Rotatable helmet mount

A helmet mount for a night vision device is provided having means to attached to headgear, such as a helmet, wherein the mount is rotatable between a use position and a stowed position about an axis that is substantially parallel to the attachment means. In one embodiment, a position adjustment assembly comprises a rotary plate, a helmet block rotationally coupled to the rotary plate and a spring-biased ball and socket system located between the helmet bock and rotary plate. In another embodiment, a tilt adjustment assembly may include a gear system wherein rotation of a lever produces rotation of a night vision device relative to a user's eyes.

FIELD OF THE INVENTION

This invention relates generally to mounting assemblies for night vision devices, and more particularly to a rotatable helmet mount for night vision devices that rotates a night vision device between a use position and a stowed position and preferably includes vertical adjustment, tilt adjustment, and focal adjustment. The invention may also include automatic shutdown assemblies.

BACKGROUND OF THE INVENTION

Night vision devices are commonly used by military personnel for conducting operations in low light or night conditions. The night vision devices utilized by the military typically include image intensifier tubes and associated optics that convert infrared and near infrared light into viewable images. A common night vision device currently being used in the U.S. Army is the PVS7 night vision device, manufactured by ITT Corporation in Roanoke, Va.

Assemblies for mounting night vision devices to a helmet are well known in the art. These mounting assemblies allow a user's hands to remain free while viewing a scene through the night vision device. Prior art mounting assemblies typically include one or more of the following features: positional adjustment of the night vision device between a use and stowed position; tilt angle adjustment of the night vision device relative to the user's eyes; focal adjustment of the location of the night vision device relative to the user's eyes; and automatic shutdown of the night vision device when not in the use position.

A known mounting assembly for night vision devices encompasses a flip-up helmet mount that attempts to provide all of the features identified above. See, for example, U.S. Pat. Nos. 5,914,816 to Soto et at., 6,457,179 to Prendergast and 6,472,776 to Soto et al. which are incorporated herein by reference. However, when the previously disclosed mounting assemblies are flipped up, the night vision device rests a few inches away from the front edge of the helmet. This places the center of gravity of the night vision device/helmet mount assembly further forward than simply the helmet alone and may place an undue strain on the user's neck. It is desirable to have a night vision mounting assembly that accomplishes the features identified above, yet places less strain on the user's neck.

Known flip-up helmet mounts also require the presence of an automatic shutdown assembly. This feature is desired because a phosphor yellow/green light emitted from the night vision device would be visible to possibly hostile personnel in front of the operator if the device was not turned off when stowed. However, should the automatic shutdown assembly fail to operate for any reason, the user may be placed in a potentially dangerous situation.

These and other problems could exist with the flip-up helmet mounts for night vision devices disclosed in the prior art. Consequently, a need exists for a different approach to a helmet mount.

SUMMARY

The present invention provides a different approach to a helmet mount for night vision devices. More particularly, the helmet mount according to the present invention is designed to rotate so that, in the stowed position, the center of gravity of the night vision device/helmet assembly is more directly over the center of the user's head, reducing strain on the user's neck. In addition, the rotatable helmet mount is designed so that the eyepieces which may emit a phosphor yellow/green light are flush with the helmet and the light is not particularly visible when the device is in a stowed position.

DETAILED DESCRIPTION

Referring now toFIG. 1, a presently preferred embodiment of a rotatable helmet mount10according to the present invention is shown. The rotatable helmet mount10is shown in use with a standard U.S. Army Kevlar composite helmet12. A night vision device14is secured to the helmet12by use of the rotatable helmet mount10. The night vision device14shown inFIG. 1is a device that includes a single objective lens16, a housing18and a pair of eye pieces20. To use the night vision device14, the operator places the device into the position depicted in FIG.1and looks into the eye pieces20to see an enhanced image representative of the low-level light from a night scene which has entered the objective lens.

The rotatable helmet mount10may be secured to the helmet12in any of the ways well known in the art.FIG. 1shows the rotatable helmet mount secured to the helmet by means of a shroud plate22. The shroud plate22is described in U.S. patent application Ser. No. 10/389,648, Filed on Mar. 13, 2003, entitled “Shroud Plate”), which is incorporated herein by reference. The shroud plate22comprises a shell, an insert, a lock and a release button. A lock plate may be inserted into the insert where it will be secured in place by the lock and may be released by using the release button. The rotatable helmet mount10may also be secured to the helmet12by the use of a quick release mechanism which may be attached to the helmet by a strap or with fasteners.

The night vision device may be removably attached to the rotatable helmet mount. In an exemplary embodiment, the night vision device is removably secured to a socket assembly152, on the helmet mount, comprising a housing154(FIG.13). The housing154as shown inFIG. 13has a receiving area161formed by a tapered recess located centrally across the width of the housing154. The receiving area is configured to receive a portion of a night vision device, such as a goggle horn. Substantially centered within the receiving area161is a dugout163which may house part of a release assembly164. In one embodiment, the release assembly164may comprise a detent165, a rod167, a protrusion169, a spring171and a knob180. The detent165serves to securely connect a night vision device to the socket152and thereby to the helmet mount10. Additionally, the housing154may contain additional dugouts162which are created to minimize the weight of the socket assembly152but do not jeopardize its structural integrity.

In one embodiment, the detent165may have a channel166running about half of its length and bisecting its width as shown in FIG.15. The exact shape of the detent165is not critical, but the detent should be shaped such that it secures a night vision device to the mount10. As shown inFIGS. 14a-14b,in one exemplary embodiment the detent165may have a bowtie shape when viewed from the side, rectangular when viewed from the top, having a channel end157and an operating end158. A rod167may run perpendicularly through the detent165and the channel166. Attached to the rod167and extending outwardly at a right angle to the longitudinal axis of the rod may be a protrusion169which is adapted to fit within the channel166. Attached to and encircling an end of the rod167may be a spring171and a knob180. In one configuration, when the socket assembly152is assembled, the rod167is passed through openings in the housing154and the detent165is aligned within the dugout163. The walls of the dugout163prevent lateral movement of the detent165while the protrusion169prevents lateral movement of the rod167. Further, a spring (not shown) in the dugout163biases the detent165so that its operating end158is elevated above the surface of the goggle horn receiving area161.

As shown inFIGS. 7a-7c,the night vision device may include a goggle horn315that is adapted to be received in the socket assembly152of the helmet mount. The goggle horn315may be attached to the night vision device314as shown inFIG. 7cby a screw or bolt which is inserted through a hole370. The hole370may be two-tiered or have a counterbore such that the head of a screw or bolt inserted into the hole is flush with a receiving area372. In an exemplary embodiment, the goggle horn315may be wedge-shaped such that is has a wider front area that tapers to a smaller back area so as to fit into the receiving area161on the lower socket154of the socket assembly152of FIG.13. The goggle horn315further may have tapered sidewalls which correspond to the tapered sidewalls of the goggle horn receiving area161and further ensure a secure fit between the night vision device314and the mount10.

In a preferred embodiment, the goggle horn315has a receiving area372which is indented below the top surface of the goggle horn and which is adapted to receive the detent165. As the socket assembly152is introduced to the goggle horn315, the socket assembly slides over the tapered front edge374of the goggle horn. As the goggle horn315slides further along the receiving area161, the goggle horn315overcomes the spring-biased detent165until the detent is received by the receiving area. The socket assembly154is prevented from further movement by tapered inner walls of the goggle horn315that secure the detent165to the receiving area372.

In an exemplary embodiment, in order to release the socket assembly152from the goggle horn315, a user may turn the release knob180. The release knob180may be spring-biased so as to return to its unrotated position after it is rotated. The release knob180is rotationally coupled to the rod167and thus also to the protrusion169. When the knob180is initially rotated a certain number of degrees, the protrusion passes through the open channel166in the detent165. In other words, even though the knob180is rotated, the rotation will not cause the protrusion169to act on the detent165and thus, the initial rotation will not act to release the night vision device314from the helmet mount10. This “free rotation” is built into the socket assembly152as a safety device to prevent the accidental release of the night vision device314from the helmet mount10if, for instance, the user brushes against tree branches or other obstacles during a maneuver. The amount of free rotation is not critical, but is preferably between about 60°-120°. If the knob180is rotated past the critical number of degrees of free rotation, the protrusion169will engage the detent165. When the protrusion169engages the detent165, the detent will rotate as the knob180is rotated, forcing the detent to overcome the spring bias and allowing the elevated back surface of the detent165to detach from the receiving area372of the goggle horn315.

In an alternate embodiment, as shown inFIGS. 7a-8b,a night vision device314is removably secured into a socket assembly352. The socket assembly352as shown inFIGS. 8a-8bhas an upper socket353and a lower socket354coupled to the upper socket353by screws355. The upper socket353has a contacting surface359. The lower surface354has a contacting surface357that abuts contacting surface359when the upper socket353and lower socket354are coupled.

As described above and further shown inFIG. 8b,the lower socket354has a goggle horn receiving area361similar to the socket assembly152of FIG.13. In addition, the lower socket354has cylindrical holes356that extend from the bottom of socket354through contacting surface357. Threaded holes356are provided for receipt of screws355. In a preferred embodiment, there are four holes, with one hole in each corner of the lower socket354.

In this embodiment, the detent365may have a channel centrally located along its width, dividing the detent365into two halves and adapted to hold a rod367. The rod367may be fitted into two holes in either side wall of the dugout363and serves as a surface on which the detent365may pivot. The detent365has a front surface which may slope toward the front of the socket assembly352. The detent365further may have a ramped back surface that hooks into an indented receiving area372on the goggle horn315on the night vision device314for secure assembly. The back surface of the detent365may be biased above the top of the dugout363by a spring356′ located underneath the top half of the detent365. This allows the detent365to protrude into receiving area372of the goggle horn315(FIG. 7a) and secure it to the socket354.

As shown inFIG. 16, a release knob380is rotationally coupled to a cam (not shown) located above the front half of detent365. When the cam is rotated, it overcomes spring-biased detent365to disengage the elevated back surface of the detent365from receiving area372of goggle horn315. In a preferred embodiment, the user must rotate knob380120° in order to disengage detent365. In this embodiment, the first 90° of rotation are redundant, i.e. they have no effect on detent365, while the last 30° cause the detent to move. This insures that inadvertent movement of the knob380will not detach the night vision device from the helmet. Once the detent365is disengaged from the goggle horn315, a user may slide the night vision device314out of the socket354.

In yet another alternate embodiment as shown inFIG. 18, a spring-biased knob380may be connected to a wedge-shaped cam. In order to disengage the detent365from the goggle horn315, the user may rotate and then push in the knob380so as to drive the wedge underneath the detent365. The wedge will then cause the front portion of the detent365to rise and the back portion to lower, allowing removal of the goggle horn315. The requirement for two distinct motions for disengagement provides for further protection against inadvertent disengagement should such further protection be desired.

POSITION ADJUSTMENT

InFIG. 1, the night vision device14is positioned in front of the operator's eyes so that the operator may look through the eye pieces20of the night vision device14. InFIG. 17, the night vision device14is positioned completely above the line of sight of the operator, to permit normal, unobstructed vision, unaided by the night vision device14. ViewingFIG. 1in combination withFIG. 17, the rotatable helmet mount10is rotatable about a point in front of the headgear and above the line of sight of the user in a circular motion within a plane which is generally tangential to a point of attachment of the night vision device14and the helmet12to allow the operator to rotate the night vision device14in either a clockwise or counter-clockwise direction between the use position and the stowed position.

In order to enable the operator to adjust the position of the night vision device14, the night vision device14is rotationally coupled with helmet block38. As shown inFIGS. 2 and 3, the rotatable helmet mount10comprises a rotary plate30which may be secured to a lock plate32or any other device which enables the rotatable helmet mount to attach to a helmet. In an exemplary embodiment, the rotary plate30is attached to the lock plate32by the screws34. The screws34may be inserted through holes in the lock plate32and threaded into holes36in the rotary plate30. The rotary plate30may also be attached to lock plate32by any other suitable means, such as by rivets or bolts. In an alternate embodiment, the face of the rotary plate30may be separated from a helmet block38by an O-ring (not shown). Rotary plate30may be attached to helmet block38by a screw42which is inserted through a hole39in the center of the rotary plate30and threaded into a hole41in the helmet block38. As shown inFIG. 6, the screw42may comprise a main cylindrical body having a threaded tip44and having a smooth middle section46. The smooth middle section46serves as an axle on which the rotary plate30may rotate. The rotary plate30may also be attached to the helmet block38by any other suitable means.

In an exemplary embodiment, the helmet block38may comprise a rear face slanted at an angle which corresponds to the front of the helmet so as to allow the night vision device to remain substantially parallel to the user's line of sight when the night vision device14is in the use position as shown in FIG.1.

In a further exemplary embodiment of the present invention, the rotary plate30may rotate on at least one ball bearing. In a preferred embodiment as shown inFIG. 5, the rotary plate may rotate on two ball bearings50. Ball bearings may reside in sockets52in the surface of rotary plate. As will be obvious to those skilled in the art, the present invention is not limited to two ball bearings, but may have any number of ball bearings suitable for rotation.

In a further preferred embodiment, a user must overcome a bias in order to rotate the helmet mount10. In order to achieve such bias, the helmet block38may contain cavities54shaped to receive a ball bearing50, as shown in FIG.4. The cavities54may contain a spring56on which the ball bearing50may rest until enough lateral force is applied to the helmet mount10to displace the ball bearing50from the cavity54. The depth of the cavity54may vary depending on the amount of resistance desired to rotate helmet mount10.

In an alternate embodiment, the helmet block38may be adapted to encompass a rotary plate130. In this embodiment, the rotary plate130may rotate on at least one ball bearing. In a preferred embodiment, the rotary plate may rotate on two ball bearings. As shown inFIG. 19, the rotary plate may contain at least one socket on its perimeter which is oriented in the same plane at the face of the rotary plate. The socket may contain a spring on which a ball bearing may rest until enough lateral force is applied to the helmet mount to displace the ball bearing from the socket148.

It will be obvious to one skilled in the art that the force required to adjust the night vision device from the use to the stowed position will depend on a number of factors including the number of spring-biased cavities, the size of the spring-biased cavities, the strength of the springs and the depth of the cavity, among other things.

TILT ADJUSTMENT

In addition to allowing for adjustment of the position of the night vision device14, the rotatable helmet mount10also allows for adjustment of the tilt of the night vision device relative to the user's eyes. In a presently preferred embodiment shown inFIG. 9, a gear system is provided to permit tilt angle adjustment of a housing402of a tilt mechanism400. In an exemplary embodiment, the tilt adjustment mechanism400comprises a lever430rotatably coupled to an upper gear432by any suitable means, such as a screw or rivet. The tilt adjustment mechanism400further comprises a lower gear434attached to a support column403. The housing402may be rotationally coupled to the column403by a screw436or any other suitable means, such as a rivet or pin.

To adjust the tilt angle of the housing402, a user may rotate the lever430causing the upper gear432to simultaneously rotate and allowing cogs on the upper gear432to interlock with cogs on the lower gear434. Since the lower gear434is held in place by support column403, the housing402will rotate around the screw436as a result of rotation of the upper gear432. The amount of rotation of the housing402will be determined by the amount of rotation applied to the lever430by the user.

An advantage of the gear operated tilt adjustment mechanism is that it allows for one-handed tilt adjustment of the night vision device. As can be appreciated fromFIG. 9, tilt adjustment can be accomplished by using only one hand to turn the lever430. The design of the gear operated tilt adjustment mechanism allows for real-time adjustment of the tilt angle of the night vision device. Moreover, the gear operated tilt adjustment mechanism allows for substantially infinite adjustment of the tilt angle within a predetermined range, rather than limiting the tilt angle adjustment to one of a plurality of predetermined levels.

FOCAL ADJUSTMENT

The rotatable helmet mount10also allows for focal adjustment of the location of the night vision device relative to the user's eyes. As described above, the night vision device is coupled with the socket assembly152. As shown inFIG. 10b,the receiving surface406of the housing402is adapted to receive the socket assembly152. In a preferred embodiment, the receiving surface406may be dovetailed to correspond to the dovetail shape of the socket assembly152. The user may slide the socket assembly152along the receiving surface406to adjust the position of the night vision device14relative to the user's eyes. As shown inFIGS. 9 and 10b,the front end of the receiving surface406may have a protrusion404extending from the surface to prevent the socket assembly152from sliding off the housing402.

FIGS. 11a-11cshow the top half353of the socket assembly352, having a top surface409and a bottom surface411. As shown inFIG. 11a,in an exemplary embodiment, the top surface409may contain a cavity416. The cavity416is adapted to receive the protrusion404extending from the underside of housing402to prevent the housing402from sliding off the end of the socket353. Further, the socket353may comprise a focal adjustment assembly. The focal adjustment assembly may comprise a stop414biased by springs410and held in place by a rod420connected to a shaft412. The stop414may rest so that its outer edge protrudes slightly past the edge of the top surface409when the housing402is not attached. The stop414may be made from a somewhat flexible material and in a preferred embodiment, may be made from nylon 6/6. The focal adjustment mechanism may further comprise a lever422connected to a cam (not shown) by a screw424or other appropriate means of connection. The lever is biased by a spring (not shown) to be in a “hold” position. In order to attach a helmet mount, the user may turn lever422to a “release” position. When the lever422is turned by a user, the cam rotates and causes the shaft412to move slightly toward springs410. Movement of the shaft412, with rod420attached, moves the stop414so that the outer edge of the stop414is flush with an edge of the top surface409and no longer protrudes. Once the stop414is flush with the top surface409, the user may slide the receiving surface of the housing402onto the top surface409. After the housing402has been attached to the socket353, the user may release the lever422. The spring will bias the lever422to return to its hold position, causing the cam to release the shaft412and allowing the springs410to exert a lateral force on the stop414. The stop414will in turn exert a lateral force on receiving the surface406holding the housing402in place.

In order to change the position of the housing402with respect to the socket353, a user may rotate the lever422to the release position and slide the socket353to the desired position.

An advantage of the focal adjustment assembly provided is that it allows for one-handed focal adjustment of the night vision device. As can be appreciated fromFIGS. 11a-11c,focal adjustment can be accomplished by using only one hand to turn the lever422and slide the socket353to the desired position.

VERTICAL ADJUSTMENT

The rotatable helmet mount10further allows for vertical adjustment of the night vision device14relative to the user's eyes. In a presently preferred embodiment of the present invention as shown inFIG. 2, the vertical adjustment mechanism59may comprise a housing58attached to the helmet block38. The housing58may be attached by screws, rivets, pins or by any other suitable means for attachment. Inner surfaces of the housing58and the helmet block38may be shaped to form a channel57as shown more clearly inFIG. 12a.A screw64may be used to move the mount assembly10vertically. The screw64may be inserted through a hole in the top of housing58and may extend through the channel57. A flanged insert60with a smooth inner surface may be inserted between the screw64and the housing58and may serve to allow the screw64to rotate freely. The screw64may be attached to the support column403by inserting the screw64into a threaded member69(seeFIG. 10a). The threaded member69may be attached to the support column403by placing the member into a cavity70that may be centrally located on the surface of column403. The threaded member69may be machined to have a generally rounded body and a generally square base. Through the center of the member69may be a threaded hole adapted to receive the screw64. The cavity70may be sized to receive and hold the member69as shown inFIG. 10b.

In order to adjust the vertical position of the night vision device, a user may turn a knob61which will turn threads of the screw64. This will result in the helmet mount moving either up or down, depending on the direction of rotation of the screw64. In a preferred embodiment, so as not to allow the user to completely detach the support column403from the screw64, there may be a protrusion on the screw which prevents the screw from further rotation once it has reached a predetermined location.

While various embodiments of this invention have been shown and described, it would be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concept herein. For example, although the tilt and focal adjustment assemblies have been illustrated on one side of the rotatable helmet mount, is should be realized that the assemblies could easily be located on either side of the rotatable helmet mount. In other words, the rotatable helmet mount could be designed for one-handed operation by either the right or left hand of the user. It is, therefore, understood that within the scope of the appended claims, this invention may be practiced otherwise than as specifically described.