FIELD OF INVENTION
The present invention relates to the field of electronics. More specifically it pertains to an electronic warning system for the vehicles moving on blind curves of the road.
BACKGROUND OF THE INVENTION
Since ages blind curves are one the major reasons for accidents on road. Blind curves are the curves or bends in the road which block our vision as we are driving. These are generally seen in hilly areas. They lead to major accidents because driver of a vehicle can not see the road as well as the oncoming vehicle from the opposite direction. The present invention pertains to a novel warning system for an oncoming vehicle from one side of the blind curve by providing a visual display in the form of signal light installed just after the other end of the blind curve. The driver of a vehicle coming from the opposite side can be aware of the oncoming vehicle on the blind curve by seeing this light and he can control the speed of his own vehicle to avoid accidents.
Patents relating to blind/ sharp curve detector existing in prior art:
A number of patents are available in the prior art which describe blind / sharp curve detectors for roads. However, none of them describes a detector of the type described in the present invention which comprises low cost, easy to install electronic system.
Patents of the prior art are discussed below:
Most of the patented techniques regarding blind curve detection are devices which are
generally needed to be installed in the vehicle itself and are discussed below:
US patent number 6,343,253 describes a device which needs to be installed in a vehicle to
calculate the accurate radius of the curvature. However, the present invention is for alerting
the driver of the vehicle about the coming vehicle in area of the blind curves in the form of
a glowing light fitted on the road just before the blind curve area.
US patent number 7,463,138 provides an imaging system for the vehicles which includes
an imaging sensor and a control in the vehicle. It works to project the image of the object
with in the target zone of the vehicles. The imaging system may be associated with a side

object detection system, a lane change assist system and a lane departure warning system.
However, the present invention does not involve any such complicated imaging system as
above.
US patent number 7,479, 897 provides an instrument with GPS system for detecting the
curves and road maps for the vehicles which are fitted in the vehicle. In contrast the present
invention is different from the above patent as GPS system is not included in it and the
system being used in the present invention is rather very simple and low cost. It does not
require any complicated GPS system operating through satellite.
US patent number7,522,747 describes an apparatus for detecting vehicle going in front
by using a camera image (from a camera fitted in vehicle itself) and detection data from a
radar for detecting position of the object in front of the said vehicle.
However, the present invention differs from the above as it does not require onboard
camera or electronic signal processor but uses only electrical/electronic signal to generate
indication in the form of glowing light on the road side and no equipment is installed in the
vehicle itself.
Patent number JP 2001006098 (A) provides an apparatus to improve accuracy in smooth
curve/sharp curve judgment in a curve detector forjudging whether a curve on the traveling
path of a vehicle is smooth or sharp.
However, the present invention differs from the above as it does not disclose any curve
sharpness detection system but only a curve detector system.
Patent number JP 11148394 (A) describes an instrument (vehicle controller) which needs
to be installed in vehicle to improve drivability under a narrow view road such as a blind
curve with the help of a controller which controls the vehicle according to the surrounding
conditions.
Patent number JP 2002312899 (A) describes an in vehicle support information system
with detectors to detect a vehicle moving in front as well as any other dangerous
conditions. This makes use of digital information processing system. However, the present
invention detects the vehicle coming from opposite direction on a blind curve with the help
of electrical /electronic signals and warns the vehicle driver in car by way of a blinking
light on the road side. No device is fitted as accessory in the vehicle.

Patent number JP 2005234999 (A) provides a drive support device for a vehicle, which realizes accurate obstacle recognition even in a blind intersection or a curve. The above patent consists of optical method of detection. This detector detects the picked-up images of the vehicle road reflected by the road mirror and recognizes its movement. In this apparatus the detector is installed in the vehicle itself and can function only where the mirror is provided on road. In contrast, the present invention does not require any on board vehicle apparatus and uses a metallic sensor fitted on road.
One more detector including camera is mentioned in patent number JP 2008052493 (A). It comprises an in vehicle apparatus with complex circuit configuration and equipment for confirming vehicle road condition including sharp curves. For this instrument to function, the roads must be provided with curved mirror so that camera installed in vehicle can detect upcoming road conditions. This apparatus includes electronic data processing to detect the road conditions. However, in the present invention all the equipments need to be provided on road, work on electrical/electronic/electronic signals, it is cheap and does not contain complex circuit configuration and is easy to install.
Patent number 101251955 (A) describes an on road equipment for detecting road sharp curve and electronic early warning device and method. It consists of two parts- a message processing and emitting device and a signal receiving, processing and displaying device which communicate with each other through radio signals. Both the parts need separate power supply units for functioning and thus the equipment required is more. However, in the present invention the system works on sensors and equipment required is less making it economical. It can work in adverse climatic conditions like snow fall, poor visibility and low temperature of the mountainous regions.
Patent number JP 2001283393 describes a system in which an array of lights is fitted at both the ends of blind curve on the road. It has two control systems and switching means to start or stop one of these controls. The system operates by taking a reference value of the speed of the vehicle which becomes a deciding factor for glowing of various lights. The visual display guides the driver of the vehicle to control his speed and pass safely through a blind curve. This system is designed for multiple vehicles entering the area. The system has

to be replicated along with the controls and array of lights on both the opposite sides of the blind curve for better safety. However, in the present invention the system installed on road has only one control and one light illumination system. Hence, switching system is not used to switch over from one control to another. Moreover the reference speed calculation is not required in the present invention. The timing for keeping the illumination ON is calculated for once before fitting the device on road. Although this system also needs to be installed on both sides of the curve yet because of its simplicity it gives a low cost safety solution.
From the above, it is clear that none of the prior art patents disclose a novel blind curve warning system of the type disclosed in the present invention.
Problems existing in the prior art patents: Most of the prior art patents include detectors
which need to be installed as complete assembly in vehicle or some part of such detectors
is installed in vehicle and the other part on road. Hence the application is restricted to the
vehicles fitted with such detector system and other vehicles devoid of such detectors are
unable to get the advantage. Also already existing detectors include complex circuit
configuration and high end equipments which are costly and require skill to manufacture
and install.
Further none of the prior art patents disclose any working circuit diagram which can be
tested for practical application by a person skilled in the art.
Hence there was a need to develop a system which is cost effective, rugged, easy to
maintain and need not be fitted in a vehicle, thus restricting its use.
OBJECT OF THE INVENTION
The invention has the following objects:
1. To disclose a blind curve detector system which can be installed on roads.
2. To disclose a blind curve detector system which need not be installed in vehicles
3. To disclose a system which is simple, low-cost and rugged

SUMMARY OF THE INVENTION
The present invention describes a cost effective electronic blind curve detector system which is fitted on both sides of the blind curve so that even an ordinary vehicle can be detected and can detect another vehicle coming from opposite direction whenever it passes over the sensor. The entire system is simply configured, easy to install and very cost effective.
DESCRIPTION OF DRAWINGS
Figure 01: It is a block diagram of the warning system for blind curve wherein SI, S2 are
sensors, CI, C2 are control units, LI, L2 are light emitting units. The sensor SI, control
unit CI and light emitting unit L2 are fitted on one end of the blind curve and the sensor
S2, control unit C2 and light emitting unit LI are fitted on the other opposite end of the
blind curve. Both the systems have separate power supply units.
Figure 02: It is a diagrammatic representation of blind curve on the road with the present
warning system wherein VI, V2 are vehicles approaching from the blind curve region from
opposite directions.
Figure 03: It is a block diagram of the model circuit of the warning system for blind curve
wherein the blocks represent the following units:
Block A- Bridge rectifier comprising of step down transformer (1), diode bridge IN 4007
(2)
Block B- Relay unit (15)
Block C- Flasher unit comprising of IC LM324 (19), Resistor IK (5), Variable resistor 100
K (10), Capacitor 100 Micro Farad (8), Capacitor 0.1 Micro Farad (9)
Block D- Timer unit comprising of NE 555, Resistor IK (5), Variable resistor 100 K (10),
Capacitor 100 Micro Farad (8), Capacitor 0.1 Micro Farad (9)
Block E- Sensor unit comprising of Resistor 220 K (11), Resistor 330 K (12), Variable
Resistor 500 K (13), IC LM 324(14) and Light emitting Diode 3 Volt (6)
Block F- Display unit comprising of LED/ Bulb/ any other illuminating device (16)
The sensor to be used can be commonly available bimetallic / photo transistor (17) /
infrared (18) sensor which give signal to Block E for further processing.

DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to an electronic blind curve warning system. It warns the driver of a vehicle on the blind curve by detecting the vehicle coming from opposite direction with the help of electrical signals and glowing / blinking lights on the road side. The circuit is very simple in configuration and easy to install. It facilitates the driver of a vehicle to avoid accidents on the blind curve without any inbuilt navigation system in his vehicle.
NOVELTY ASPECT OF INVENTION: The present invention describes a warning system for blind curve which can be installed on road. Most of the detector systems present in the prior art are partly or fully needed to be installed in vehicle to receive and process the signal of a navigation system without disclosing the circuit diagram for actual practical application testing. However, in present system none of the equipments are needed to be installed in vehicle. Rather, it is simple in circuit configuration and to the best of knowledge of the inventor has not been disclosed anywhere in the prior art. The inventor has described a fully workable circuit in form of example.
INDUSTRIAL APPLICATION: The components and parts required for the system of the present invention are easily available commercially. Hence the invention can be easily manufactured by standard industrial processes to produce blind curve warning systems. Such systems can be best utilized in hilly and mountainous regions where blind curves pose a continuous threat for accidents.
Warning system for blind curve detection: Warning system for blind curve detection of the present invention is a complete system which detects an oncoming vehicle with the help of a bimetallic sensor block (fitted in the road), a control block (having power supply, relay, flasher, timer unit) and a display block (with a light emitting device.)
The sensor SI, control unit CI and a glow light system L2 are all fitted on one end of the road approaching the blind curve (Figure 2). The sensor S2, control unit C2 and a glow light system LI are fitted on the opposite direction of the road and at the other end of the

blind curve (Figure 2). When a vehicle approaches a blind curve, it has to pass over the bimetallic sensor (Figure 2). This sensor generates a signal for control block which processes it. According to Figure 3, the relay is initiated through its NO (normally open) control and the circuit from the power supply is completed. The 12V DC from the transformer is connected to the timer unit through relayRl. The timer is used to set a particular time for which the light on the road side keeps on glowing after the vehicle passes over the sensor. The timer NE555 can be set with the help of timer unit comprising of a combination of resistors and capacitors as shown in Figure 3. The output of the timer is used to generate signal for the flasher unit which in turn illuminates the lighting system which may be a LED, a bulb or any other glowing / blinking device. The whole system can be worked out on 220V AC power supply also and the 12V DC power supply is not a limiting factor for the person skilled in the art.
EXAMPLE : Figure 01: A vehicle VI approaches the blind curve BC1 passing over the sensor SI. The control unit CI triggers the circuit as explained above and a light emitting system L2 is set ON. This remains ON for a time predetermined and set through timer on the basis of average timing needed by the vehicle to cross the blind curve region and come in view of the vehicle coming from the opposite direction. On the other hand when a vehicle V2 approaches the blind curve BC2 passing over the sensor S2,the control unit C2 triggers the circuit as explained above and a light emitting system LI is set ON. It also remains ON for a time predetermined as explained above.
Case 1: At a time Tl, a vehicle VI passes over the sensor from one end of the curve, the light LI remains ON and the driver of the vehicle V2 at the other end will immediately be aware of its entering the dangerous area and he will be cautious enough to speed down his own vehicle. This applies for the vehicle driver of vehicle VI too.
Case 2: when a vehicle VI has already passed over the sensor at the time Tl and no other vehicle is coming from the opposite direction, the light LI will be glowing for a preset time but L2 will not be glowing. If at any other time say T2, another vehicle V2 enters the blind curve from the other direction, the light L2 starts glowing but the driver of the vehicle VI

will not be able to see the light L2 which he has already crossed considering it being OFF
as no vehicle was entering at time Tl . Driver of vehicle VI will not control the speed of
his own vehicle. But at the same time, since the light LI is ON till he crosses the blind
curve, the driver of the vehicle V2 will be duly aware of its presence on the curve as he can
see the light LI ON even before entering the blind curve area. He can avoid the collision by
controlling the speed of his own vehicle.
As shown above in two cases, since one of the drivers of either of the vehicles will always
get an indication of the oncoming vehicle from the other direction, head-on collision of the
vehicles is avoided.
Thus the warning system helps avoid accidents and functions as a simple safety device.
The above examples are only illustrative in nature. Once the basic concept is understood, it will be clear to those skilled in the art that deviations from the disclosures made herein are possible. These should be regarded as within the scope of the invention.
In the preceding detailed description, the invention is described with reference to specific exemplary embodiments thereof. Various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention as set forth in the claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense. Thus, without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention.

I CLAIM:
1) A warning system for blind curve on road wherein the same comprises of
- a sensor block
- a control block having power supply, relay, flasher and timer unit as its components and
- a light emitting block
all installed in / on the road on both ends of the blind curve respectively.
2) The system as claimed in claim 1 wherein the sensor block is any suitable sensor such as bimetallic sensor or optical sensor or infrared sensor.
3) The system as claimed in claim 1 wherein the control block power supply is either 12V DC power supply or 220V AC .
4) The system as claimed in claim 1 wherein the control block timer unit is a electronic timer.
5) The system as claimed in claim 1 and claim 4 wherein the timer unit is a pre-set timer.
6) The warning system for blind curve on road as claimed in claim 1 wherein the light emitting unit comprises suitable light source such as LED (light emitting diode), bulb or any other glowing / blinking device, a glowing / blinking number, or shape or a combination thereof.
7) The warning system for blind curve on road as claimed in claim 6 wherein the light emitting unit can use any color and luminosity value.
8) A warning system for blind curve on road as substantially described herein with reference to the detailed description.