Abstract:
A dual visor operating mechanism in which respective locks disposed between inner and outer visor arm hubs and respective right and left arbors normally prevent movement of the visors in response to force applied directly thereto and in which respective inner and outer visor actuators sequentially release their associated brakes and then move the visors therewith. Brakes prevent movement of the visors after release of the associated lock and before the corresponding visor moves with the actuator.

Description:
FIELD OF THE INVENTION 
     The invention is in the field of operating mechanisms for dual visors carried by protective helmets or the like and relates to a dual visor operating assembly which overcomes the defects of dual visor operating assemblies of the prior art. 
     BACKGROUND OF THE INVENTION 
     There are known in the prior art protective helmets which are provided with inner and outer visors, each of which is mounted on the helmet for movement between an inoperative or retracted position and an operative position at which it is disposed in front of the eyes of the person wearing the helmet. Customarily, one of the visors is tinted and the other visor is clear. 
     Various mechanisms are known in the prior art for selectively moving the inner and outer visors between the retracted position and the operative position. In one form of such a device, the helmet carries a housing which receives the visors in their inoperative position. The mechanism for moving the visors between the inner and outer positions incorporates an element which moves along a slot which extends in a fore and aft direction in the visor housing. An example of a mechanism of this sort is shown in Long et al U.S. Pat. No. 4,887,320. In some instances it may not be desirable to provide the helmet with a visor housing. Further, the particular operating mechanism including the member movable along the housing slot may be relatively inconvenient to use or too cumbersome. 
     Other forms of dual visor operating assemblies incorporate tracks extending in a fore and aft direction on the helmet shell and along which an operating member may slide in the course of moving a visor between its operative and inoperative positions. An example of such an arrangement is shown in Aileo U.S. Pat. No. 3,748,657. Again, for one reason or another, an operating mechanism of this type may not be desirable. 
     Still another mechanism for moving a visor between its operative and inoperative positions is shown in Luisada et al U.S. Pat. No. 3,636,565. That patent shows respective normally locked knobs on the sides of the helmet which can be released and individually rotated to move the respective inner and outer visors between their operative and inoperative positions. The mechanisms for achieving this result, however, are relatively complicated and expensive. In addition, they have a relatively high profile which in many instances is objectionable. 
     Still another form of dual visor operating mechanism is shown in our application Ser. No. 07/588,686, filed Sep. 26, 1990. In the arrangement shown therein, the respective inner and outer visors are pivotally supported for movement between their operative and inoperative positions by means of arbors located at the respective sides of the helmet shell. Releasable means is provided for frictionally clamping the visors to the arbors. This arrangement has the advantage of a low profile and infinite adjustment. A limitation, however, is the reliance on friction alone to hold the visor in its adjusted position. Stated otherwise, the arrangement does not provide a positive lock. 
     Still another form of dual visor operating mechanism is shown in Higgs U.S. Pat. No. 4,170,792. In the arrangement shown in the Higgs patent a clutch output member carried by the visor is rotatably supported on a cylindrical boss secured to the helmet shell. A cutout in the clutch output member receives a pair of balls which are urged by respective springs toward the central reduced diameter portion of the cutout to wedge the balls between the boss and the clutch output member. Any force exerted directly on the visor in an effort to move it up or down is resisted by the wedging action of the balls. A knob rotatably supported on the boss carries a clutch release element disposed between the balls and adapted to be moved into engagement with one or the other of the balls to move it against the action of its spring to a relatively larger diameter portion of the cutout to release the visor for movement with the knob to an adjusted position in which it is locked by the balls. 
     While the Higgs patent provides infinite adjustment of the position of the visor and a relatively positive locking action, it incorporates a number of defects. First, the operation of the device is not as smooth as is desired. More particularly, if the visor is in the up position and the person wearing the helmet actuates the knob to move the visor down, after the ball which had been holding the visor in the up position is moved to the release position, the weight of the visor itself causes it to get ahead of the wearer&#39;s movement of the knob so that the visor moves down in a number of steps. That is to say, in the course of the wearer&#39;s movement of the knob from the up position to the desired down position, the visor falls down a short distance, is locked again, is unlocked, and moves down another short distance through gravity until it is again stopped. This operation continues until the desired adjusted position is reached. 
     SUMMARY OF THE INVENTION 
     One object of our invention is to provide a dual visor actuating assembly which overcomes the defects of dual visor operating assemblies of the prior art. 
     Another object of our invention is to provide a dual visor operating mechanism which permits of infinite adjustment of the position of the visor between operative and inoperative positions. 
     Yet another object of our invention is to provide a dual visor operating mechanism which affords infinite adjustment of visor position while at the same time affording a positive lock of the visor in its adjusted position. 
     A still further object of our invention is to provide a dual visor operating mechanism which is smooth in its operation. 
     Other and further objects of our invention will appear from the following description. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In the accompanying drawings to which reference is made in the instant specification and which are to be read in conjunction therewith and in which like reference numerals are used to indicate like parts in the various views. 
     FIG. 1 is a side elevation of a helmet provided with our improved dual visor operating mechanism. 
     FIG. 2 is a sectional view of the helmet shown in FIG. 1 taken along the line 2--2 of FIG. 1 and drawn on an enlarged scale. 
     FIG. 3 is an exploded view of our improved dual visor operating mechanism for operating one of the visors of the helmet shown in FIG. 1. 
     FIG. 4 is a sectional view of our improved visor operating mechanism for one of the visors of the helmet shown in FIG. 1. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring now to the drawings, our improved dual visor operating mechanism to be described more fully hereinbelow, may be applied to a helmet indicated generally by the reference character 10 made up of a shell 12 with which there are associated an outer visor 14 and an inner visor 16. We provide respective left-hand and right-hand operating mechanisms indicated generally by the respective reference characters 18 and 20 for the inner and outer visors 16 and 14. 
     In the embodiment of our assembly illustrated in the drawings, the left-hand assembly 18 is adapted to operate the inner visor 16 and to permit the outer visor 14 to rotate relative thereto. The assembly 18 includes a left-hand base 22 formed with a reduced diameter portion 24 and secured to the shell 12 by any suitable means such for example as by screws 26 and 28. It will be appreciated that base 22 on its reduced diameter portion 24 constitute an arbor. 
     We secure the left-hand inner visor arm 30 to the left-hand side of the inner visor 16 by any suitable means, such for example as by rivets 32. The arm 30 has a hub 34 formed with an opening 36 which receives an outer clutch ring 38 of our assembly. The outer ring 38 is secured to the hub 34 for rotation therewith. It is to be understood that while we have shown the outer ring 38 and the arm 30 as being separate parts, they can be formed as a single integral element. 
     Referring now to FIG. 4, we form the outer ring 38 with three variable diameter 40, 42 and 44 separated by constant diameter portions 46, 48 and 50. As will be explained more fully hereinbelow, the end regions of each of the portions 40, 42 and 44 are of relatively larger diameter than are the central areas of these portions. Moreover, the diameter of the constant diameter portions 46, 48 and 50, is less than the diameter of the outer areas of the portions 40, 42 and 44 so as to form shoulders between the ends of the constant diameter portions and the adjacent ends of the variable diameter portions. 
     Our operating mechanism 18 includes respective pairs of rolling elements such as rollers or balls 52 and 54, 56 and 58, and 60 and 62, the respective balls of each pair of which are located in adjacent variable diameter portions of the ring 38. Specifically, balls 62 and 52 are located in portion 40. Balls 54 and 56 are located in portion 42 and balls 58 and 60 are located in portion 44. 
     Respective compression springs, 64, 66 and 68 located in the constant diameter portions 46, 48 and 50 are disposed between the respective balls of the pairs of balls 52 and 54, 56 and 58 and 60 and 62. Each spring urges the balls of its associated pair away from each other and into engagement with the reduced diameter region of the variable diameter portion in which the ball is disposed. 
     Referring to FIGS. 2 to 4, the mechanism 18 includes an actuator 70 having a central opening 72 which receives the reduced diameter part 24 of the base 22. We provide the actuator 70 with three protuberances or bosses 74, 76 and 78 extending into the space between the outer race 38 and the reduced diameter portion 24. The bosses 74, 76 and 78 are disposed respectively between the balls of the pairs of balls 62 and 52, 54 and 56 and 58 and 60. 
     An outer arm base 82 is disposed in an opening 90 formed in a hub 88 of the left-hand outer visor support arm 84. Any suitable means, such for example as screws or nuts or rivets 86, secure the arm 84 to the outer visor 14. 
     A knob 92 forming part of the assembly 18 has a partial peripheral flange 94 which extends downwardly and into operative engagement with the actuator 70 so that when the knob is turned the actuator will move. 
     For a reason to be described more fully hereinbelow, we dispose a drag ring or braking element 96 around the base 22. We form the drag ring 96 with a gap 98 which receives a tang 100 formed on the hub 34 of the inner visor arm 30. It is to be understood that the arrangement of parts is such that the drag ring 96 exerts a frictional force creating a braking action which prevents the arm 30 from rotating freely relative to hub portion 24. It will be seen that the portions of the drag ring or braking element 96 at the sides of gap 98 and the tang 100 formed on the hub 34 of the visor arm 30 carried by the inner visor 16 constitute interengageable means on the drag ring or braking element 96 and on visor 16. 
     A screw 102 secures the parts of the mechanism 18 in operative relationship to the reduced portion 24 and the base 22. 
     The mechanism 20 includes a right-hand inner visor arm base 104 secured at the proper location on the shell 12 by means of screws 106 and 108. Base 104 is received in an opening 116 in the hub 114 of the right-hand inner visor arm 110. We employ any suitable means, such for example as rivets 112, for securing the inner visor 16 to the arm 110. As will be apparent from the description hereinafter, arm 110 rotates relative to the base 104 when the mechanism 18 is actuated. 
     Screws 106 and 108 also secure an outer arm base 118 having a reduced diameter portion 120 to the shell 12. Base 118 with its reduced diameter portion 120 constitute arbor. We secure the outer visor 14 to a right-hand outer visor arm 122 by any suitable means, such for example as screws and nuts or rivets 124. Arm 122 has a hub 126 formed with an opening 128 which receives the outer ring 3 of the mechanism 20. It will readily be appreciated that if desired, we may form the outer ring 130 integrally with the hub 126 of the arm 122. Outer ring 130 is formed with raceway portions which are the same as those described hereinabove in connection with outer race 38. In addition, the space between the outer ring 130 and the reduced diameter portion 120 of base 118 receives sets of rollers or balls and springs in the same manner as does the space between the outer ring 38 and the reduced diameter portion 24. 
     Mechanism 20 includes an actuator 140 having an opening 142 which receives the reduced diameter portion 120. We form the actuator 140 with three projections or bosses, one boss 144 of which is shown in FIG. 2. These projections or bosses are disposed between the pairs of balls associated with mechanism 20 in the same manner as are the bosses 74, 76 and 78 of the mechanism 18. We form the actuator 140 with a skirt 146 extending partway around the actuator. 
     A knob 148 forming part of the assembly 20 has a partial peripheral flange 15 which extends downwardly and into operative engagement with the skirt 146 so that when the knob 148 is turned, the actuator 140 will move. 
     The mechanism 20 includes a drag ring 152 formed with a discontinuity similar to the discontinuity 98 in the drag ring 96. A tang 154 formed on the hub 126 of the arm 122 extends into the opening or discontinuity of the drag ring 152. 
     A screw 156 threaded into the reduced diameter portion 120 of the base 118 holds the parts of the mechanism 20 in assembled relationship. From the foregoing it will be seen that means mounting the inner visor 16 on the helmet shell 12 is constituted at the left, as viewed in FIG. 2, by arm 30, hub 34, actuator 70 and portion 24 of base 22 and at the right, as viewed in FIG. 2, by arm 110 and base 104. Similarly, means mounting the outer visor 14 on the helmet shell is constituted at the left, as viewed in FIG. 2, by arm 84 and base 82 and at the right by arm 122, hub 144 and portion 120 of base 118. 
     In operation of our improved dual visor operating mechanism, each of the visors 14 and 16 is held in position by the wedging action of the balls of the respective operating mechanisms 18 and 20. For example, the inner visor 16 is held in position by the action of the pairs of balls 52 and 54, 56 and 58 and 60 and 62. Balls 54, 58 and 62 prevent rotation of the arm 30 on boss 24 in a counter-clockwise direction as viewed in FIG. 4. The other balls 52, 56 and 60 prevent rotation of the arm 30 around the boss 24 in a clockwise direction. It will be seen that the pairs of balls 52 and 54, 56 and 58 and 60 and 62, under the action of springs 64, 66 and 68, cooperate with the shoulders at the ends of constant diameter portions 46, 48 and 50 of ring 38 to provide a releasable lock for holding the visor 16 in the position to which it has been moved. Mechanism 20 provides a similar releasable lock for visor 14. 
     If it is desired to lower the visor 16, knob 92 is turned in a counterclockwise direction as viewed in FIG. 4, around the boss 24 to cause the actuating elements 74, 76 and 78 to engage balls 52, 56 and 60 and move them into the relatively larger diameter end regions of the portions 40, 42 and 44. As soon as the balls are freed, the visor 16, in the absence of drag ring 96, would be free to move, falling by its own weight. However, owing to the engagement of the tang 100 disposed in the gap 98 of the drag ring 96, the visor is restrained against movement by the gripping action of the drag ring until the balls 54, 58 and 62 have been moved into engagement with the respective shoulders between portions 40, 42 and 44 and the adjacent portions 46, 48 and 50 by rotation with the knob. When this engagement takes place, the visor can be moved smoothly with the knob to its new adjusted position. A similar action takes place when the knob 92 is moved in a clockwise direction around the boss 24 to raise the visor 16. Since the operation of the mechanism 20 is substantially the same as that of the mechanism 18, no detailed description of the former will be given. 
     It will be seen that we have accomplished the objects of our invention. We have provided a dual visor operating mechanism which overcomes the defects of dual visor operating mechanisms of the prior art. Our mechanism affords infinite adjustment of the visor between its raised and lowered positions. At the same time, it provides a positive lock of the visor in its adjusted position. Our mechanism ensures a smooth movement of both the inner and outer visors to any position between their operative and inoperative positions. 
     It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of our claims. It is further obvious that various changes may be made in details within the range of our claims without departing from the spirit of our invention. It is, therefore, to be understood that our invention is not to be limited to the specific details shown and described.