WO2003079311A1

WO2003079311A1 - System for traffic signals and traffic passing at intersections

Info

Publication number: WO2003079311A1
Application number: PCT/KR2002/000985
Authority: WO
Inventors: Duk Kyu Choi
Original assignee: Duk Kyu Choi
Priority date: 2002-03-15
Filing date: 2002-05-24
Publication date: 2003-09-25
Also published as: AU2002303007A1

Abstract

The present invention relates to a new system for traffic signals and passing traffic at intersections, which may shorten the cycle and periods for passing the traffic and passengers. The system is characterized by that the smallest traffic volume at the four directions roads make a right turn and U-turn thereafter in a certain point, not permitting to drive straight and to make a left turn. At an intersection where four directions roads A, B, C and D meet and where the two roads A and B have more traffic volume than the two roads C and D, the system of the present invention carries out one cycle to pass all the traffics from four directions roads at the intersection, and the cycle consists of three periods.

Description

SYSTEM FOR TRAFFIC SIGNALS AND TRAFFIC PASSING AT INTERSECTIONS

Field of the Invention

The present invention relates to a system for traffic signals and passing traffic at intersections. More particularly, the present invention relates to a new system for traffic signals and passing traffic at intersections, which may shorten the cycle and periods for passing the traffic and passengers.

Background of the Invention

A conventional system for passing the traffic has been applied at intersections where two roads are crossed or where five directions roads are met. For example, at an intersection with two roads, the traffic at each direction is mostly allowed to drive straight and to make a left turn. Of course, the traffic at each direction can freely make a right turn almost anytime. Accordingly, it is said that each direction road has a passage rate of 25 % in terms of time of passing through the intersection normally. In other words, the traffic at each direction road should wait for time of 75 % to pass through the intersection. Accordingly, heavy traffic jam occurs at intersections all the time.

At some intersections, the left turn at each direction road is not allowed in order to improve the passage rate of the passing through traffic. In this case, the passage rate of the passing through traffic at two roads increases up to 50 %. However, such system is not good all the time. Because the traffic intended to make a left turn should detour to arrive at the final destinations.

In order to solve the heavy traffic jam at intersections, an underpass way or an overpass way can be built. Although both underpass and overpass operate good to solve the traffic jam, it costs tremendous to build them, and the circumstance around the construction becomes worse in terms of appearance.

The present inventor has developed the present system for traffic signals and passing traffic at intersections, which may shorten the cycle and periods for passing the traffic and passengers, without building an underpass or an overpass at intersections.

Objects of the Invention

A feature of the present invention is the provision of a system for traffic signals and passing traffic at intersections, which may shorten the cycle and periods for passing the traffic and passengers.

Another feature of the present invention is the provision of a system for traffic signals and passing traffic at intersections, which may shorten the cycle and periods for passing the traffic and passengers, without building an underpass or an overpass at intersections.

A further feature of the present invention is the provision of a system for traffic signals and passing traffic at intersections, which may shorten the cycle and periods for passing the traffic and passengers, reducing car accidents and driving very safely.

Other objects and advantages of this invention will be apparent from the ensuing disclosure and appended claims.

Summary of the Invention

The system for traffic signals and passing traffic at intersections, according to the present invention, is characterized by that the smallest traffic volume at the four directions roads make a right turn and U-turn thereafter in a certain point, not permitting to drive straight and to make a left turn.

More specifically, as shown in Fig. 1, at an intersection where four directions roads A, B, C and D meet and where the two roads A and B have more traffic volume than the two roads C and D, the system according to the present invention carries out one cycle to pass all the traffic from four directions roads at the intersection, and the cycle consists of three periods. In the conventional systems, one cycle consists of four periods to pass all the traffic from four directions roads at the intersection. Therefore, the present system can reduce the traffic jam at intersections, because one cycle consists of three periods rather than four periods. During the first period of the present invention, the traffic on road A and the traffic on road B pass through the intersection simultaneously. During the first period, the traffic on roads A and B to intend to make a left turn should wait, and the traffic is called "left turn traffic" hereinafter.

During the second period, the left turn traffic on roads A and B make a left turn. And, both the left turn traffic on road D and the drive straight traffic on road D make a right turn simultaneously for U-turn at a certain point on road A, which are called "U-turn traffic" hereinafter.

During the third period that is final in one cycle, the traffic on road C drives straight and makes a left turn simultaneously, and the U-turn traffic keeps U-turning. The three periods are repeated in order.

In the present invention, double traffic signals are installed at a distance of about 70 to about 150 meters on road A for the U-turn traffic to make a U-turn freely and safely. The double signals consist of signal S₃ being installed at the intersection and signal Sj around the U-turn point on road A. Therefore, the present invention is called "Double Signal System".

Brief Description of the Drawings

Fig. 1 is a schematic plan view of an intersection for implementing the system for traffic signals and passing traffic according to the present invention;

Fig. 2 is a schematic front view of a signal for U-tum to install at the U-turn point for implementing the system for traffic signals and passing traffic according to the present invention; and Fig. 3 is a schematic rear view of the signal for U-turn of Fig. 2.

Detailed Description of the Invention

The present invention relates to a new system for traffic signals and passing traffic to reduce traffic jam at intersections, by shortening the cycle and periods for passing the traffic and passengers.

Fig. 1 is a schematic plan view of an intersection for implementing the system for traffic signals and passing traffic according to the present invention. As shown in Fig. 1 , in order to apply the present system to an intersection, the main road should have at least three lanes per way, because the main road should have enough space for the U-turn traffic to U-turn with no difficulty. Thus, if the main road has one or two lanes, it is almost impossible to implement the present system at the intersection. In this application, the main road means the road that has more traffic volume than the other road. In Fig. 1, the main road consists of roads A and B. Although the two roads to be crossed have almost same traffic volume, the system of the present invention can be properly implemented.

As shown in Fig. 1 , the double signal system according to the present invention is carried out by installing double signals on road A, which are operated together. If one set of the double signals is installed on the main road, one cycle for passing all the traffic at the intersection consists of three periods. And, if two sets of the double signals are installed on the main road, on roads A and B, one cycle for passing all the traffic at the intersection consists of two periods. In the conventional system, one cycle for passing all the traffic at the intersection consists of four periods normally. Therefore, the present system can reduce the time of cycle for passing all the traffic from four directions at the intersection, and the waiting time of waiting traffic, and finally traffic jam.

In the system of Fig. 1, one set of the double signals is installed on road A only, thus one cycle becoming three periods. During the first period in Fig. 1, the traffic on road A and the traffic on road B pass through the intersection simultaneously. During the first period, the traffic on roads A and B to intend to make a left turn should wait for next signal. During the first period, traffic signals S₃, S₅ and Si only keep green lights.

When the first period is ended, signals S₃, S and Si turn on red lights at the same time. Then, signals S₄, S₆ and S turn on green lights and the second period begins. Signal Sι₀ turns on green lights at the same time as signals S₄, S₆ and S₉. Signals S and S₆ are displayed with left arrow lights (π) as in the conventional system and signal S₉ is preferably displayed with bias arrow lights (for example D). During the second period, the left turn intended traffic on roads A and B make a left turn. And, both the left turn intended traffic on road D and the drive straight intended traffic on road D make a right turn simultaneously for U-turn at a certain point on road A.

When the second period is ended, signals S₄, S₆ and S₉ turn on red lights at the same time. Then, signals S₇ and S₈ turn on green lights and the third period begins. During the third period, the traffic on road C drives straight and makes a left turn simultaneously, and the U-turn traffic keeps U-turning. During the third period, signal Sι₀ keeps green lights. The three periods are repeated in order. When next first period begins, signals S₇, S₈ and Sι„ turn on red lights at the same time. Then, signals S₃, S₅ and Si turn on green lights. In the present invention, double traffic signals are installed at a distance of about 70 to about 150 meters on road A for the U-turn traffic to make a U-turn freely and safely. The double signals consist of signal S₃ being installed at the intersection and signal Si around the U-turn point on road A. The distance between the double signals can be determined on the length of the cue of the left turn traffic on road A and the time for the traffic to make a left turn. Preferably the left turn traffic on road A has to turn left during the second period. In certain circumstances, the distance may be shorter than 70 meters.

Around the U-turn area on road A, there should be empty space for the U-turn traffic to U-turn, because the double signals Si and S₃ turn red at the same time. The U-turn traffic can U-turn with no blocking traffic at the T-turn area. The U-turn traffic has enough time to U-turn, even if the traffic starts from road D. The time for the U-turn traffic to U-turn is the sum of the first period and the second period.

For the U-tum traffic to U-turn more smoothly at the U-turn area and after U-turn, an additional lane AL may be preferably provided, if possible. Although the U-turn traffic has enough time to U-turn, the drivers of the

U-turn traffic may feel dangerous during driving from road D via the U-turn area to the safe area on road A. They may worry about how much time left for making U-turn at the U-turn area. Therefore, the U-turn signals Sι₀ are installed at the U-turn area like in Fig. 1. Thus, the U-turn signals function as an indicator lights to assure the drivers that enough time to U-turn still exists. The U-turn lights are specially designed for the purpose of the present invention.

Fig. 2 is a schematic front view of a signal for U-turn to install at the U-turn point for implementing the system for traffic signals and passing traffic according to the present invention, and Fig. 3 is a schematic rear view of the U-turn signal. The U-turn light consists of a red light 1, a green light 2 and indicator lights 3.

When signal Sj turns red, the U-turn light turns on the green light 2. The green light 2 turns on for the second period and the third period. When the third period begins, the indicator lights 3 turn on green. Passing the third period, the indicator lights turn off in a row, and the last indicator light turns off when the third period is finished. The drivers of the U-turn traffic can see the indicator lights and do not have to hurry up to make a U-turn. The U-turn traffic can drive absolutely safe. The U-turn lights are installed at the U-tum point for the drivers of the U-turn traffic to see the red light 1, green light 2 and indicator lights 3. However the drivers of the waiting traffic in front of the signal S have to see the indicator lights 3 only, because the red light 1 and green light 2 may cause confusion to the drivers sometimes. In the system of Fig. 1, three crosswalks P_l5 P₂ and P₃ may be operated very safely. In the conventional system at intersections, mostly there are four crosswalks. However, the waiting time of passengers at intersections may be shorten in the present invention. The double signal system according to the present invention can be modified depending on the circumstances of the intersection. Two sets of the double signals can be implemented at an intersection. In this case, one cycle consists of two periods only. Referring to Fig. 1, the second set of double signals can be installed on road B. In such system, during the first period, the traffic on road A and the traffic on road B pass through the intersection simultaneously, and during the second period, the left turn traffics on roads A and B make a left turn, and both the left rum traffic on road D and the drive straight traffic on road D make a right turn simultaneously for U-turn on road A, and both the left rum traffic on road C and the drive straight traffic on road C make a right turn simultaneously for U-turn on road B. In the system of Fig. 1, if the straight traffic volume on road C is smaller than the left turn traffic volume on road C, the left turn traffic on road D can be passed stopping the straight traffic on road C during the third period.

The double signal system according to the present invention can be applied to an intersection where five or six directions roads meet. If two sets of the double signals are installed at an intersection with five directions roads, one cycle can consist of three periods. In such system, during the first period, the traffic on the main road (roads A and B) passes through the intersection simultaneously, and during the second period, the left turn traffics on roads A and B make a left turn, and both the left turn traffic on road D and the drive straight traffic on road D make a right turn simultaneously for U-tum on road A, and both the left turn traffic on road C and the drive straight traffic on road C make a right turn simultaneously for U-tum on road B, and during the third period, the traffic on road E (not shown) drives straight and makes a left turn simultaneously, and the U-tum traffics keep U-tuming on roads A and B. For an embodiment of the system shown in Fig. 1 , the first period will be 60 seconds, the second period 30 seconds, and the third period another 30 seconds. Each period can be controlled depending on the traffic volume at each direction.

The present system will be a revolutionary invention to save time, energy and money to human beings in this world.

The present invention can be easily carried out by an ordinary skilled person in the art. Many modifications and changes may be deemed to be with the scope of the present invention as defined in the following claims.

Claims

What is claimed is:

1. A system for traffic signals and passing traffics at an intersection with four directions roads A, B, C and D, comprising: during the first period, passing the traffic on road A and the traffic on road B through the intersection simultaneously; during the second period, allowing the left rum traffic on roads A and B to make a left rum, and allowing both the left turn traffic on road D and the drive straight traffic ("U-turn traffic") on road D to make a right turn simultaneously for U-turn on road A; and during the third period, passing the traffic on road C straight and to the left simultaneously, and allowing said U-turn traffic to keep U-turning; wherein double signals are installed at a distance of about 70 to about 150 meters on road A for said U-turn traffic to make a U-tum freely and safely, and the double signals consist of signal S₃ being installed at the intersection and signal S_x around the U-turn point on road A.

2. The system as defined in claim 1, wherein said roads A and B have more traffic volume than roads C and D.

3. The system as defined in claim 1, wherein said roads A and B have at least three lanes per one way.

4. The system as defined in claim 1 , wherein said U-tum point is installed with U-tum signal Sι₀.

5. The system as defined in claim 4, wherein said U-tum signal consists of a red light 1, a green light 2 and indicator lights 3 and is installed for the drivers of the U-turn traffic to see the red light 1, green light 2 and indicator lights 3 and for the drivers of the waiting traffic in front of the signal S_x to see the indicator lights 3 only.

6. The system as defined in claim 1, wherein said U-tum traffic starts to drive upon signal S₉ to be displayed with bias arrow light.

7. The system as defined in claim 1, further comprising an additional lane AL for the U-turn traffic to U-tum more smoothly at the U-tum area and after U-turn.

8. The system as defined in claim 1, further comprising three crosswalks Pi, P₂ and P₃ for passengers.

9. A system for traffic signals and passing traffics at an intersection with four directions roads A, B, C and D, comprising: during the first period, passing the traffic on road A and the traffic on road B through the intersection simultaneously; and during the second period, allowing the left turn traffic on roads A and B to make a left turn, and allowing both the left turn traffic on road D and the drive straight traffic on road D to make a right rum simultaneously for U-tum on road A, and allowing both the left turn traffic on road C and the drive straight traffic on road C to make a right rum simultaneously for U-turn on road B, wherein two sets of double signals are installed at a distance of about 70 to about 150 meters on roads A and B for said U-turn traffic to make a U-turn freely and safely, and one set of the double signals consist of signal S₃ being installed at the intersection and signal Si around the U-tum point on road A and the other set of the double signals consist of signal S₅ being installed at the intersection and a signal (not shown) around the U-tum point on road B.

10. A system for traffic signals and passing traffics at an intersection with five directions roads A, B, C, D and E, comprising: during the first period, passing the traffic on the main road (roads A and B) through the intersection simultaneously; during the second period, allowing the left turn traffics on roads A and B to make a left turn, and allowing both the left turn traffic on road D and the drive straight traffic on road D to make a right turn simultaneously for U-tum on road A, and allowing both the left turn traffic on road C and the drive straight traffic on road C to make a right turn simultaneously for U-turn on road B; and during the third period, passing the traffic on road E (not shown) to drive straight and to make a left rum simultaneously, and allowing the U-tum traffics to keep U-turning on roads A and B, wherein two sets of double signals are installed at a distance of about 70 to about 150 meters on roads A and B for said U-turn traffic to make a U-turn freely and safely, and one set of the double signals consist of signal S₃ being installed at the intersection and signal Si around the U-turn point on road A and the other set of the double signals consist of signal S₅ being installed at the intersection and a signal (not shown) around the U-tum point on road B.