ENCLOSURE FOR SHOOTER

Abstract

The enclosure surrounds the shooter who fires his/her weapon from inside, adjacent the back wall, at a target and/or bullet trap located some distance away from the enclosure. Sole access to the enclosure, and the shooter's station therein, is through the open front end. Air circulation and filtration is supplemented by generating an air curtain across the open front end. Air venting and filtration of inside air is at a rate of 6 times per minute and provides a flow of clean air from back to front of the enclosure through a pressurized plenum in the back wall designed to create a uniform flow through the shooter's station. An auxiliary venting outlet in the top or ceiling of the enclosure provides a negative air pressure inside the enclosure so contaminated air escaping through the open front end is minimized.

Description

BACKGROUND OF INVENTION

This application incorporates by reference U.S. Patent Provisional Application Ser. No. 61/827,136 filed May 24, 2013 and claims priority thereto in so far as common subject matter/invention is included.

Shooting ranges generally require considerable real estate to accommodate a shooter sitting or standing and firing his weapon at a target located 25 or more feet from the shooter. Shooting clubs and firing ranges are sometimes fully enclosed, and equipped with air exchanging capability, plus, they must provide access to the target area, all factors that further increase the need for considerable real estate, whether located inside a building or outside.

There is a need, therefore, for a shooter's enclosure that can be used with a compact bullet trap, in a residential basement, or other confined space, and yet provide for both noise reductions and accommodate the waste products of firing weapons, and satisfy the environmental concerns of even the most fastidious homeowner. Such concerns are met with an enclosure having the features to be described.

The present invention provides an enclosure that satisfies these concerns, and that can be used with a bullet trap of suitable design. The inventor refers to his co-pending application Ser. No. 13/475,511 filed May 18, 2012 for a description of such a bullet trap. That co-pending application is incorporated by reference herein.

SUMMARY OF THE INVENTION

In accordance with the present invention a generally rectangular walled structure is provided with a single access opening at the front end thereof. This open front end is aligned with and faces the bullet trap, and inside of the enclosure, adjacent the back wall, a shooter's station is provided at some predetermined distance from the target area of the bullet trap.

The inside of the enclosure is maintained at a slight negative air pressure relative to the ambient air external to the enclosure. Air in the enclosure is circulated through a closed system where it is filtered, and some air from inside the enclosure is vented outside of the enclosure, and/or outside of the building in which the enclosure is located.

The air circulation and filtration system supplies filtered air to a pressurized plenum built into the back wall, and delivers a uniform air flow from back to front of the rectangular enclosure. An air curtain is created across the enclosure adjacent to the front end, by means of a blower inside a housing designed for this purpose, and located on one side wall of the enclosure. On the opposite wall of the enclosure, air is drawn into a housing where it is filtered and re-circulated, for return to and pressurizing of said plenum located in the back wall of the enclosure.

Among the many unique features of the shooter's enclosure, the following are particularly significant: first, baffles are provided on the side walls, to better absorb the noise generated by the firearm, and by reason of the location selected for said baffles the air flow inside the enclosure is more closely controlled, assuring that any flow through the open front end is minimized. Second, air dams are provided just downstream of the shooter's station to increase airflow velocity in this area. This assures that gasses created during firing of the weapon are not allowed to collect in the area of the shooter's station where the shooter might otherwise suffer the ill effects of the noxious fumes generated by successive firings inside the enclosure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 shows, schematically and in perspective, an enclosure with an open front end, and air re-circulating and venting apparatus in selected locations for maximizing the advantages of my invention.

FIG. 2 shows, in horizontal section, the enclosure of FIG. 1, illustrating the interior features thereof.

FIG. 3 is a perspective view looking into the front end of the enclosure to the shooter's station.

FIG. 4 is an exploded view of the components comprising the plenum chamber in the rear wall of the enclosure.

FIG. 5 shows the components depicted in FIG. 6 as assembled.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT

Referring now to FIG. 1 in greater detail, the rectangular enclosure is preferably made largely from conventional components, many of which are available from suppliers such as STANCO, a supplier of sectional enclosures, SOUNDSEAL, a supplier of sound deadening blankets, and MARSAIR, a supplier of air curtain generating equipment.

In it's presently preferred form the enclosure is rectangular in plan-form, with side walls 10 and 12, supporting a top wall 14. The back wall 16 defines a plenum chamber in which mutually perpendicular grids, 18 and 20, provide a grid structure into which air is forced into the rear grid 18, as suggested by the arrows 22, 22, and then into the front grid 20, and through a grille 26, from pressurized air in a plenum chamber 24 located at the back of the enclosure and described in detail with reference to FIG. 4.

The grid structure of FIG. 4, serves to turn the air flow from the initial direction 22, to a downstream direction as indicated by the arrows 28,28 in FIG. 2. Horizontal dividers of rear grid 18 and front grid 20, have a foraminous sheet 25 sandwiched between these grids to create a generally uniform flow of air from the back toward the front inside the enclosure. The grille 26 and grid structure of FIG. 4 occupy the entire back wall of the enclosure for this purpose. See the arrows 28,28 for a schematic attempt to illustrate this airflow pattern.

The grid structure of FIG. 4 defines the plenum chamber 24 in the rear wall 16 of the enclosure behind the shooter's station. Two foraminous sheets 25 and 27, best shown in FIG. 5, cooperate with the grid structures, 18 and 20, to divert the air flow from the incoming direction of arrows 22, 22 through the grille 26 to the downstream direction as suggested by arrows 28,28. The rear most wall 33 of the enclosure is solid and in cooperation with the sides and top walls of the enclosure defines the plenum chamber 24.

FIG. 2 shows a shooter's station, with a table 30 behind which the shooter positions himself for firing out through the open end 32 of the enclosure at a target, and/or bullet trap located a predetermined distance from the shooter's station outside the enclosure. Preferably, suitable warning systems are placed in the general area of the enclosure and the target/bullet trap so as to avoid injury to persons or property in this general area. Motion detectors are recommended for placement at strategic locations in this area, and warning devices inside the enclosure (aural and visual) alert the shooter to such intrusions and the need for cease firing from inside the enclosure. Thus the front end of the enclosure defines a relatively large opening 32 for accommodating the shooter's visual field of the target/bullet trap.

In further accordance with the present invention, and to prevent noxious fumes and other products of combustion from the fired weapon escaping from the enclosure, the interior of the enclosure is maintained at a slight negative pressure relative to ambient pressure outside the enclosure. Additionally, and to protect the shooter from these noxious gasses of combustion and particulates hostile to his environment, several design features serve to minimize these environmental hazards as follows; The downstream air flow pattern inside the enclosure carries these gasses and hazardous particles away from the shooter's station, where these gasses and entrained particles can be collected by air circulation and filtration units to be described.

The majority of ventilation air will be drawn into a collection chamber 34 for return to the plenum chamber 24 associated with the back end wall 16 of the enclosure. To create the desired negative ambient air pressure inside the enclosure, an air-venting unit 36 is provided in the top wall of the enclosure adjacent to the open front end, and a vent pipe allows air from unit 36 to escape from the enclosure as suggested by the arrows 38, 38 to the outside world, that is, outside of any building in which the enclosure is placed for example. Thus a slight negative pressure is maintained inside the enclosure.

The air re-circulating unit, or units, associated with the chamber 34 have multiple filters that can be replaced periodically in accordance with regularly scheduled maintenance protocols. So too, the vent unit 36 is fitted with air filtering capability as well. All such filters are accessible from inside the enclosure, and may be monitored electronically for automatic signaling to the shooter who will be required to activate a control system before assuming an active position at the shooter's station.

The rear wall 16 of the enclosure includes a pressurized plenum chamber that directs ventilating/filtered air forwardly toward the front/open end 32 of the enclosure. Thus, air contaminated by the shooter's weapon fired at the shooter's station 30 is directed forwardly as suggested by the arrows 28, 28 in FIG. 2. This contaminated air is drawn through filters in the cabinet 34. A four-stage filtration system is provided, comprising: a pre-filter, ring filter, charcoal filter, and a HEPA filter, all arranged in series. Air is re-circulated at a rate of at least 6 times per minute. This rate of air flow coupled with the slight negative pressure created by exhausting some contaminated air to atmosphere through the ceiling vent 36, assures that the shooter does not suffer any ill effect from the enclosed space at the shooter's station.

In addition to placement of the inlet, or inlets, to the collection chamber 34 close to the front end of the enclosure, another important feature of the present invention is placement of a self contained air curtain generating device 40 on the wall 12 opposite the vent unit inlet, or inlets, in the wall 10 associated with the air recirculation ductwork. FIG. 2 shows this air curtain generating unit 40 in a corner defined by one of several strategically placed baffles, 42, 42 provided on the inside of side walls 10 and 12. Whereas conventional air moving blowers and air filtering apparatus are contained inside the recirculation and filtering system, the self contained air curtain generating device 40 simply draws in ambient air from inside the enclosure and directs an air curtain of high velocity air from one side wall 12 toward the opposite side wall 10, and more particularly in a direction such that this air reaches the vent inlet where the filters are located, cabinet 34.

The above-described configuration assures that no appreciable quantity of contaminated air escapes from the enclosure, and that the majority of this air is either re-circulated through the filters provided at 34, or exhausted to the outside world through the unit 36. Filters are provided in unit 36 as well, and monitored in the same way as those provided for the re-circulated air by a control system to be described.

The baffles 42,42 include portions that hang downwardly from the inside of top wall 14, and such baffles serve to slow the flow of air downstream along these walls and along the inside of top wall 14. This slowing of such air-flow, in the relevant regions inside the enclosure, increases slightly the air pressure in these regions, that is immediately upstream of these baffles. Consequently, by placing the air inlet vents behind these baffles 42, 42 greater efficiencies in the air flow into the blowers can be achieved.

A further function for these baffles 42, 42 is simply to reduce the noise generated by the shooter when firing his weapon at the shooter's table/station 30. The side walls and roof are of laminated pressboard with sound insulating core, and are vinyl coated. Quilted fiberglass sound absorbing blankets, about 2″ thick, are hung on the inside of the side walls and also mounted to the ceiling of the enclosure. Muzzle blast noise is reduced by 75%, to a level less than that inside an airport terminal for example.

While the baffles 42, 42 are so placed as to slow the flow of air in these regions, air dams 44, 44 are placed immediately downstream of the shooter's station to accelerate air flowing over these dams, and heighten the rate at which contaminates are drawn downstream, beyond that achieved by the air flow pattern from the grille and grid structure described previously. These dams 44 create a cross sectional area reduction in the enclosure causing an increase in air velocity just downstream of the shooter's station, assuring him, or her, of adequately filtered air when rapid firing of his weapon might otherwise be expected to create greater exposure to noxious gasses and other products of combustion at the shooter's station. Preferably, the right side wall 12 dam 44 is located rearwardly relative the dam on the left side wall 10.

The enclosure described herein is designed for use in a residence, or other building that has occupants who should be protected from harm during the firing of a weapon, from inside the enclosure, to a target located outside the enclosure. Therefore, a perimeter alarm system should be installed in the building where the enclosure is located. Such an alarm system has motion detectors or other sensing devices strategically mounted at access points to the space utilized for the enclosure and associated target area. These detector devices must be activated before firing a weapon, and indicators inside the enclosure are provided to alert the shooter when these devices are inactive. Once the system is activated, the shooter will be alerted to a tripped detector device by automatic activation of a light or other warning device inside the enclosure. Preferably a flashing red or yellow light is energized in response to a detector device being tripped. Another warning device such as a klaxon horn may also be activated to warn both the intruder and the shooter when electrical power has been turned on inside the enclosure and someone has tripped one of the detection devices in the area.

A further feature of the shooter's enclosure is provision, inside the enclosure, for warning the shooter when the air filters require maintenance or replacement. When the design air flow rate (75-100 feet per minute) drops below this range, a warning device alerts the shooter to the need for checking these filters and replacing and/or cleaning them in accordance with recommended periodic maintenance requirements. It is also recommended that a rug be placed on the floor inside the enclosure to serve two purposes, first to aid in noise reduction during firing inside the enclosure, and second, to entrain particles that are not carried away by the ventilation and filtration system. It is also recommended that this rug be cleaned periodically, preferably by an industrial style high efficiency HEPA vacuum capable of capturing particles of 0.03 microns with 99.97% efficiency.

Claims

1. An enclosure for use by a shooter at a shooter's station defined therein, the shooter able to fire from said station at a target located outside the enclosure, said enclosure comprising;

a generally rectangular walled structure having one and another side walls and a top wall, and including front and back ends, the front end being substantially open, said back end defining a pressurized air plenum creating a generally uniform air flow from back to front of said enclosure,

an air circulating and filtration system supplying pressurized air to said plenum, and including at least one air-ventilating unit accessible from inside said enclosure, and

an air curtain creating unit provided oppositely to at least one said air ventilating unit inside said front end of said enclosure to provide a curtain of air between said enclosure side walls adjacent to said open front end thereof.

2. The enclosure of claim 1 wherein said pressurized air plenum comprises a grid for receiving air from said air ventilating unit discharging that air so received in a generally uniform flow pattern from said back end toward said open front end, and between said side walls of said enclosure. Said grid including at least one foraminous sheet therein.

3. The enclosure of claim 2 further including air flow diverting dams provided on said side walls inside said enclosure to accelerate the airflow downstream of said shooter's station.

4. The enclosure of claim 3 further including an auxiliary air ventilating unit in said top wall adjacent said open front end of said enclosure for reducing the ambient air pressure inside said enclosure by exhausting air to a location remote from said enclosure, said auxiliary unit operating independently of said air circulating and filtration system.

5. The enclosure of claim 1 wherein said air curtain unit has an inlet side drawing air from inside said enclosure adjacent one of said side walls, opposite said air ventilating unit, and said air curtain unit directing the air curtain laterally and generally normal to said one side wall, said air ventilating unit drawing air from inside said enclosure adjacent the other of said enclosure side walls and generally oppositely from said air curtain discharge direction.