Visor-latching Device

Abstract

A device which is particularly adapted for holding a movable visor on a headgear in a predetermined position which includes a friction surface mounted in a stationary position on the headgear and a friction clutch or latch mounted on and movable with the visor, the friction clutch including a pair of friction pawls spring biased on opposite directions and deflectable from engagement with the friction surface only in a direction acting against the spring bias so that acting together the friction pawls prevent linear motion in either direction and when one friction pawl is deflected out of contact with the friction surface motion in one direction is possible. A movable clutch finger is provided to deflect the selected friction pawl.

Description

The present invention provides a clutch or latch device which is particularly suitable for use with movable visors on headgear pieces. The clutch device of this invention is operable under adverse conditions. The ready accessibility of the actuating member to the wearer of the headgear permits the clutch to be operated by a heavily gloved hand with speed and accuracy. When the clutch device is affixed to the movable visor, it also serves as a handle to move the visor from one desired position to another. The arrangement of the operative elements of the friction clutch is such that the clutch operates when the actuating member is pushed in the direction in which it is desired to move the visor. The wearer of the headgear needs to make only one continuous motion in the desired direction to accomplish both the disengaging of the clutch and the movement of the visor.

The convenience and efficient utility of this clutch device are also very useful in many other structures where two elements of the structure are movable relative to one another but must be releasably held in fixed relationship to one another at various positions. The clutch device of this invention is equally effective at any position along the friction surface.

When a dual-visored helmet is to be equipped with clutches of this invention, it is convenient to provide one clutch on each side of the helmet with the clutch on one side being operatively associated with the outer visor and the clutch on the other side being operatively associated with the inner visor.

In the drawing there is illustrated:

FIG. 1 is a side elevation of a dual visor helmet with a clutch or latch device operatively associated with each visor;

FIG. 2 is a side elevation partly in phantom of the dual visor helmet shown in FIG. 1;

FIG. 3 is a perspective cutaway view of a clutch device;

FIG. 4 is a perspective broken view of a further embodiment of a clutch device of this invention;

FIG. 5 is a side elevational view in cross section of an embodiment of a clutch device of this invention;

FIG. 6 is a cross-sectional view taken along line 6--6 in FIG. 5;

FIG. 7 is a side elevation sectional view taken along line 7--7 in FIG. 5;

FIG. 8 is a view similar to FIG. 7 showing the clutch device in one actuated position;

FIG. 9 is a view similar to FIG. 7 showing the clutch device in a second actuated position;

FIG. 10 is a perspective cutaway view of a further embodiment of a clutch of this invention;

FIG. 11 is a sectional view taken along line 11--11 in FIG. 10;

FIG. 12 is a perspective cutaway view of a further embodiment of a clutch device of this invention;

FIG. 13 is a cross-sectional view taken along line 13--13 in FIG. 12;

FIG. 14 is a perspective cutaway view of a further embodiment of a clutch device of this invention;

FIG. 15 is a front elevation sectional view of the clutch device illustrated in FIG. 14;

FIG. 16 is a front elevation sectional view of a further embodiment of a clutch device of this invention;

FIG. 17 is a cross-sectional side elevation view of a further embodiment of a clutch device of this invention;

FIG. 18 is a perspective cutaway view of the clutch device illustrated in FIG. 17; and

FIG. 19 is a perspective view in phantom illustrating an additional embodiment of a clutch device of this invention.

Referring particularly to the drawings, there is illustrated a helmet 10 which is provided with a generally spherical curved crown 12 and curved lobes 14 depending from the lower edge of the crown at diametrically opposed sides thereof. When the helmet is placed on the head of a wearer, lobes 14 cover and protect the sides of the head and ears of the wearer. The front opening of the helmet is defined between the forward downwardly presented edge 16 of crown 12 and the forwardly presented edges of the side lobes 14. The face of the wearer is exposed through the opening thus defined. In a typical helmet of the kind illustrated in the drawings, the forward edge of the crown 16 extends across the forehead of the wearer approximately at the level of the eyebrows.

In the visor construction represented in the drawings, a visor attachment 18 is secured to the helmet 10. The visor construction includes a visor housing 20, which is curved in both the horizontal and vertical planes to embrace the forward portion of the helmet crown 12 in the region directly above the forward crown edge 16. The housing has a forwardly presented wall 22 along the upper edge of which is a rearwardly directed flange 24. Flange 24 seats against the outer surface of the helmet crown 12 to space the upper edge of the forwardly presented housing wall 22 from the crown.

Indicated at 30 and 32 in phantom in FIG. 2 and in FIG. 1 are a pair of transparent visors or lenses movably mounted in a spaced-apart superimposed relationship. Each transparent visor lens 30 and 32 is curved horizontally and vertically to match the curvature of visor housing 20. The visor housing wall 22 and the visor lenses 30 and 32 are circularly curved in each vertical plane parallel to the fore and aft plane of the symmetry of the helmet 10, about a common axis extending normally to said planes. The two downwardly and rearwardly extending edge ends of each visor lens 30 and 32 at the sides 14 of the helmet 10 are also circularly curved about a common axis.

Visor tracks 26 and 28 are mounted at the respective temple areas of helmet 10 and are adapted to cooperate with extensions of visor lenses 30 and 32 to carry these lenses as they move from retracted to extended positions. The visor lenses 30 and 32 are provided with respective visor lens holders 34 and 36. These lens holders 34 and 36 serve as extensions of the respective visor lenses 30 and 32. The visor lens holders are mounted at the downwardly and rearwardly extending edge ends of the visor lenses.

A friction surface 38, see, for example, FIG. 3, is provided on an outwardly projecting ledge of visor track 26. A further embodiment of a friction surface 40 is provided on an arcuate rearwardly presented side of visor housing 20, see, for example, FIG. 4. The respective friction surfaces 38 and 40 are adapted to cooperate with a clutch device of this invention.

The clutch or latch device, indicated generally at 42 and illustrated particularly in FIGS. 3 and 5 through 9, includes a clutch or latch support 44 which is integral with lens holder 34. Clutch device 42 includes a housing 46 mounted on clutch support 44 and a piston 48 slidably received in 46 for axial movement therein. Clutch or latch fingers 50 and 51 are linked together by piston 48 and extend outwardly in the same plane from piston 48. Friction pawl 52 is pivotally mounted on clutch support 44 for rotation in a plane parallel to the axis of piston 48 and normal to the axis of clutch finger 50. Friction pawl 52 is provided with an outer end tip 54 which is adapted to be normally positioned in frictional engagement with surface 38. Friction pawl 56 is pivotally mounted on clutch support 44 for rotation in the same plane as friction pawl 52. The outer end tip 58 of friction pawl 56 is adapted to be normally frictionally engaged with friction surface 38. A preload torsion spring 60 is mounted between friction pawls 52 and 56 on a spring retainer pin 62. The arms of preload torsion spring 60 are positioned so that they act on the respective inner opposed sides 64 and 66 of friction pawls 52 and 56, thus tending to urge the outer end tips of friction pawls 52 and 56 outwardly from one another. Clutch fingers 50 and 51 are disposed respectively adjacent the outer opposed sides 68 and 70 of respective friction pawls 52 and 56.

In operation the clutch device, indicated generally at 42, is positioned so that friction pawls 52 and 56 are positioned adjacent friction surface 38 with their respective outer end tips 54 and 58 in frictional engagement with friction surface 38. The friction pawls 52 and 56 are mounted adjacent to friction surface 38 in such a manner that the distance from the pivot point of the pawls to the surface 38 is slightly less than the length of the friction pawl projecting from the pivot point toward friction surface 38. The pawls are slightly deflected towards one another and against the reaction of preload torsion springs 60. The friction pawls 52 and 56 are thus located slightly over center from their pivot points towards one another so that the force of torsion spring 60 tends to drive the outer end tips 54 and 58, respectively, of the pawls into locking frictional engagement with friction surface 38. Friction pawl 52 resists relative movement between clutch support 44 and the friction surface 38 in a direction such that a point on friction surface 38 would move from friction pawl 56 toward friction pawl 52. Friction pawl 56 resists relative movement between friction surface 38 and clutch support 44, wherein a point on friction surface 38 moves from friction pawl 52 towards friction pawl 56. So long as both friction pawls 52 and 56 are in frictional locking engagement with friction surface 38, relative movement between friction surface 38 and clutch support 44 is prevented. Axial movement of slidably mounted piston 48 carries clutch fingers 50 and 51 with it and deflects one of the friction pawls 52 or 56. The movement of piston 48 toward the outer opposed side 68 of pawl 52 causes clutch finger 50 to deflect pawl 52 away from friction surface 38 and toward friction pawl 56. With the outer end tip 54 of friction pawl 52 released from friction surface 38, clutch support 44 is free to move relative to friction surface 38 in such a direction that a point on surface 38 moves from friction pawl 56 towards deflected friction pawl 52, as illustrated particularly in FIG. 8. The outer end tip 58 of friction pawl 56 slides along friction surface 38 as long as it continues to move in this direction. Friction pawl 56 will enter into locking frictional engagement with friction surface 38 to prevent relative motion in the other direction. When it is desired to move clutch support 44 and friction surface 38 relative to one another in the opposite direction, piston 48 is moved axially towards the outer opposed side 70 of friction pawl 56 and clutch finger 51 deflects friction pawl 56 against the reaction of preload torsion spring 60 towards friction pawl 52, thus disengaging outer end tip 58 from locking frictional engagement with friction surface 38. Relative movement between clutch support 44 and friction surface 38 is now possible in a direction such that a point on friction surface 38 moves from friction pawl 52 toward friction pawl 56, as illustrated particularly in FIG. 9. When friction surface 38 is stationary, the force applied to the piston 48 to release a respective friction pawl is applied in the same direction in which clutch support 44 is free to move after a friction pawl has been released from locking engagement with friction surface 38. When the clutch device is used in connection with a visor on a helmet, the wearer of the helmet need only make one continuous motion in the direction in which it is desired to move the visor lens to accomplish both release of the clutch and movement of the lens.

The clutch device, indicated generally at 72 and illustrated particularly in FIGS. 10 and 11, includes a clutch support 74 which is integral with a lens holder and forms an extension of a visor lens. A housing 76 is mounted on clutch support 74. A piston 78 is slidably mounted in housing 76 for axially movement. A clutch finger 80 is linked to and extends outwardly from piston 78. Friction pawl 82 is mounted to clutch support 74 on pawl pivot pin 84. Friction pawl 82 has an inner opposed side 86 and an outer opposed side 88 and an outer end tip 90. Friction pawl 92 is mounted for pivotal movement on clutch support 74 by means of pawl pivot pin 94. Friction pawl 92 is provided with an inner opposed side 96, an outer opposed side 98, and an outer end tip 100. Outer end tips 90 and 100, respectively, are adapted to be normally positioned in frictional locking engagement with frictional surface 38. A preload torsion spring 102 is mounted between friction pawls 82 and 92 on spring retainer pin 104. Preload torsion spring 102 acts against the outer opposed sides 88 and 94, respectively, of friction pawls 82 and 92 and urges these friction pawls inwardly towards one another. Clutch finger 80 is disposed between friction pawls 82 and 92 and is in contact with respective inner opposed sides 86 and 96. The distance between friction surface 38 and the pivot points 84 and 94, respectively, of friction pawls 82 and 92 is adjusted so that it is slightly less than the length of the friction pawls extending from their respective pivot points to the friction surface 38. The pawls are mounted so that the action of the preload torsion spring 102 wedges the friction pawls inwardly towards one another against surface 38. The frictional locking engagement of pawl 82 with surface 38 is such that pawl 82 prevents relative movement between clutch support 74 and surface 38, wherein a point on surface 38 moves from pawl 82 towards pawl 92. Pawl 92 frictionally engages with friction surface 38 to prevent the movement of a point on surface 38 from pawl 92 towards pawl 82. Clutch finger 80 is positioned between friction pawls 82 and 92 and is in contact with the respective inner opposed sides 86 and 96. The movement of clutch finger 80 towards pawl 92 and away from pawl 82 will result in the disengagement of frictional pawl 92 from frictional locking engagement with friction surface 38. This movement of clutch finger 80 is effected by moving piston 78 toward friction pawl 92. With friction pawl 92 disengaged through the action of clutch finger 80, relative movement between friction surface 38 and clutch support 74 is possible in such a direction that a point on friction surface 38 moves from friction pawl 92 towards friction pawl 82.

In the embodiment, illustrated particularly in FIGS. 12 and 13, a clutch device 106 is provided with clutch support 108 and a movable housing 110 slidably mounted on clutch support 108. Clutch finger 112 is movable with housing 110. Friction pawl 114 is pivotally mounted on pawl pivot pin 116. Pawl pivot pin 116 is journaled in clutch support 108. Friction pawl 114 is provided with inner opposed side 118, outer opposed side 120, and outer end tip 122. Friction pawl 124 is pivotally mounted on pawl pivot pin 126 and has inner opposed side 128, outer opposed side 130, and outer end tip 132. A preload torsion spring 134 is mounted between friction pawls 114 and 124 on spring retainer pin 136. Spring retainer pin 136 is mounted in clutch support 108. Preload torsion spring 134 bears against the outer opposed sides 120 and 130, respectively, of friction pawls 114 and 124 so as to bias these friction pawls inwardly toward one another. The coaction between the friction pawls and a friction surface, not shown, is substantially the same as that described hereinabove, particularly in reference to FIGS. 10 and 11. Disengagement of the clutch and relative linear movement between a friction surface, not shown, and the embodiment of a clutch shown in FIGS. 12 and 13 is accomplished by pushing movable housing 110 in the direction it is desired to move the housing and attached structure. The housing moves in the same plane in which the pawls move.

The embodiment of a clutch device of this invention, illustrated particularly in FIGS. 14 and 15, includes a clutch device 138 which has a clutch support 140. Clutch support 140 is an extension of lens holder 34. A housing 142 is mounted on clutch support 140. A piston 144 is slidably mounted for axial movement in housing 142. Clutch fingers 146 and 148 are linked to and movable with piston 144. Friction pawl 150 is pivotally mounted to clutch support 140 by means of pawl pivot pin 152 and is provided with an inner opposed side 154, an outer opposed side 156, and an outer end tip 158. Friction pawl 160 is pivotally mounted on pawl pivot pin 162 for rotation in the same plane as friction pawl 150. Friction pawl 160 is provided with an inner opposed side 164, an outer opposed side 166, and an outer end tip 168. The preload torsion spring 170 is positioned between friction pawls 150 and 160 and is mounted on spring retainer pin 172. Spring retainer pin 172 is mounted on clutch support 140. Preload torsion spring 170 is positioned to act against the inner opposed sides 154 and 164 of respective friction pawls 150 and 160 so as to bias the outer end tips 158 and 168 outwardly in opposite directions along friction surface 40. Piston 144 is slidably mounted in the same plane as the plane in which friction pawls 150 and 160 rotate. The interaction of the clutch fingers and the friction pawls in cooperation with surface 40 to effect holding or movement in the desired direction is the same as that described hereinabove, particularly in reference to FIGS. 8 and 9. As described above, one of the pawls acts as a reverse release pawl, which resists movement along a friction surface in one direction and permits movement along the same friction surface in the reverse direction. Another of the pawls acts as a forward release pawl, which resists movement in the reversed direction but permits movement in the opposite forward direction. The clutch fingers 146 and 148 are linked together with piston 144 into a generally C-shaped configuration in which the friction pawls 150 and 160 are mounted within the open C with their outer end tips 158 and 168, respectively, extending through the open side of the C. The ends of the C form the clutch fingers 146 and 148, which are positioned in contact with the outer opposed sides 156 and 166, respectively, of friction pawls 150 and 160. The deflected position of pawl 150 is illustrated in phantom in FIG. 15.

In the embodiment, illustrated in FIG. 16, a clutch device 174 is provided with a housing 175 which is mounted on a clutch support 176. A generally T-shaped clutch finger 178 is mounted on piston 179. Piston 179 is slidably mounted for axial movement in housing 175. Friction pawls 180 and 190 are mounted for pivotal movement in a common plane on clutch support 176 by means of pawl pivot pins 182 and 192, respectively. Friction pawls 180 and 190 are provided respectively with inner opposed sides 184 and 194, outer opposed sides 186 and 196, and outer end tips 188 and 198. A preload torsion spring 200 is mounted between the friction pawls 180 and 190 on spring retainer pin 202. Friction pawls 180 and 190 are mounted so that they are spring biased inwardly. Outer end tips 188 and 198, respectively, are adapted to normally engage friction surface 40 at such a location that lines extending normal to friction surface 40 from the point where the outer end tips contact surface 40 will pass on the outer sides of the respective pawl pivot points. The tips of the arms of the T-shaped clutch finger 178 contact the respective inner opposed sides 184 and 194 of the friction pawls. The coaction of piston 179, clutch finger 178, and the friction pawls to the effect the disengagement and movement of the clutch device 174 follows the same principles as described hereinabove, particularly with reference to FIGS. 10 and 11.

In the embodiment, illustrated particularly in FIGS. 17 and 18, there is illustrated a clutch device 204, including a clutch support 206 and a movable housing 208. Clutch fingers 210 and 212 are carried by movable housing 208. Friction pawls 214 and 226 are pivotally mounted on clutch support 206 by means of pawl pivot pins 216 and 228, respectively. Pivot pin relief slots 218 and 230 are provided in movable housing 208. The respective pawl pivot pins are journaled in these pivot pin relief slots. The pivot pins and the frictional pawls are mounted in a stationary position on clutch support 206. Frictional pawls 214 and 226 are provided respectively with inner opposed sides 220 and 232, outer opposed sides 222 and 234, and outer end tips 224 and 236. A preload torsion spring 238 is positioned between friction pawls 214 and 226 and is mounted on spring retainer 240. The friction pawls 214 and 226 are biased outwardly in opposite directions by means of preload torsion spring 238. Clutch fingers 210 and 212 are mounted on and carried by movable housing 208 into engagement with the respective outer opposed sides 222 and 234 of respective friction pawls 214 and 226. The friction pawls 214 and 226 are mounted so that a line extending normal to friction surface 40 from the point where the outer end tip of the respective friction pawl contacts surface 40 passes inside of the respective pawl pivot pin. The action of preload torsion spring 38 is one of wedging the outer end tips of friction pawls outwardly against friction surface 40. Spring 38 tends to force pawl 214 to rotate clockwise, and to force pawl 226 to rotate counterclockwise in the same plane. The release and movement of clutch device 204 relative to friction surface 40 is accomplished substantially as described hereinabove, particularly with reference to FIGS. 14 and 15, except that clutch fingers 210 and 212 are carried on movable housing 208 rather than on a piston slidably received in a stationary housing.

In the embodiment, illustrated particularly in FIG. 19, a clutch device 242 is provided with a movable housing 246. Clutch finger 248 is mounted on and movable with housing 246. Friction pawls 250 and 258 are pivotally mounted for rotation in a common plane stationary with respect to visor lens holder 34. The friction pawls are rotatable in a plane which is parallel to the plane in which relative movement between clutch device 242 and a friction surface, not shown, is effected. Friction pawls 250 and 258 are pivotally mounted on pawl pivot pins 252 and 260, respectively. Pivot pin release slots 254 and 262 are provided in movable housing 246 to permit stationary pawl pivot pins 252 and 260 to be received and journaled in movable housing 246. The outer end tips 256 and 264 of respective friction pawls 250 and 258 project outwardly through openings in housing 246 and are adapted to engage with a friction surface, not shown. A preload torsion spring 266 is provided to bias friction pawls 250 and 258 inwardly towards one another. The operation of clutch device 242 is similar to that described hereinabove, particularly with reference to FIGS. 9 and 10, except that clutch finger 248 is carried by movable housing 246 rather than by a movable piston slidably received in a fixed housing.

The two transparent visor lenses 30 and 32, FIGS. 1 and 2, are provided with different light transmission characteristics; so by alternately extending and retracting one or both of the visors, a wide variety of ambient light conditions may be compensated for. The visor housing 20 provides a durable protective housing into which the visor lenses 30 and 32 may be retracted when the helmet is not in use so as to protect the transparent visors from scratches and other damages.

What has been described are preferred embodiments in which modifications and changes may be made without departing from the spirit and scope of the accompanying claims.

Claims

What is claimed is:

1. A visored helmet having an open front and closed sides adapted to be worn by a person, said helmet comprising:

a visor lens mounted on said helmet for movement between a position over said open front and a position withdrawn from said open front;

a friction surface mounted on said helmet;

a latch including;

a latch support mounted on said visor lens;

at least two friction pawls pivotally mounted on said latch support, the shortest distance between said friction surface and the respective pivot point of each pawl being less than the respective length of each pawl from its pivot point to its outer tip end, means normally biasing the outer tip ends of said pawls in opposite directions into frictional engagement with said friction surface, and means for selectively releasing one of said pawls from contact with said friction surface by moving one said pawl against said biasing means.

2. A helmet as in claim 1 wherein each of said pawls is adapted to resist the relative movement of the friction surface toward said pawl from the other said pawl, the means for selectively releasing said pawls including latch fingers operatively disposed adjacent the respective pawls, whereby movement of a latch finger toward the adjacent pawl deflects the pawl towards the other said pawl and permits the relative movement of the frictional surface toward the deflected pawl from the other said pawl.

3. A helmet as in claim 1 wherein the friction pawls are biased toward one other and each of said pawls is adapted to resist the relative movement of the frictional surface from said pawl toward the other said pawl, the means for selectively releasing said pawls including latch fingers operatively disposed adjacent the respective pawls, whereby movement of a latch finger toward the adjacent pawl deflects the pawl away from the other said pawl and permits the relative movement of said frictional surface from said deflected pawl toward the other said pawl.

4. A helmet as in claim 1 wherein the means for releasing includes a plurality of latch fingers linked together positioned adjacent the respective outer opposed sides of said pawls and said pawls are biased outwardly in opposite directions.

5. A helmet as in claim 1 wherein the means for releasing includes a latch finger positioned between the respective inner opposed sides of said pawls and said pawls are biased inwardly toward one another.

6. A helmet as in claim 1 wherein there are two pivotally mounted friction pawls, said pawls being spring biased outwardly away from each other, a pair of latch fingers positioned respectively at the outer opposed sides of said pawls for movement with and against said spring force.

7. A helmet device as in claim 1 wherein there are two pivotally mounted friction pawls, said pawls being spring biased inwardly toward each other, a latch finger positioned between the respective inner opposed sides of said pawls for movement with and against said spring force.

8. A visored helmet of claim 1 wherein said helmet is provided with two visor lenses slidably mounted in superimposed relationship to one another, two of said friction surfaces mounted on said helmet, and one of said latches mounted on each of said visor lenses in operative association with a respective friction surface.

9. A visored helmet having an open front and closed sides adapted to be worn by a person, said helmet comprising:

a visor lens mounted on said helmet for movement between a position over said open front and a position withdrawn from said open front;

a friction surface mounted on said helmet;

a latch including;

a latch support mounted on said visor lens;

at least two friction pawls pivotally mounted on said latch support, means normally biasing the outer tip ends of said pawls into frictional engagement with said friction surface, said means biasing said pawls in opposite directions, each of said pawls being positioned in contact with said friction surface at a location slightly over center with respect to a plane extending vertically from said friction surface through the respective pivot point of said pawl, means for selectively releasing one of said pawls from locking engagement with said friction surface by the movement of the respective said pawl against the force of said biasing means, whereby upon release of a selected one of said pawls the other said pawl can slide over said friction surface and said visor lens can be moved in the desired direction.