Rotating multicolored air driven reflector

A rotatable reflector for bicycles has a timer which intermittently completely halts rotation of the reflector in sequential positions in response to rotation of the reflector but independently of angular movement of a bicycle wheel. The reflector displays a changing colored reflective surface above a stationary housing of a contrasting color. The timer is liquid actuated and can be accurately calibrated by varying the viscosity of the liquid in the timer. Timed display of contrasting colored portions of the reflector attracts the attention of passing motorists by displaying a signal which appears to blink and change colors. The period during which each contrasting color is displayed is constant regardless of the velocity of the bicycle or relative wind velocity.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to a reflector for bicycles and similar 
vehicles, and particularly to a reflector which displays contrasting 
reflective colors that appear to be flashing. 
2. General Discussion of the Background 
Rotating bicycle reflectors have already been disclosed which have a 
reflecting surface movable with respect to the frame of reference of the 
bicycle in order to create a flashing effect when the reflecting surface 
is viewed from a point outside of the frame of reference of the bicycle. 
For example, U.S. Pat. No. 4,046,098 shows a multisurface reflector which 
is mounted on a bicycle and connected to a transmission line which moves 
the reflector assembly in direct response to angular rotation of a bicycle 
wheel. U.S. Pat. No. 4,105,286 discloses a reflector assembly which is 
similarly driven by angular rotation of a bicycle wheel or air driven by a 
fan mechanism that rotates in response to relative air velocity created by 
movement of the bicycle. U.S. Pat. No. 4,204,746 shows a similar air 
driven, rotary signal which continuously rotates a reflecting member in 
response to the relative velocity of air as a bicycle is moving. U.S. Pat. 
Nos. 3,578,840 and 4,003,630 show reflectors of unusual shapes that are 
continously rotated in response to relative air currents created by 
movement of the bicycle. 
Some unfortunate drawbacks of many of the aforementioned rotary reflectors 
are that they continuously rotate and that the speed of their angular 
rotation is a function of the angular velocity of a bicycle wheel or 
relative air velocity arising from movement of the bicycle. As the bicycle 
velocity or relative air velocity increases, angular rotation of the 
reflector proportionately increases until any contrasting colors on the 
reflector blur into a single color. The high visibility advantage of a 
rotating reflector is thereby lost, since the rapidly rotating reflector 
becomes visibly indistinguishable from a stationary reflector. 
European Patent Application No. 014986 recognized this problem and 
attempted to overcome it by providing a centrifugal brake which slows 
rotation of a rotating reflector when the reflector rotates faster than a 
preselected speed. The centrifugal brake never completely halts rotation 
of the reflector, however, and therefore never transmits a dramatically 
contrasting signal to oncoming vehicles. 
U.S. Pat. No. 4,046,098 interposed a Geneva mechanism in a rotary 
transmission line to intermittently rotate the bicycle reflector. 
Rotational velocity of the reflector was nonetheless a function of the 
rotational velocity of the bicycle wheel, and at very high speeds the 
reflector would appear to rotate almost continuously. This was especially 
true since the period during which rotation of the reflector was 
interrupted grew progressively shorter as angular velocity of the bicycle 
wheel increased. 
It is therefore an object of the present invention to provide a bicycle 
reflector which maximizes visibility of the reflector to oncoming traffic 
and other observers. 
Yet another object of this invention is to provide such a reflector having 
a simple mechanism for maintaining visioility of contrasting colored faces 
of the reflector which are displayed to oncoming vehicles. 
It is another object of the present invention to provide a bicycle 
reflector having a timing mechanism that operates independently of angular 
rotation of a bicycle wheel. 
It is a still further object of the present invention to provide a bicycle 
reflector which presents minimal air resistance to movement of a bicycle 
to which it is attached. 
These and other objects of the invention will become apparent after reading 
the following detailed description. 
SUMMARY OF THE INVENTION 
The foregoing objects are achieved by providing a rotatable reflector 
assembly with a timer which intermittently completely halts rotation of 
the reflector in sequential positions in response only to rotation of the 
reflector and independently of angular movement of the bicycle wheels. 
In preferred embodiments, the reflector assembly includes a cylindrical, 
rotatable reflector having an open face for admitting air to the interior 
of the reflector, a closed face which forms a reflective surface, and a 
plurality of air vanes through the closed face for rotating the reflector 
about an axis through the closed face in response to movement of air 
through the cylinder. A timer carried by the cylindrical reflector 
intermittently completely halts rotation of the reflector after each half 
rotation independently of angular rotation of the wheel as the reflector 
rotates. 
A reflective housing partially encloses the cylindrical reflector such that 
only a half-cylindrical top portion of the reflector is visible above the 
housing. Each half-cylindrical portion of the reflector which is visible 
above the housing is a contrasting color, and the color of the housing 
itself differs from either half of the cylinder. Each time the cylinder 
stops rotating, it displays a contrasting color above the housing which is 
different from the color displayed by the other half of the cylindrical 
reflector during the last timed delay in rotation. The reflector appears 
to blink a different color duirng each timed delay, and the period of 
delay during which each color is displayed is constant. 
In preferred embodiments, the timer includes a pair of closed, opposing 
chambers on either side of the axis about which the reflector rotates. 
Each chamber is divided by a movable, flexible diaphragm, and a stop pin 
is carried by each diaphragm such that each stop pin moves with the 
diaphragm to which the pin is attached. The closed chambers are 
interconnected by a tube carried by the reflector. A liquid can move 
through the tube to exert a pressure on one or the other of the movable 
diaphragms and alternately reciprocate the pins such that one pin is 
extended while the other is retracted. A pin stop, which is stationary 
relative to the rotating reflector, is positioned within the cylindrical 
reflector adjacent the top of the timer to engage a pin when the pin is 
extended but not when the pin is retracted. Rotation of the reflector is 
halted after each one-half rotation of the cylindrical reflector, and 
rotation does not resume until sufficient fluid has passed down through 
the tube to retract the engaged pin and move it out of engagement with the 
stop. As the engaged pin retracts, the other pin concomitantly extends in 
response to movement of liquid moving down through the tube which expands 
the diaphragm in the bottom chamber. After a one-half rotation of the 
reflector, the extended pin engages the stop and begins to retract as the 
nonengaged pin begins to extend. The reflector continues to be 
intermittently rotated and stopped for a constant period as long as 
relative air velocity acts on the wind vanes to rotate the reflector. 
Liquid moves through the tube of the timer independently of the angular 
velocity of the bicycle wheels or reflector. The timer's period of delay 
is a function only of the viscosity of the liquid. The period of delay is 
therefore constant as bicycle velocity or relative air velocity changes.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
A rotatable reflector assembly 10 for bicycles and similar vehicles is 
shown mounted on a rear portion of a conventional bicycle 12. The 
reflector assembly 10 includes a rotatable reflector 14 having a 
cylindrical body 16, open end 18, and closed end 20. The closed end forms 
a frustoconical face 22, which includes a circular flat central portioh 24 
circumscribed by a sloping shoulder 26 which connects central portion 24 
to cylindrical body 16. 
Cylindrical body 16 is divided into semicylindrical halves 28, 30 (FIG. 1). 
Halves 28, 30 have an exterior surface which is covered with a reflective 
colored material. The colors of halves 28, 30 are contrasting, for 
example, half 28 is yellow and half 30 is red. 
A rotating means is provided for rotating reflector 14. In the disclosed 
embodiment, the rotating means includes a plurality of wind vanes 32 
through shoulder 26. Each vane 32 includes a punched flap 34 having a top 
surface which is continuous with the surface of shoulder 26. Each flap 34 
is slightly curved as shown in FIG. 6 to help preserve the continuity of 
the surface of the shoulder 26. Each flap 34 also covers a corresponding 
cutout portion 36 (FIGS. 1 and 6) through which air can pass in the 
direction shown by arrows 38 (FIG. 6). The tip of each flap 34 should 
completely cover its corresponding cutout 36 when viewed from above each 
flap to prevent interruption of the colored signaling surface. 
Reflector 14 is rotatably mounted in a housing 46 which encloses a 
semicylindrical portion of body 16, the housing 46 being about as high as 
a radius of cylindrical body 16. The exterior color of housing 46 is 
preferably blue or any other color that contrasts with the red and yellow 
colors of semicylindrical portions 28, 30. Housing 46 includes sidewalls 
48, 50 and bottom 52 interconnected by sloping walls 54, 56. A rear wall 
60 extends across the rear of housing 46. A front face of housing 46 is 
substantially open, being only partially obscured by an upstanding 
triangular bracket 66 which extends upwardly from bottom 52. A pair of air 
ports 62, 64 are provided through sloping walls 54, 56 near rear wall 60 
to allow air which enters cylindrical body 16 to leave the reflector body 
without exerting undue drag on bicycle 12. 
Housing 46 can be secured to bicycle 12 above the rear fender of bicycle 12 
by a pair of supports 67 (only one being shown in FIG. 1) which extend 
between sidewalls 48, 50 of housing 46 and the axle (not shown) of the 
rear wheel. Another support 68 extends between the base of the seat of 
bicycle 12 and triangular bracket 66 of housing 46. Supports 67, 68 
thereby prevent horizontal or vertical displacement of reflector 14 with 
respect to bicycle 12. It will be apparent that reflector 14 can be 
attached to bicycle 12 in a variety of positions and in a variety of ways. 
An axle 72 (FIGS. 2 and 4) extends between rear wall 60 and triangular 
bracket 66, the axle being free to rotate with respect to housing 46. Axle 
72 is retained in place by an enlarged head 74 (FIGS. 3 and 4) against 
rear wall 60 and a retainer 76 (FIGS. 2 and 4) against triangular bracket 
66. 
A timing means is carried by reflector 14 for completely halting rotation 
of reflector 14 after each one-half rotation of the reflector. The timing 
means is positioned inside cylindrical body 16 and includes first and 
second closed, domed chambers 78, 80 positioned in opposing relationship 
on either side of axle 72. A conduit 82 extends perpendicularly to axle 72 
and interconnects the chambers 78, 80. Conduit 82 has an enlarged center 
section 84 which maintains the internal cross-sectional area of conduit 82 
constant around axle 72 to allow an unimpeded flow of a liquid 126 through 
the conduit while also allowing axle 72 to be inserted through an opening 
formed by the enlarged center section 84 of conduit 82. Each end of 
conduit 82 is constricted at 86, 88 for impeding the flow of liquid 126 
out of conduit 82 into chambers 78, 80. 
A flexible expandable circular diaphragm 94 (FIGS. 4 and 5) divides first 
chamber 78 into a liquid filled first sector 98 which fluidly communicates 
with conduit 82, and a dry second sector 100. A second flexible expandable 
circular diaphragm 102 similarly divides chamber 80 into a liquid filled 
first sector 104 and a dry sector 106. Each of diaphragms 94, 102 is 
movable between a constricted position and an expanded position. The first 
sector 98, 104 of each chamber has a greater volume when its respective 
diaphragm 94 or 102 is in the expanded position. FIG. 4, for example, 
shows diaphragm 94 in an expanded position and diaphragm 102 in a 
restricted position. 
A pin 110 is attached to the center of diaphragm 94 by a fastener 112 and 
the pin projects out of an opening 113 in the domed top of chamber 78. 
Another pin 114 is attached to the center of diaphragm 102 by a fastener 
116, and pin 114 projects out of opening 116 in the domed top of chamber 
80. Each of pins 110, 114 moves between a retracted position when the 
diaphragm which carries the pin is constricted, and an extended position 
when the diaphragm which carries the pin is expanded. In FIGS. 4 and 5, 
for example, pin 110 is extended because diaphragm 94 is expanded, while 
pin 114 is retracted because diaphragm 102 is constricted. 
A stationary, L-shaped pin stop 120 (FIGS. 2, 4, and 5) is mounted to 
bracket 66 at the point at which bracket 66 supports axle 72. Stop 120 
extends upwardly from bracket 66 and inwardly into the interior of 
cylindrical reflector 14 to provide a surface against which each pin 110 
or 114 stops when the pin is extended. An upwardly projecting leg of stop 
120 extends upwardly from bracket 66 a distance less than the radius of 
body 16 yet greater than the distance of chambers 78, 80 from axle 72. An 
inwardly projecting leg of stop 120 extends into reflector 14 a sufficient 
distance to intersect the path of each pin 110, 114 when either pin is 
extended. Each of cylindrical body 16 and stop 120 have an alignable hole 
122 through which the shank of a lock pin 124 can be placed selectively to 
prevent rotation of reflector 14. 
The timing mechanism is partially filled with liquid 126 which occupies 
conduit 82 and first sectors 98, 104. A sufficient volume of liquid 126 is 
provided such that, when the chambers 78, 80 of the timing mechanism are 
in the up-down orientation shown in FIGS. 4 and 5, the diaphragms are 
positioned such that pin 110 is extended beyond the domed top of chamber 
78 and the other pin 114 is retracted within the domed surface of chamber 
80. 
Liquid 126 is preferably a nontoxic liquid which has a substantially 
constant viscosity across a broad range of temperatures such that the 
timer can be calibrated to completely halt rotation for an invariable 
period of delay. Mineral oil is a suitable liquid for this purpose. 
Propylene glycol or other commercial antifreeze preparations satisfy the 
requirement for substantially constant viscosity across a broad 
temperature range but suffer from the drawback of being toxic. 
In operation, bicycle 12 moves in the direction of arrow 130 (FIG. 1), 
which creates a relative air velocity in the direction of arrows 132. Air 
enters open end 18 of cylindrical body 16 to create a slightly higher 
differential air pressure within body 16 which forces air out of the body 
through cutout portions 36 of vanes 32. Flaps 34 direct the air at an 
angle to axle 72, which creates a torque that results in a rotary thrust 
that rotates reflector 14 about axle 72. Ports 62, 64 allow air to leave 
housing 46, thereby avoiding a build up of air pressure within the housing 
which could diminish the differential pressure inside and outside 
reflector 14. 
The operation of the timer is illustrated in FIGS. 4 and 5. Extended pin 
110 has lodged against pin stop 120 and halted the air induced rotation of 
reflector 14 in a position in which only the red semicylindrical portion 
28 of reflector 14 is visible above blue housing 46. Immediately after pin 
110 has abutted stop 120, liquid 126 begins to move out of first sector 98 
of chamber 78 through restriction orifice 86 as shown by arrow 136 (FIG. 
5). Liquid drains into conduit 82, through section 84, and into first 
sector 104 of chamber 80. As liquid moves out of sector 98 and into sector 
104, diaphragm 94 of chamber 78 begins to constrict which retracts pin 110 
out of abutment with stop 120. Concomitantly, diaphragm 102 of chamber 80 
expands to extend pin 114. As soon as pin 110 retracts, the torque induced 
by movement of air through vanes 32 rotates reflector 14 in the direction 
of arrow 138 (FIG. 1) until pin 114 lodges against stop 120 after a 
180.degree. rotation of reflector 14, at which point only yellow portion 
30 of reflector 14 is visible above blue housing 46. Liquid 126 then 
immediately begins to drain out of chamber 80 through conduit 82 into 
chamber 78. Diaphragm 102 will accordingly restrict, which retracts pin 
114 and allows free rotation of reflector 14 in response to air induced 
torque. This sequence repeats each one-half rotation of the reflector. 
Reflector assembly 10 very effectively attracts the attention of passing 
motorists because it displays a signal which appears to blink and change 
colors. The timer operates independently of angular rotation of the 
bicycle wheel or relative wind velocity through the reflector. The timer 
can be accurately calibrated to achieve a constant period of delay by 
choosing liquids of various viscosities for the timer. The period during 
which no rotation occurs will be solely a function of the viscosity of the 
liquid chosen, since the liquid's viscosity determines how quickly it will 
flow through conduit 82 and move diaphragms 94, 102. 
Having illustrated and described the principles of the invention in a 
preferred embodiment, it should be apparent to those skilled in the art 
that the invention can be modified in arrangement and detail without 
departing from such principles.