GB2244195A

GB2244195A - Bite detectors

Info

Publication number: GB2244195A
Application number: GB9009791A
Authority: GB
Inventors: Peter John Forward
Original assignee: Individual
Current assignee: Individual
Priority date: 1990-05-01
Filing date: 1990-05-01
Publication date: 1991-11-27
Also published as: GB9009791D0

Abstract

A bite detector for use with a fishing rod comprises a housing 1 incorporating a Piezzo electric transducer 3 with generates output signals when the transducer is vibrated. These signals may go to an alarm or the like. The Piezzo electric transducer 3 consists of an elongate element Piezzo electric material, one end of which is mounted securely to the housing, and the other end extends freely in a cantilevered manner so that it can readily vibrate. <IMAGE>

Description

DESCRIPTION OF INVENTION "Improvements in or relating to a Bite Indicator" THE PRESENT INVENTION relates to a bite indicator and more particularly relates to a bite indicator intended for use in conjunction with a fishing rod.

It has been proposed previously to provide a bite indicator for use with a fishing rod, the bite indicator responding to an increase in tension in the fishing line.

Whilst such a bite indicator may be of value for fresh-water fishermen, such a bite indicator is not of significant value for sea fishermen. The present invention seeks to provide an improved bite indicator.

According to one aspect of this invention there is provided a device for use with a fishing rod, the device comprising a housing incorporating a Piezzo electric transducer, and means to respond to vibrations sensed by the Plezzo electric transducer, the Piezzo electric transducer comprising an elongate element of Piezzo electric material, mounted to a fixing point on the housing at one end and extending freely from the said fixing point.

Preferably a weight is provided at the free end of the element of Piezzo electric material, so that the weight is supported in a cantilevered fashion by the Piezzo electric material.

According to another aspect of this invention an arrangement for sensing vibration in a fishing rod, the arrangement comprising a housing, the housing containing a Piezzo electric transducer adapted to respond to vibrations in the fishing rod, the output of the Piezzo electric transducer being processed and being fed to a comparator where the output is compared with a reference, the arrangement further including alarm means adapted to be activated when the signal exceeds the reference.

The alarm may be an audible alarm, such as a buzzer, or a visible alarm, such as a flashing light emitting diode.

Preferably the output of tht transducer is filtered and is then converted to a voltage, the voltage being compared with a reference voltage.

Conveniently the means effecting the comparison of the voltage with the reference voltage incorporate a latch so that when the voltage exceeds the reference voltage the latch is operated, the latch activating the alarm.

Advantageously switch means are provided adapted to re-set the latach to the initial condition.

Preferably the reference is adjustable.

Conveniently switch means are provided adapted to provide a predetermined reference.

Preferably the Piezzo electric transducer com- prises an elongate element mounted to a fixing point on the housing and extends freely from the said fixing point.

In order that the invention may be more readily understood, and so that further features thereof may be appreciated, the invention will now be described, by way of example, with reference to the accompanying drawings in which FIGURE 1 is a diagrammatic view of a Piezzo electric transducer forming part of a bite indicator in accordance with the invention, FIGURE 2 is a block diagram of the electric circuitry associated with the Piezzo electric transducer, and FIGURES 3 and 4 together form a circuit diagram of the arrangement illustrated in block diagram form in Figure 2.

Referring initially to Figure 1 a bite indicator in accordance with the invention comprises a housing 1 adapted to be mounted on the fishing rod 2. The housing may be connected to the fishing rod in any convenient way and may indeed be formed integrally with the fishing rod. The housing contains a Piezzo electric transducer of the form illustrated in Figure 1. The Piezzo electric transducer is of the form of an elongate plate or strip 3 of Piezzo electric material which projects from a support, which forms an integral part of the housing. Thus one end of the strip is fixably monted to a fixing point on the housing.At the end of the strip of the Piezzo electric material projecting away from the support is a weight or mass 4. Thus the Piezzo electric material itself supports the weight, and the weight is thus effectively cantilevered by the Piezzo electric material. The Piezzo electric material is provided, as is conventional, with opposed electrodes 5,6 on which a signal is present when the Piezzo electric material is deformed.

It will be appreciated that when a vibration is present in the rod, the vibration will be transferred directly to the housing and thus to the Piezzo electric strip 3 which will then vibrate. The vibration of the Piezzo electric strip will be enhanced by the presence of the cantilevered weight 4. Thus the Piezzo electric transducer will provide an output signal on the electrodes 5,6 whenever a vibration is detected.

Turning now to Figure 2 of the drawings, the Piezzo electric transducer 3 is illustrated, and it is to be appreciated that it is in the very nature of Piezzo electric material that it operates as a high-pass filter. The output of the Piezzo electric transducer is fed to a low-pass filter 7 which can be embodied by a high-gain amplifier which amplifies low frequency signals. The output of the low-pass filter is fed to a frequency to voltage conversion circuit 8. The output voltage from the frequency to voltage conversion circuit is fed to a comparator and latch arrangement 9. The voltage is effectively compared with a reference voltage from the reference source 10, and when the reference voltage is exceeded, the circuit latches. The circuit, when latched, can activate an audio indicator 11 such as a buzzer and a visiual indicator, such as a flashing light 12.There is a re-set timer circuit 13 which will re-set the arrangement to its initial condition after a predetermined period of time.

Figures 4 and 5 illustrate the circuit diagram in more detail. The Piezzo electric transducer 3, has output electrodes 5,6. The electrode 6 is connected to the ground rail 14, the electrode 5 is connected to one input of a high-gain operational amplifier 15. The electrode 5 is connected to the negative input of the amplifier 15 and the output of the amplifier 15 is connected by means of a resistor 16 in parallel with a capacitor 17, to the negative input thereof. This provides a negative feed-back to assist in maintaining the stability of the amplifier. The positive input of the amplifier 15 is connected to a node 17 established between two resistors 18,19 which are connected in series between the positive rail 20 and the ground rail 14. Thus effectively a constant reference voltage is applied to the positive input of the amplifier 15.The amplifier 15 is a high-gain amplifier which amplifies low frequency signals, but which does not amplify high frequency signals which may, for example, be caused by the effect of wind. If high frequency signals are applied to the input they give rise to a strong negative feed-back through the capacitor 17. The output of the amplifier 15 is 4.5V in quiescent conditions, and swings between 0 and 9 V when a signal is generated by the trasnsducer 3.

The output of the amplifier 15 is connected by means of a diode 21 to a node 22 which is connected by means of a capacitor 23 in parallel with a resistor 24 to the positive rail 20. The capacitor 23 will tend to charge up through the resistor 24 and will discharge through the diode 21 when the signal at the output of the amplifier 15 is low. The end result is that when a large signal is generated by the Piezzo electric transducer 3, a steady DC signal is generated at the node 22 which is substantially zero volts. However, when no signal is generated by the transducer, the potential of node 22 rises to be substantially 4.5 volts, which is the potential present at the output of the amplifier 15.

In an intermediate state of valuation an intermediate voltage will be present at the node 22.

The node 22 is connected to the negative input of a further amplifier 25. The positive input of the amplifier 25 is again connected to the reference voltage present at node 17. The amplifier 25 simply acts as an inverting power amplifier and thus while the input to this amplifier is between 0.4.5 volts the output Is between 9 and 4.5 volts respectively.

The output of the amplifier 25 is connected to a node 26 which is connected to a further node 27 by a high value resistor 28 which has connected in parallel with it a diode 29 and a low value resistor 30 in series. The node 27 is connected, by means of a capacitor 31 to the ground rail 14. It is to be noted that the resistor 28 has a much higher value than the resistor 30. When a relatively hgih voltage is present on the node 26, the capacitor 31 is charged up through the resistance 28. When a low voltage is present at the node 26, which is lower than the voltage on node 27, the capacitor 31 will discharge, through the diode 29 and the resister 30. The capacitor will discharge relatively swiftly, because of the low value of the resistance 30. Thus the signal at node 27 is effectively the invert of the signal present at the node 22.

The node 27 is connected to the positive input of a further amplifer 32, the negative terminal of which is connected to a node 33 which is connected by a resistance 34 to the ground rail 14. The node 33 is also connected, by means of a resistance 35 to a further node 36 which is connected to the output of the amplifier 32. The amplifier 32 acts to amplify and buffer the signal. When a signal is generated by the Piezzo electric transducer 3 the output of the amplifier 32 is a rising voltage, which drops quickly when the signal is no longer generated by the transducer 3.

The node 36 is connected by means of a resistance 37 to a further node 38 which is connected to the positive input of a further amplifier 39. The negative input of the amplifier 39 is connected to a node 40. The node 40 is connected to a tap 41 contacting a resistance 42 which is connected between the positive rail 20 and the ground rail 14. Thus, a voltage is applied to the negative terminal of the amplifier 39 dependent upon the position of the tap 41 on the resistance 42. The tap 41 is also connected, by means of the series connection of a resistance 43 and a switch 44 to the ground rail 14. The switch 44 may be closed, thus applying a different potential to the node 40.

This effectively alters the sensitivity of the device.

Thus this potential may be used, for example, when there is calm weather.

The node 40 is also connected by means of a switch 45 to the positive rail 20. The amplifier 39 forms part of a latch circuit and operation of the switch 45 will effectively pull a reference voltage applied to the latch circuit, at node 40, to a high potential, thus setting the latch low. When the switch 45 is closed a positive voltage is applied to hte negative input of the operational amplifier 39, this positive voltage being greater than the positive voltage applied to the positive input.

The output of the amplifier 39 is fed to a node 46. The node 46 is connected by means of a feed-back resistor 47 to the node 38. It is also connected by means of a parallel connection of a diode 48 and a resistance 49 to a node 50 which is connected to the base of a transistor 51, a collector of which is connected to the positive rail 20 and the emitter of which is connected to the node 41. The node 50 is also connected by means of a capacitance 52 to the ground rail 14. It will be appreciated that when the output of the amplifier 39 goes high, the high signal is passed through the resistance 49, charging up the capacitance 52, thus bringing the base of the transistor 51 high, switching on the transistor 51. Because the transistor 51 is switched on, the node 41 moves high and thus the latch is in the latched condition.When the latch is re-set by the switch 45 the output of the amplifier 39 goes low and the capacitor 52 discharges through the diode 48. The latch, of course, effectively compares the input signal at node 38 with the reference signal at node 40 and only operates when the signal at node 38 exceeds the voltage present at node 40.

An output signal, from the node 46, is passed to an oscillator consisting of two serially connected NAND gates, the first gate being provided with a feed-back resistor 54 and also having one terminal connected by means of a capacitor 55 to the earth rail 14.

The output of the second gate 53 is connected to a light-emitting diode 56 which in turn is connected by means of a resistance 57 to the earth rail 14. The oscillator causes the light-emitting diode 56 to flash and emit light.

The input node 46 is also connected by means of a capacitance 58 to one input of a further NAND gate 59, that input of the gate also being connected, by means of a resistance 60, to the ground rail. The gate 59 enables a buzzer circuit, formed by further NAND gates 60, and 61, which has a feed-back resistance 62 connected to a terminal thereof, that terminal also being connected by means of a capacitance 63 to the ground rail 14. The output of the NAND gate 61 is connected to a further serial connection of two NAND gates 62,63 which are connected in parallel with a serial connection of a further NAND gate 64 and a Piezzo transducer 65 to a parallel connection of a resistance 66 and a switch 67. These components comprise a buzzer circuit, the switch 67 being operable to provide the buzzer with an adjustable amplitude or volume.

It is to be appreciated that the four amplifiers shown in Figure 4 may be embodied by a single integrated circuit LP324 and the various gates present in the circuit as illustrated in Figure 5 may be implemented by a single circuit 4093.

Claims

CLAIMS:

1. A device for use with a fIshIng rod, the device comprising a housing incorporating a Piezzo electric transducer, and means to respond to vibrations sensed by the Piezzo electric transducer, the Piezzo electric transducer comprising an elongate element of Piezzo electric material, mounted to a fixing point on the housing at one end and extending freely from the said fixing point.

2. A device according to Claim 1 wherein a weight is provided at the free end of the element of Piezzo electric material, so that the weight is supported in a cantilevered fashion by the Piezzo electric material.

3. An arrangement for sensing vibration in a fishing rod, the arrangement comprising a housing, the housing containing a Piezzo electric transducer adapted to respond to vibrations in the fishing rod, the output of the Piezzo electric transducer being processed and being fed to a comparator where the output is compared with a reference, the arrangement further including alarm means adapted to be activated when the signal exceeds the reference.

4. An arrangement according to Claim 3 wherein the alarm is an audible alarm.

5. An arrangement according to Claim 4 wherein the alarm is a buzzer.

6. An arrangement according to Claim 3 wherein the alarm is a visible alarm.

7. An arrangement according to Claim 4 wherein the alarm is a flashing light emitting diode.

8. An arrangement according to any one of Claims 3 to 7 wherein the output of the transducer is filtered and is then converted to a voltage, the voltage being compared with a reference voltage.

9. An arrangement according to Claim 8 wherein the means effecting the comparison of the voltage with the reference voltage incorporate a latch so that when the voltage exceeds the reference voltage the latch is operated, the latch activating the alarm.

10. An arrangement according to Claim 9 wherein switch means are provided adapted to re-set the latch to the initial condition.

11. An arrangement according to any one of Claims 8 to 10 wherein the reference is adjustable.

12. An arrangement according to Claim 11 wherein switch means are provided adapted to provide a predetermined reference.

13. A vibration sensor for use with a fishing rod substantially as herein described with reference to and as shown in the accompanying drawings.

13. An arrangement according to any one of Claims 3 to 12 wherein the Piezzo electric transducer comprises an elongate element mounted to a fixing point on the housing and extends freely from the said fixing point.

14. An arrangement according to Claim 13 wherein a weight is provided at the free end of the element of Piezzo electric material so that the weight is supported in a cantilevered fashion by the Piezzo electric material.

15. A vibration sensor for use with a fishing rod substantially as herein described with reference to and as shown in the accompanying drawings.

16. Any novel feature or combination of features disclosed herein.

AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWS 1. A bite-sensing device for use with a fishing rod, the device comprising a housing, there being a Piezo electric transducer contained within the housing, the Piezo electric transducer comprising an elongate element of Piezo electric material, mounted to a fixing point on the housing at one end and extending freely from the said fixing point within the housing, means being provided to mount the housing on the fishing rod so that vibrations in the rod will be transferred to the transducer, and means being provided to respond to vibrations sensed by the Piezo electric transducer.

2. A device according to Claim 1 wherein a weight is provided at the free end of the element of Piezo electric material, so that the weight is supported in a cantilevered fashion by the Piezo electric material.

3. An arrangement for sensing vibration in a fishing rod, the arrangement comprising a device according to Claim 1 or 2, means being provided to process the output of the Piezo electric transducer and to feed the resultant processed output signal to a comparator where the processed output signal is compared with a reference, the arrangement further including alarm means adapted to be activated when the signal exceeds the reference.

4. An arrangement according to Claim 3 wherein the alarm is an audible alarm.

5. An arrangement according to Claim 4 wherein the alarm is a buzzer.

6. An arrangement according to Claim 3 wherein the alarm is a visible alarm.

7. An arrangement according to Claim 4 wherein the alarm is a flashing light-emitting diode.