. by direct abutment of the rear edge face 15 of the piston 12 at the cocked position of the latter. <IMAGE>

Description

SPECIFICATION Air guns This invention relates to spring-energised high-velocity air guns (e.g. air rifles or air pistols) of the kind operated by a piston which compresses air in a cylinder by spring action so as to eject a projectile from the barrel of the gun, the gun including cocking mechanism enabling the user to move the piston to a fully cocked position ready for release, and trigger mechanism including retaining means for holding the piston at the fully cocked position until the trigger mechanism is actuated by the user to discharge the gun. Guns of this kind are hereinafter referred to as "piston air guns".

The object of the invention is to provide a piston air gun incorporating trigger mechanism having simple and reliable safety means for preventing inadvertent or accidental discharge and which may also have trigger motion which is responsive and precise in use giving exact "feel" of the point of discharge.

According to the invention a piston air gun includes trigger mechanism comprising a manually actuable trigger operable to move the retaining means out of holding engagement with the piston for discharge of the gun, and a safe element moveable independently of the trigger between an "on" position at which said element brings a stop into blocking abutment with some other element of the trigger mechanism to positively prevent trigger actuated movement of the retaining means so as to prevent discharge and an "off" position at which the stop is shifted out of said blocking abutment, the safe element being moveable to the "on" position both manually and automatically, it being actuated at the "off" position by the piston or an element of and/or operating the cocking mechanism during cocking movement near, at o;; beyond their fully cocked position to move the safe element to the "on" position.

Preferably the stop is pivoted for angular movement between said positions and is urged by the safe element into camming engagement with a face of said other element as the safe element approaches the "on" position until it is in overcentre relationship to said other member at said position.

Conveniently the safe element is a slide guided for longitudinal rectilinear movement relative to the cylinder, conveniently at the top rear end of a receiver defining said cylinder, and it is shifted automatically to the "on" position under the action of the piston when the latter is brought to the fully cocked position.

The retaining means of the trigger mechanism may include a main retaining element or sear which releasably engages a formation of the piston at the fully cocked position and an auxiliary retaining element or sear having a catch formation or bent releasably retaining the main sear at its piston engaging position, said auxiliary sear being displaceable by movement of the trigger to release the main sear and free the piston, the trigger acting on a lever arm of the auxiliary sear at a first position remote from its pivot axis during inital trigger movement and at a second position nearer to said axis so that increased trigger pressure is required during a final stage of said movement at which release takes place.

The extent of trigger movement over which said respective engagements take place may be adjustable. Conveniently by a setting screw of the trigger which acts on the arm of the auxiliary sear at the second position.

One embodiment of the invention will now be more particularly described by way of example and with reference to the accompanying drawing being a longitudinal sectional view of part of a break action piston air rifle.

The rifle comprises a cylindrical tubular receiver 10 defining an air cylinder 11 within which a piston 12 is in sliding engagement, the piston being urged forward by a coiled compression main spring (or springs) 13 in known manner.

The barrel (not shown) of the rifle is in operative forward coxial alignment with receiver 10 and is pivoted to provide a break action for loading, this pivoting movement of the barrel shifting a cocking element 14 rearward to bring piston 12 to a fully cocked position as shown in the drawing at which spring 13 is fully compressed and a rear edge face 15 of the piston is adjacent to the rear end of receiver 10.

An upper portion of the extreme rear end of the receiver accommodates a longitudinally moveable safe slide 16 having an exposed thumb grip portion 16a centred above the forward end of a stock 17 of the rifle so that it can readily be operated by left or right handed users.

Slide 16 is shiftable between a forward or "off" position shown in the drawing and a rearward "on" position and its accidental displacement from either position is resisted by a spring loaded ball catch 17. A distinctive marking such as a red dot is exposed to both sides of the rifle to give quick visual recognition of the safe slide position.

When piston 12 is moved rearwards during the cocking action it is shifted somewhat beyond the fully cocked position shown in the drawing. At its extreme rearward position a lower part of edge face 15 engages one end of a pivotally mounted cocking dog 18 projecting through a slot in the lower wall of receiver 10 and this in turn actuates retaining means by raising a pivotally mounted main sear 19 of said means so that an abutment face 20 of this sear enters a notch 21 of the piston.

As the barrel is returned to the in line position cocking element 14 moves forward and piston 12 takes up the fully cocked position shown in the drawing at which it is retained by the engagement of main sear 19 with notch 21. Sear 19 is held in place by other elements of the trigger mechanism retaining means referred to below.

During its extreme rearward travel an upper part of rear edge face 15 of the piston abuts the front face of safe slide 16 shifting it positively to the "on" position if it has been left "off" i.e. if it has not already been set "on" manually prior to cocking.

The trigger mechanism of the rifle further includes a trigger 21 having a finger actuated arm 22 projecting downwardly within a trigger guard 23 in the usual way, a forward projection of the trigger mounting it for pivotal movement on a cross pin 23 which also carries a light torsion spring 24 providing a small biasing force urging the trigger anticlockwise as viewed in the drawing. Trigger 22 includes an upward extension 25 horizontally offset from the axis of pin 23 and projecting through the slot in receiver 10 to present an angled camming face 26 spaced below slide 16.A pivoted safe toggle 27 has an upper arm 28 engaged in a vertical bore in slide 16 so that movement of the latter is transmitted into angular movement of the toggle, and a lower arm 29 whose end is clear of face 26 when slide 16 is at the "off" position shown in the drawing but which abuts said face to displace trigger 22 clockwise against spring 24 as the slide is shifted to the "on" position. The end of arm 29 rides over the camming face 26 until it rests on a forward slope thereof with arm 29 over vertical to give an over-centre movement which positively prevents anti-clockwise displacement of trigger 22 and which further assists in retaining slide 16 and toggle 27 at their "on" positions.

The discharging action of the trigger mechanism will now be described with the safe means at the "off" position shown in the drawing so that trigger 21 is free for movement.

Main sear 19 includes a generally horizontal rearwardly extending tail portion 30 extending beyond the cocking dog 18 and having a distal end which is engaged by an upwardly directed lip 31 forming a retaining bent on a generally vertical arm of a bell crank shaped auxiliary sear 32, a horizontal arm 32a of the latter being acted on by trigger 22. When the trigger is pulled sear 32 will be rotated clockwise as viewed in the drawing against the force of a torsion spring 33 until its bent, in particular lip 31, frees the tail portion 30 of the main sear 19 letting it drop until face 20 is free of notch 21 in the piston, freeing the latter for forward movement in discharge of the rifle. Main sear 19 is urged downward by another torsion spring 35 and its freeing from the piston is further assisted by abutment face 20 and the coacting face of notch 21 being angled.

When the rifle is re-cocked the action of cocking dog 18 raises the main sear 19 so that its distal end rides past an angled face below lip 31 to displace sear 32 angularly against spring 33 until tail portion 30 reengages the bent formation.

This trigger mechanism is provided with a two stage "pull off" giving a light but detectable pretravel "feel" approaching the point of release and a short heavier pull up to release itself so that the user can tell from the feel of the trigger when the release point is near. This trigger action is provided by trigger 21 having two points of engagement with the horizontal arm 32a of auxiliary sear 32. Initially a face 36 on the trigger engages the distal end of arm 32a giving maximum leverage and hence the lighter action but as angular movement of trigger 22 continues anti-clockwise the tip of a setting screw 37 of the trigger engages a median portion of arm 32a i.e. nearer to its pivot axis, giving a heavier pull just before lip 31 frees main sear 19.The extent of the heavier pull can be selectively adjusted by the user by altering the depth of engagement of screw 37 which is accessible without dismantling the rifle by means of a screwdriver inserted from below.

It is to be noted that the rifle can be made safe by the use of slide 16 whether or not it has been cocked; it will be automatically set safe when first cocked as referred to above; and further that if the safe is moved to the "off" position with the intention of discharging the rifle but discharge does not take place, e.g. if hunting live game, because the target has moved, the gun can be made safe again by restoring slide 16 to the "on" position without discharge taking place and with the rifle remaining cocked ready for use. Thus the invention provides particularly convenient and responsive operation coupled with maximum safety in preventing inadvertant or accidental discharge and sensitively responsive and controlled trigger action.

It is to be understood that the invention may be incorporated in other forms of distant air guns, for example rifles having lever action cocking instead of brake action, and pistols having various cocking actions.

It is also to be understood that the safe element may be arranged to be automatically set "on" directly or indirectly by any part of the cocking mechanism as it approaches near to, is at, or is moved beyond the fully cocked position during cocking movement though the rear edge face of the piston is convenient as described above. Thus in some constructions the safe element or an element such as the safe toggle 27 linked for movement therewith, may be acted on directly or indirectly by cocking element 14 or some part of piston 12 other than its rear face or some part of some other components, e.g. the barrel of the gun or a cocking lever in a gun not having break action cocking.

Claims (13)

1. A piston air gun including trigger mechanism comprising a manually actuable trigger operable to move the retaining means out of holding engagement with the piston for discharge of the gun, and a safe element moveable independently of the trigger between an "on" position at which said element brings a stop into blocking abutment with some other element of the trigger mechanism to positively prevent trigger actuated movement of the retaining means so as to prevent discharge and an "off" position at which the stop is shifted out of said blocking abutment, the safe element being moveable to the "on" position both manually and automatically, it being actuated at the "off" position by the piston or an element of and/or operating the cocking mechanism during cocking movement near, at or beyond its or their fully cocked position to move the safe element to the "on" position.

2. An air gun as in Claim 1 wherein the stop is pivoted for angular movement between the "on" and "off" positions.

3. An air gun as in Claim 2 wherein the stop is urged by the safe element into camming engagement with a face of said other element as the safe element approaches the "on" position.

4. An air gun as in Claim 3 wherein the stop is in over-centre relationship to said other member at the "on" position.

5. An air gun as in any preceding claim wherein the safe element is a slide guided for longitudinal rectilinear movement relative to the cylinder.

6. An air gun as in Claim 5 wherein the slide is mounted at the top rear end of a receiver defining said cylinder and is shifted automatically to the "on" position under the action of the piston when the latter is brought to the fully cocked position.

7. An air gun as in any preceding claim wherein the element of the trigger mechanism with which the stop abuts at the "on" position is the trigger itself.

8. An air gun as in any preceding claim wherein the retaining means of the trigger mechanism includes a main retaining element or sear which releasably engages a formation of the piston at the fully cocked position and an auxiliary retaining element or sear having a catch formation or bent releasably retaining the main sear at its piston engaging position, said auxiliary sear being displaceable by movement of the trigger to release the main sear and free the piston.

9. An air gun as in Claim 7 wherein the trigger acts on a lever arm of the auxiliary sear at a first position remote from its pivot axis during initiai trigger movement and then at a second position nearer to said axis so that increased trigger pressure is required during a final stage of said movement at which release takes place.

10. An air gun as in Claim 8 wherein the extent of trigger movement over which said respective engagements take place is adjustable.

11. An air gun as in Claim 9 wherein the adjustment is effected by a setting screw of the trigger which acts on the lever arm of the auxiliary sear at the second position.

12. An air gun as in any preceding claim in the form of a break action air rifle.

13. An air gun substantially as hereinbefore described with reference to and as shown in the accompanying drawings.