Title:
Traffic intersection
Document Type and Number:
United States Patent 3915580
Abstract:
An improved traffic intersection which permits cars to make left turns onto or from a main highway at grade level without interfering with cars proceeding in either direction on the main highway. The traffic intersection divides a main highway into three parallel segments, with traffic flow alternating on two of the parallel segments in response to signal lights. Left turn traffic is held in storage lanes parallel to the through lanes prior to crossing each of these two parallel segments, with such crossing permitted by signal lights only when that segment is not in use.
Application Number:
05/481689
Publication Date:
10/28/1975
Assignee:
The Raymond Lee Organization Inc. (New York, NY)
International Classes:
E01C1/02; G08G1/00; E01C1/00; E01C1/00
US Patent References:
| 1981361 | Crossing structure | November 1934 | Jones | |
| 2949067 | Traffic intersection | August 1960 | Gedeno | |
| 3399379 | Highway intersection system | August 1968 | Donway | |
Primary Examiner:
Stein, Mervin
Assistant Examiner:
Hawkins, Steven
Attorney, Agent or Firm:
Podell, Howard I.
Claims:
I claim
1. A traffic intersection for providing of grade crossing of divergent flows of traffic without interfering with continuous traffic flow in a given direction, comprising a through road, and a side road meeting the through road, with a road lane of the through road divided into a first and a second set of parallel road lanes at the intersection area, and separated by a third road lane generally parallel to the said first and second road lanes, said first and second sets of parallel road lanes being controlled by traffic signals to permit through traffic to flow alternately through one of the first or second parallel sets of road lanes, with a road lane of the side road crossing the first said parallel road at a first traffic intersection and joining the said third road lane, said third road lane leading from said first traffic intersection to a second traffic intersection at which traffic on the side road meets the said second parallel road lane, with traffic on the side road crossing each of the two traffic intersections controlled by traffic signals so that said crossing traffic is only permitted to cross each of the first and second sets of the road lanes at a time when that set of parallel lane is not utilized by through traffic.
2. The combination as recited in claim 1 in which the side road terminates at the juncture of the second traffic intersection, with the said first and second traffic intersections utilized alternately for traffic turning onto or off the side road.
3. The combination as recited in claim 1 in which the side road continues from the second traffic intersection away from the through road.
Description:
SUMMARY OF THE INVENTION
My invention relates to an improved traffic intersection, and particularly one which prevents cars making a left turn off or onto a main highway from interfering with cars proceeding on the main highway.
The traffic intersection divides a main highway into three parallel segments, with traffic flow alternating on two of the parallel segments in response to signal lights. Left turn traffic is held in storage lanes parallel to the through lanes prior to crossing each of these two parallel segments, with such crossing permitted by signal lights only when that segment is not in use.
BRIEF DESCRIPTION OF THE DRAWINGS
The objects and features of the invention may be understood with reference to the following detailed description of an illustrative embodiment of the invention, taken together with the accompanying drawings in which:
FIG. 1 is a plan view of the traffic intersection, with traffic proceeding in both directions on the main highway or the normal lanes, with left turn traffic being stored between the switch lane and the regular traffic lane;
FIG. 2 is a plan view of the traffic intersection with traffic on the main highway proceeding on a switch lane and similar with left turn traffic crossing the regular lane.
DESCRIPTION OF THE PREFERRED EMBODIMENT
Turning now descriptively to the drawings, in which similar reference characters denote similar elements throughout the several views, FIG. 1 illustrates the traffic intersection 10 in which an East-West highway 20 intersects the terminus of a feeder two-way highway 30 leading to or from the south. Westbound lane 11 of main highway 10 is continuously in operation. Eastbound traffic on lane 12 of main highway 10 alternately employs one of two parallel roadways through the intersection, utilizing either the Regular lane 14 or the switch lane 15 in response to traffic signals 18 and 19 at the entry point to the lanes 14 and 15.
At the start of the cycle, as shown in FIG. 1, southbound traffic from westbound land 11 makes a left turn into feeder lane A which divides from lane 11 and is generally parallel to through lane 11 and switch lane 15. This left turn traffic crosses the switch lane 15, controlled by green signal light 26G and stops at red traffic signal 27R in feeder lane B at the intersection with regular lane 14, on which eastbound traffic is flowing. Feeder lane B is generally parallel to switch lane 15 and regular lane 14. Eastbound switch lane 15 is free of moving traffic since controlling traffic lights 19R and 29R are set to red.
Southbound traffic from eastbound lane 12, and eastbound traffic from northbound lane 31 make normal right turns subject to yield signs without crossing any other traffic.
The second phase of the cycle as shown in FIG. 2 consists of diverting the flow of eastbound traffic from regular lane 14 to switch lane 15 by actuation of green traffic lights 19G and 29G and red traffic lights 18R and 28R.
The left turn traffic previously stored on lane B now crosses idle regular lane 14 in response to green traffic signal 27G and continues either southbound on lane 32 of route 30 or utilizes a feeder road 33 to make a U-turn and to proceed eastbound in that section 14U of lane 14 that is east of the intersection.
During the second phase of the cycle, left turn traffic initiating from lane 11 is stored in lane A halting a red traffic signal 26R at the intersection with the active switch lane 15.
While the intersection 10 has been shown in terms of one through road 20 meeting the terminus of a side road 30, it may be similarly modified to provide for an intersection of two through roads by the addition of more switch lanes. Furthermore, in such a case, a switch lane may be operated in either direction depending on the volume of traffic flow and the time of the day.
Since obvious changes may be made in the specific embodiment of the invention described herein, such modifications being within the spirit and scope of the invention claimed, it is indicated that all matter contained herein is intended as illustrative and not as limiting in scope.