The present invention generally relates to the field of bicycle helmets, and specifically to mechanisms for adjusting the size of bicycle helmets.
Bicycle helmets have progressed to be highly-engineered pieces of equipment. One important aspect of a bicycle helmet design is that it fit comfortably and securely on a user's head. One way of making a helmet comfortable and secure is to provide an adjustable harness that is secured inside the helmet shell and wraps around a user's head.
The present invention provides a helmet adjustment mechanism that is adapted to adjust the relative position of two parts of the helmet. The adjustment mechanism is particularly suited for bicycle helmets having a shell adapted to fit on a user's head, and first and second retention members (e.g., plastic straps having toothed slots) coupled to the shell and movable with respect to each other to adjust a size of the helmet. The adjustment mechanism is coupled to the retention members and includes an actuating member (e.g., a pinion) coupled to at least one of the retention members and movable (e.g., rotatable) in two directions to move at least one of the retention members relative to the other. The adjustment mechanism further includes a clutch mechanism coupled to the actuating member and including at least one locking member (e.g., two locking members) that inhibits movement of the actuating member in both of the two directions. The locking member is movable between a locked position, where the actuating member is substantially prevented from moving, and an unlocked position, where the actuating member is not substantially prevented from moving. The adjustment mechanism also includes a release mechanism (e.g., including a rotary dial) adapted to move the locking member from the locked position to the unlocked position to allow movement of the actuating member. When the actuating member is being moved, the adjustment mechanism also provides a ratcheting detent.
In one embodiment, the clutch mechanism includes a first locking member that inhibits movement of the actuating member in a first direction (e.g., counter-clockwise) and a second locking member that inhibits movement of the actuating member in a second direction (e.g., clockwise). Each of the first and second locking members is preferably movable between a locked position, where the actuating member is substantially prevented from moving in the respective direction, and an unlocked position, where the actuating member is not substantially prevented from moving in the respective direction. In this embodiment, the release mechanism is adapted to move the first locking member from the locked position to the unlocked position while simultaneously leaving the second locking member in the locked position to thereby allow the actuating member to move in the first direction. When the actuating member is being moved in the first direction, the second locking member can provide the ratcheting detent, but still retains its locking feature to prevent movement in the second direction.
In order to provide the locking feature, the clutch mechanism can include a series of clutch teeth for releasable engagement by the locking members. Preferably, the locking members each include a flexible arm having a latch portion (e.g., a latch tooth) for engaging the clutch teeth, and a first cam portion. In this embodiment, the adjustment mechanism can further include an input member (e.g., a rotary dial) movable by a user and including a second cam portion adapted to engage the first cam portion to move the locking member from the locked position to the unlocked position.
In one embodiment, the input member is movable relative to the clutch member between a static position and an adjusting position. In this embodiment, the locking member is in the locked position when the input member is in the static position, and movement of the input member to the adjusting position automatically moves the locking member to the unlocked position. Preferably, the input member further includes a drive portion adapted to drive the actuating member (e.g., tabs on the clutch member) when the input member is in the adjusting position.
Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings.
Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
The helmet 10 in
The helmet 10 further comprises a retention mechanism in the form of a harness 20 including several stabilizers (not shown) secured to the shell 12 (e.g., molded into the shell 12 or attached by mechanical, adhesive, or other means), as is known in the art. The harness 20 further includes a strap portion 24 designed to encompass a user's head. The strap portion 24 includes two ends that define first and second straps 26,28 that facilitate adjusting the size of the strap portion to accommodate different-sized heads. The harness 20 can be made from any suitable material, such as plastic, wire, woven fabric, and the like.
Referring to
The helmet 10 further includes an adjustment mechanism 38 for adjusting the straps 26,28 to fit the user's head size. The adjustment mechanism 38 includes a base member 40 designed to cover the occipital region of the user's head. The base member 40 is butterfly-shaped, and includes opposing bridge portions 42 through which the straps 26,28 are threaded. A base post 44 is positioned in a center region of the base member 40 such that it is positioned in the slots 30 of the straps 26,28 when the straps 26,28 are threaded through the bridge portions 42. Alignment walls 46 extend from the central region of the base member 40 on opposing sides of the base post 44 and are positioned to maintain the straps 26,28 in an overlapping relationship.
The adjustment mechanism 38 further includes an actuating member in the form of a pinion 50 rotationally mounted on the base post 44. Referring to
The adjustment mechanism 38 further includes a clutch mechanism that retains the pinion 50 in the desired position until an adjustment is desired. Referring to
Each flexible arm 64 extends from the clutch base 60 in a cantilever-like fashion such that a free end of each flexible arm 64 is able to resiliently flex and move relative to the clutch base 60. The end of each flexible arm 64 includes a latch tooth (i.e., a first latch tooth 68 and a second latch tooth 70) and a first cam portion including a ramped surface 72, the function of which will be described below in more detail. Due to its inherent flexible and resilient characteristics, when flexed radially-inwardly, each flexible arm 64 provides a radially-outward bias to the corresponding latch tooth 68,70.
Referring to
The cover member 82 includes a cylindrically-shaped recess 86 defined by a series of radially-inwardly facing cover teeth 88. When the adjustment mechanism 38 is assembled, the latch tooth 68,70 of each flexible arm 64 engages the cover teeth 88 in such a manner as to prevent rotation of the clutch member 65 relative to the base member 40 and cover member 82. More specifically, when viewed from the front of the helmet (
The adjustment mechanism 38 further includes a release mechanism that facilitates rotation of the clutch member 65 and pinion 50. Referring to
The dial 90 further includes second cam portions in the form of semi-cylindrical bumps 98 extending radially inward from the surface defining the cylindrical recess 96. As shown in
The dial 90 further includes opposing wedge-shaped recesses 100 that are defined by drive surfaces 102 on either end. Each wedge-shaped recess 100 is dimensioned to loosely receive one of the drive tabs 62 of the clutch member 65. In the neutral position (
In operation, the size of the helmet 10 can be adjusted by rotating the dial 90. When in the neutral or static position (i.e., with no user input to the dial 90), the bumps 98 on the dial 90 are adjacent to but not pressing against the ramped surfaces 72 (
When it is desired to tighten the helmet 10 (i.e., make the helmet 10 smaller), the dial 90 is rotated counter-clockwise (
Loosening of the helmet 10 (i.e., making the helmet 10 larger) is accomplished by rotating the dial 90 in the clockwise direction, as will be apparent to one skilled in the art. This operation is generally illustrated in