GB2152247A - Timing device for stunt bicycle - Google Patents

Abstract

A timing device for a stunt bicycle includes a housing (2) for securing to the bicycle such that a time display panel (8) of the device is visible to a rider. The housing (2) contains a battery, dynamo or solar powered electronic timer including a movement-sensitive switching mechanism having a first condition associated with the bicycle in its normal position with two wheels on the ground, and a second condition associated with balanced movement of the bicycle on the rear wheel only. Control means (10) are operable to switch the timer into a first mode of operation (W) such that, on displacement of the bicycle into the balanced position for movement on the rear wheel only, the timer is automatically started and, on return of the bicycle to its normal position, the timer is stopped, the panel (8) then displaying the elapsed time of the period during which the bicycle was in the displaced position. <IMAGE>

Description

SPECIFICATION Timing device for stunt bicycle This invention relates to timing devices for attachment to stunt bicycles, for example rough terrain bicycles commonly known as BMX (bicycle motocross) bikes.

BMX bikes are currently very popular with the 5 to 1 6 age group, being of a very robust nature and designed specifically for stunt riding and for racing around tracks of rough, undulating terrain.

A particular popular stunt of riders of such bicycles is the 'wheelie' i.e. balancing the bicycle on its rear wheel and travelling along on said rear wheel only for as far as possible.

Currently the timing of such stunts, as well as the timing of races, has to be effected either by persons other than the riders, or by the riders themselves using hand-held stop watches. The requirement for the presence of third parties has clear disadvantages, while the rider himself cannot be intimately and immediately aware of his own performances.

The operating or reading of a hand-held stop watch by a rider while actually riding a bicycle can lead to unnecessary accidents.

It would be desirable to be able to provide a timing device for attachment to a stunt bicycle such as to enable a rider to time his own activities in a convenient and safe manner.

According to the present invention there is provided a timing device for a stunt bicycle, said device comprising a housing for attachment to the bicycle and including an electronic timer provided with an elapsed-time display panel for viewing by a rider, the timer including a movement-sensitive switching mechanism having a first condition associated with normal usage of the bicycle and a second condition effected only with the bicycle at the particular angle to the horizontal associated with balanced movement on the rear wheel (wheelie position), and manually-operated con trol means for actuating the timer, said control means being operable to switch the timer into a first mode of operation in which, on displacement of the bicycle into the wheelie position, the timer is automatically started, and, on subsequent return of the bicycle to its normal position, the timer is automatically stopped, an elapsed-time read-out of the period during which the bicycle was in the wheelie position being given on the display panel.

It will be appreciated that such an arrangement does not require any manual actuation of the timing device either during or after a wheelie to determine the length of the wheelie, it merely being necessary to switch the device to the first mode of operation of the timer at any time prior to the stunt being performed. In a preferred timing device, the display on the display panel is switched off during the stunt, only appearing as a read-out of the elapsed time once the bicycle has returned to its normal orientation. Thus, the rider cannot be distracted by the timing device during the stunt.

Conveniently the control means are also operable to switch the timer into a second mode of operation enabling subsequent controlled manual starting and stopping of the timer to give an elapsed-time read-out on the display panel of a period of standard riding of the bicycle.

In a preferred device the control means comprise a pair of button-operated switches the first of which can be moved from an off position to a first displaced position to switch the timer into its first mode of operation, and to a second displaced position to switch the timer into its second mode of operation, and the other of which switches enables controlled starting and stopping of the timer when the first switch is in its second displaced position.

Conveniently, the first and second displaced positions of the first switch are effected by rotation of the associated button, depression of said button resulting in resetting of the display on the display panel to zero, while the other switch is push-button operated, alternate depressions of the associated push-button starting and stopping the timer when the first switch is in its second displaced position.

The movement-sensitive switching mechanism preferably includes a mercury tilt-switch to effect the change from the first condition to the second condition, the precise orientation of said switch relative to the housing being adjustable from externally of the housing, conveniently by means of a grub screw.

The timing device may further include control means operable to switch the timer into a third mode of operation providing a real time read-out on the display panel.

Preferably the timing device is battery-operated and includes means for indicating when the battery output has fallen below a predetermined minimum level, which means may be such as to cause flashing of the display on the display panel, while the device may further include means in the display panel indicating the mode of operation of the device at any given time. It is preferred that all read-out displays on the panel are digital liquid crystal displays.

By way of example only, an embodiment of the invention will now be described in greater detail with reference to the accompanying drawings of which: Fig. 1 is a front view of a timing device according to the invention in position on the handlebars of a bicycle; Fig. 2 is a side view of the device shown in Fig. 1, and Fig. 3 is a schematic circuit diagram of the timer of the device of Figs. 1 and 2.

Referring to the drawings, the illustrated timing device comprises a piastics housing 2 provided with a pair of clamps 4 to enable the device to be secured to the handlebars 6 of a BMX bicycle at the central regions of said handlebars above the front wheel.

The face of the housing 2 presented to the rider incorporates a display panel 8, a pair of control buttons 10,12 being located on said face one either side of the panel 8. The housing 2 has a particular operative position relative to the horizontal as will be described in more detail below and as can be seen most clearly in Fig. 2.

Contained within the housing 2 is a batteryoperated electronic timer the circuit of which is shown schematically in Fig. 3 and operation of which is under the control of the buttons, 10,12, the timer providing an elapsed-time read-out in liquid crystal form on the display panel 8.

The illustrated timing device is such as to enable the rider himself to time a wheelie without the need for any operation of the control buttons either during or after the stunt, and also allows the rider to time himself accurately over a predetermined distance or course.

More particularly, the timer includes a movement-sensitive electric switch, conveniently a mercury tilt switch 5, which, with the housing 2 correctly angled on the handlebars 4 and with the bicycle in its normal horizontal orientation, is open circuit. A wheelie is carried out with the bicycle at a particular angle to the horizontal, and the orientation of the housing 2 and the tilt switch 5 therein relative to the handlebars 4 of the bicycle is chosen such that, in said wheelie position of the bicycle, the switch S closes to complete the electric circuit associated therewith. The precise orientation of the switch S within the housing 2 and relative to the handlebars 4 can be finely adjusted from externally of the housing by means of a grub screw (not shown) to ensure said closure.

The control button 10 can be rotated from a normal 'off' position, in which the supply voltage is disconnected from the timer circuitry, to a first operative position or wheelie mode 'W' enabling timing of a wheelie as will be detailed below, and thence to a second operative position or lap mode 'L' enabling timing of a predetermined distance or course again as will be described in more detail below.

The button 10 can also be depressed to reset the timer after the device has timed an event in either the wheelie mode or lap mode.

The control button 1 2 operates a pushbutton switch effective only with the button 10 in the lap mode position, initial depression of the button 1 2 with the button 10 in the 'L' position starting the timing counter and subsequent depression of said button 1 2 stopping the counter and resulting in an elapsedtime read-out being displayed on the panel 8 in liquid crystal form.

In order to time a wheelie, the following procedure is adopted. Prior to the stunt, the control button 10 is turned to the 'W' position which primes the circuit containing the mercury tilt switch S for completion. The bicycle is then raised onto its rear wheel only and, as soon as the wheelie position is achieved, the switch 8 is closed and the timing counter is switched on. At the same time, the display is blanked and remains blank throughout the stunt to avoid distraction to the rider. While the stunt is being performed. the counter remains operative. When the stunt is completed and the bicycle returns to its normal, two-wheels-on-the-ground position. the switch S is opened, the counter is stopped and an elapsed-time read-out is displayed on the panel 8 equivalent to the length of the wheelie.

Individual wheelies can be independently timed by pressing the button 10 to reset the timer between each two stunts, or. alternatvely, a cumulative time can be obtained by leaving the button 10 in the 'W' position and not depressing said button between the individual stunts.

Lap timing is effected by rotating the button 10 to the 'L' position which primes the counter for subsequent actuation by the button 1 2 and then depressing said button 1 2 at the start of the lap. A continuously changing readout of elapsed time is provided on the panel 8 until the lap is finished, when the button 1 2 is depressed again and the total time taken is displayed. Again, individual laps can be independently timed or cumulatively timed depending upon whether or not the button 10 is depressed to reset the timer between the laps.

The timing device may include a third mode of operation providing a real time read-out on the display panel, said mode being operative continuously and regardless of whether the button 10 is in the 'off', 'W' or 'L' positions.

Conveniently the device incorporates indicating means visible in the display panel 8 to show the particular mode of operation of the timer at any given time-for example a or an 'L' may appear in the panel 8 with the timer in the wheelie mode or lap mode respectively.

It is further preferred that the device incorporates a low battery indicator circuit which indicates when the output from the battery has fallen below a predetermined minimum level. Said indication is conveniently achieved by causing the display on the panel 8 to flash.

Referring to Fig. 3, the timing device is powered by a 9 volt battery and the circuitry includes a regulator R to step down the 9 volt supply to the particular requirements of the various integrated circuits. The liquid crystal display on the panel 8 is driven by a driver chip D which, in turn, is provided with regular pulses by an oscillator 0 arranged to sequence the display in seconds.

The control buttons 10 and 1 2 operate switches SW1 and SW2 respectively, and the circuitry includes a resistance -capacitance network RC arranged to prevent noise spikes caused by actuation of the switches SW1 or SW2 from producing a display on the panel 8. The circuitry further includes debounce circuits DB through which all other circuits pass such as to prevent bouncing in operation of the mercury tilt switch S from falsely triggering a display on the panel 8.

As mentioned above, the device incorporates a low battery indicator circuit LB which is such as to cause flashing of the display on the panel 8 if the battery powel level falls below that required to operate the device accurately.

The device may include means for illuminating the display panel 8 in the event of the bicycle being used in the dark. It will be appreciated that the electronic timer may be other than battery-operated and may be powered, for example, by a dynamo driven by the rear wheel of the bicycle or by a small solar panel. Other modifications and variations from the described arrangement will be apparent to those skilled in the art.

Thus there is provided a timing device for attachment to a BMX bicycle such as to enable the rider himself to time accurately a wheelie in a safe and convenient manner and which, if desired, has the added facility of enabling the rider to determine the time he takes to complete a predetermined course or lap.

Claims (11)

1. A timing device for a stunt bicycle comprises a housing for attachment to the bicycle and including an electronic timer provided with an elapsed-time display panel for viewing by a rider, the timer including a movement sensitive switching mechanism having a first condition associated with normal usage of the bicycle and a second condition effected with the bicycle at the particular angle to the horizontal associated with balanced movement on the rear wheel only, and manually-operated control means for actuating the timer, said control means being operable to switch the timer into a first mode of operation in which.

on displacement of the bicycle into the position for balanced movement on the rear wheel only, the timer is automatically started, and, on subsequent return of the bicycle to its normal position, the timer is automatically stopped, an elapsed-time read-out of the period during which the bicycle was in said displaced position being given on the display panel.

2. A timing device as claimed in claim 1 in which the display on the display panel is switched off during the period the bicycle is in the displaced position.

3. A timing device as claimed in claim 1 or claim 2 in which the control means are operable to switch the timer into a second mode of operation enabling subsequent controlled manual starting and stopping of the timer to give an elapsedtime read-out on the display panel of a period of standard riding of the bicycle.

4. A timing device as claimed in claim 3 in which the control means comprise a pair of button-operated switches the first of which can be moved from an off position to a first displaced position to switch the timer into its first mode of operation, and to a second displaced position to switch the timer into its second mode of operation, and the other of which switches enables said controlled starting and stopping of the timer when the first switch is in its second displaced position.

5. A timing device as claimed in claim 4 in which the first and second displaced positions ofthe first switch are effected by rotation of the associated button, depression of said button resulting in resetting of the display on the display panel to zero.

6. A timing device as claimed in claim 4 or claim 5 in which the other switch is pushbutton operated, alternate depressions of the associated push-button starting and stopping the timer when the first switch is in its second displaced position.

7. A timing device as claimed in any one of claims 1 to 6 in which the movement-sensitive switching mechanism includes a mercury tilt switch to effect the change from the first condition to the second condition.

8. A timing device as claimed in claim 7 in which the orientation of said switch relative to the housing is adjustable from external of the housing.

9. A timing device as claimed in claim 3 and all claims dependent therefrom in which the control means are operable to switch the timer into a third mode of operation providing a real time read-out on the display panel.

10. A timing device as claimed in any one of claims 1 to 9 and battery-operated, the device including means for indicating when the battery output has fallen below a predetermined minimum level.

11. A timing device as claimed in claim 3 and all claims dependent therefrom and including means in the display panel indicating the mode of operation of the device at any given time.

1 2. A timing device as claimed in any one of claims 1 to 11 in which aiÇ read-out displays on the panel are digital liquid crystal displays.

1 3. A timing device for a stunt bicycle substantially as described with reference to and as illustrated by the accompanying drawings.